U.S. patent application number 09/790220 was filed with the patent office on 2003-11-06 for method and apparatus for emboli containment.
Invention is credited to Zadno-Azizi, Gholam-Reza.
Application Number | 20030208222 09/790220 |
Document ID | / |
Family ID | 27095869 |
Filed Date | 2003-11-06 |
United States Patent
Application |
20030208222 |
Kind Code |
A1 |
Zadno-Azizi, Gholam-Reza |
November 6, 2003 |
Method and apparatus for emboli containment
Abstract
Disclosed herein is a catheter for use in an emboli containment
system. In one embodiment, the catheter has a tubular body with a
metallic braid construction. Two lumens extend through the tubular
body, the lumen being in a side-by-side configuration. One of the
lumens functions as an inflation lumen, and is in fluid
communication with an inflatable balloon mounted on the distal end
of the catheter. The second lumen is adapted to receive other
therapeutic catheters which comprise the emboli containment system.
In another embodiment, apparatus is provided for treatment of a
stenosis in a lumen in a blood-carrying vessel comprising a main
catheter and a therapeutic catheter. The main catheter comprises a
first flexible elongate tubular member having proximal and distal
extremities. A sealing element is carried on the distal extremity
of the first flexible elongate tubular member. The first flexible
elongate tubular member has a main lumen therein extending from the
proximal extremity to the distal extremity and exits through the
distal extremity. An adapter is mounted on the proximal extremity
of the first flexible elongate tubular member. The therapeutic
catheter comprises a second flexible elongate tubular member having
proximal and distal extremities. An element for performing work is
mounted on the distal extremity of the second flexible elongate
tubular member. An adapter is mounted on the proximal extremity of
the second flexible elongate tubular member. The second flexible
elongate tubular member is slidably mounted in the main lumen of
the first elongate tubular member. A mechanism is carried by the
first flexible elongate tubular member for causing the sealing
element to form an occlusion in the vessel proximal of the stenosis
to provide a working space distal of the sealing element. A
mechanism is coupled to the attachment of the therapeutic catheter
for causing operation of the element for performing work in the
working space adjacent the stenosis.
Inventors: |
Zadno-Azizi, Gholam-Reza;
(Fremont, CA) |
Correspondence
Address: |
KNOBBE MARTENS OLSON & BEAR LLP
2040 MAIN STREET
FOURTEENTH FLOOR
IRVINE
CA
92614
US
|
Family ID: |
27095869 |
Appl. No.: |
09/790220 |
Filed: |
February 21, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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09790220 |
Feb 21, 2001 |
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08813023 |
Mar 6, 1997 |
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6270477 |
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08813023 |
Mar 6, 1997 |
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08650464 |
May 20, 1996 |
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08650464 |
May 20, 1996 |
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08464579 |
Jun 5, 1995 |
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5833650 |
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Current U.S.
Class: |
606/194 ;
606/200 |
Current CPC
Class: |
A61M 25/0075 20130101;
A61M 2025/0018 20130101; A61M 25/0029 20130101; A61M 2025/0034
20130101; A61M 2025/0081 20130101; A61M 2025/1093 20130101; A61M
25/104 20130101; A61M 2025/1031 20130101; A61B 17/12045 20130101;
A61M 25/1018 20130101; A61B 2017/22055 20130101; A61M 25/0012
20130101; A61M 25/1027 20130101; A61B 2017/22067 20130101; A61B
17/12136 20130101; A61M 2025/0036 20130101; A61M 25/0068 20130101;
A61M 2025/0681 20130101; A61M 25/007 20130101; A61M 25/0054
20130101; A61B 2017/12127 20130101; A61M 2025/1079 20130101; A61B
17/12172 20130101; A61M 2025/1015 20130101; A61M 25/0053 20130101;
A61M 2025/0037 20130101; A61M 25/0026 20130101; A61M 25/10
20130101; B29C 55/04 20130101; A61M 2025/1045 20130101; A61B
17/12109 20130101; A61B 17/22 20130101; A61B 2017/320716 20130101;
A61M 25/0032 20130101; A61M 2025/1052 20130101; A61M 2025/0183
20130101; A61M 25/0009 20130101; A61M 2025/109 20130101; A61B
2017/22084 20130101; A61B 2217/005 20130101; A61M 25/1011
20130101 |
Class at
Publication: |
606/194 ;
606/200 |
International
Class: |
A61M 029/00 |
Claims
What is claimed is:
1. A method of protecting a patient from embolization during a
percutaneous procedure on a vessel, comprising the steps of:
providing a guidewire having proximal and distal ends, a proximal
and a distal region, an expandable filter associated with the
distal region, and a removable sheath which covers the expandable
filter and is slidable over the guidewire; introducing the distal
end of the guidewire into the patient's vessel with the sheath
covering the expandable filter, and positioning the filter
downstream of a region of interest, wherein the sheath and
guidewire cross the region of interest; sliding the sheath toward
the proximal end of the guidewire and removing the sheath from the
vessel, wherein the expandable filter is uncovered; deploying the
filter; advancing over the guidewire a stent-deployment catheter to
the region of interest; and expanding the stent at the region of
interest, wherein embolic material is generated and captured before
the expandable filter is removed from the patient's vessel.
2. The method of claim 1, further comprising the steps of: removing
the stent & deployment catheter from the vessel; advancing the
sheath into the vessel over the guidewire until the sheath covers
the expandable filter; and removing the guidewire and sheath from
the vessel.
3. The method of claim 1, wherein the stent is deployed by
inflation of a balloon.
4. The method of claim 1, wherein the stent-deployment catheter is
a rapid exchange catheter.
5. The method of claim 1, wherein the expandable filter comprises a
plurality of struts, each strut having a proximal end in contact
with the guidewire and a distal end in contact with the guidewire,
and wherein the struts expand to the shape of an eggbeater.
6. The method of claim 1, wherein the expandable filter includes a
filter mesh.
7. The method of claim 1, wherein the expandable filter comprises a
plurality of radially biased struts.
8. The method of claim 1, wherein the expandable filter comprises a
plurality of radially expandable struts which are operable to
expand radially outwardly.
9. A percutaneous system having filter and stent deployment
capabilities, comprising: a guidewire having proximal and distal
ends, a proximal and distal region, and an expandable filter
associated with the distal region; a sheath which is shaped to
receive the guidewire and retain the filter in a contracted
condition, and to slidably release the filter to an expanded
condition when the sheath moves toward the proximal end of the
guide wire; a catheter having a proximal and a distal end, a
proximal and a distal region, and a lumen which slidably receives
the guidewire; and an expandable stent disposed about the distal
region of the catheter, the stent having a first diameter which
permits intraluminal delivery of the stent into a body passageway
and which places the stent in close proximity to the catheter, and
having a second expanded diameter adapted to substantially engage a
wall of the body passageway, wherein, during use, the guidewire is
positioned across a region of interest, the filter is expanded, and
the stent is deployed within the region of interest and remains in
place after removal of the catheter from the vessel.
10. The system of claim 9 wherein the expandable filter comprises
an expansion frame and a filter mesh attached to the expansion
frame.
11. The system of claim 10, wherein the expansion frame comprises a
plurality of struts which, upon activation, bend outwardly to the
enlarged condition.
12. The system of claim 11, wherein the guidewire includes a distal
segment which can be moved longitudinally relative to a proximal
segment, and wherein the proximal end of each strut is in contact
with the proximal segment and a distal end of each strut is in
contact with the distal segment, and wherein the struts expand
radially when the distal segment is pulled toward the proximal
region of the catheter.
13. The system of claim 10, wherein the expansion frame comprises
radially biased struts attached to an outer surface of the
catheter.
14. The system of claim 13, wherein a proximal end of each strut is
in contact with the catheter and the distal end of each strut is in
contact with the catheter, and wherein the struts expand to the
shape of an eggbeater.
15. The system of claim 10, wherein the expansion frame comprises
an inflation seal.
16. The system of claim 15, further comprising an inflation system
comprising a first lumen adapted to receive pressurized fluid and a
second lumen adapted to evacuate gas, and wherein the inflation
seal further includes an entry port in fluid communication with the
first lumen of the inflation system and an exit port in fluid
communication with the second lumen of the inflation system, so
that when fluid is advanced through the first lumen, the fluid
enters the inflation seal and forces gas from the inflation seal
through the second lumen, thereby purging the system of gas.
17. The system of claim 15, wherein the inflation seal comprises a
tubular balloon which encloses a chamber and wherein the entry port
and exit port are in close proximity, and wherein a septum is
disposed between the entry and exit ports.
18. The system of claim 9, wherein the stent and the filter are
self-expanding.
19. The system of claim 9, wherein the stent is removable.
20. The system of claim 9, wherein the stent is self-expanding.
21. The system of claim 9, wherein the stent comprises stainless
steel material.
22. The system of claim 9, wherein the stent comprises nitinol
material.
23. The system of claim 9, wherein the stent has a shape selected
from the group consisting of a tube, a sheet, a wire, a mesh, and a
spring.
24. The system of claim 9, wherein the sheath is shaped to receive
the catheter and retain the stent at the first diameter.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of application Ser. No.
08/813,023, filed on Mar. 6, 1997, which is a continuation-in-part
of application Ser. No. 08/650,464 filed on May 20, 1996, the
entirety of which is incorporated herein by reference, which is a
continuation-in-part of application Ser. No. 08/464,579, filed Jun.
5, 1995, now U.S. Pat. No. 5,833,650.
BACKGROUND OF THE INVENTION
[0002] The present invention generally relates to medical devices,
and in particular, to catheters which can be used in an emboli
containment system. This invention also relates to an apparatus and
method for treating occluded vessels in living bodies and more
particularly balloon catheters and balloon guide wires for treating
occlusions in vessels in human bodies, as for example carotid
arteries.
[0003] Balloon angioplasty, and other transluminal medical
treatments, are well-known, and have been proven efficacious in the
treatment of stenotic lesions in blood vessels. The application of
such medical procedures to certain blood vessels, however, has been
limited, due to the risks associated with creation of emboli during
the procedure. For example, angioplasty is not the currently
preferred treatment for lesions in the carotid artery, because of
the possibility of dislodging plaque from the lesion, which can
enter the various arterial vessels of the brain and cause permanent
brain damage. Instead, surgical procedures are currently used, but
these procedures present substantial risks.
[0004] One solution to this problem is the use of a multi-catheter
emboli containment system, as disclosed in the above-referenced
application Ser. No. 08/650,464. As disclosed therein, a treatment
chamber within a blood vessel is formed by two occlusion balloons
on opposite sides of a stenotic lesion, thereby preventing emboli
migration during the treatment procedure. The chamber is created by
two occlusion balloon catheters which are slidably disposed with
respect to one another.
[0005] Emboli containment procedures of this type are advantageous,
because they permit the clinician to utilize the benefits of
transluminal treatment in a wider variety of blood vessels.
However, the procedures require the complex coordination of
multiple catheters. Consequently, it is desirable to have catheters
which make it easier for the clinician to utilize an emboli
containment system. It is also desirable that the catheters used in
the emboli containment system have a high degree of flexibility, to
navigate tortuous blood vessel networks.
[0006] Consequently, there exists a need for improved emboli
containment catheters. This is especially true in the context of
the "main" catheter, through which other catheters are inserted and
controlled to form the emboli containment system. There is also a
need for new and improved apparatus and methods which make it
possible to treat occluded vessels without endangering the
patient.
SUMMARY OF THE INVENTION
[0007] The present invention advantageously provides as a main
catheter an occlusive device adapted for use in a multi-catheter
emboli containment system. In one aspect of the present invention,
there is provided a catheter, comprising an elongate flexible
tubular body having a proximal end and a distal end. The tubular
body incorporates a metallic member, which may comprise a braid or
a coil. A main lumen and an inflation lumen extend through the
tubular body, and are in a side-by-side configuration. The main
lumen is sized to receive a therapeutic and/or diagnostic device
such as a balloon angioplasty catheter or an atherectomy catheter.
The tubular body is provided with a manifold. The manifold has an
aspiration port which is in fluid communication with the main
lumen. The distal end of the tubular body also has a tip formed of
a more flexible material than that used to form the tubular
body.
[0008] In one preferred embodiment, an inflatable balloon is
mounted on the distal end of the tubular body. An inflation port is
also provided on the manifold in this embodiment. The inflation
port is in fluid communication with the inflation lumen. In this
embodiment, the inflatable balloon is formed of a block copolymer
of styrene-ethylene-butylenestyrene.
[0009] In another preferred embodiment, the metallic braid or coil
is formed of a metal selected from the group consisting of 304,
316, or 400 series stainless steel, nitinol, platinum, gold,
Elgiloy.TM., or combinations thereof. Where a metallic braid is
used, it may optionally have a braid density at a first point on
the tubular body that is greater than the braid density of the
metallic braid at a second point on the tubular body by at least 20
picks per inch. Similarly, where a metallic coil is used, it may
optionally have a coil density at a first point on the tubular body
that is greater than the coil density at a second point on the
tubular body.
[0010] In another aspect of the present invention, there is
provided a catheter comprising an elongate flexible tubular body
having a proximal end and a distal end. Alternatively, there may be
provided a circular cross-sectional configuration at the proximal
end which is continuous with a distal end having a reduced internal
and outer tubular body diameters. A first and second lumen extend
through the tubular body from the proximal end to the distal end in
a side-by-side configuration. The first lumen has a generally
circular cross-sectional configuration at the proximal end and a
generally oval cross-sectional configuration at the distal end. The
second lumen has a diameter no smaller than 0.05 inches, preferably
no smaller than 0.08 inches, and is adapted to slidably accommodate
a therapeutic or diagnostic device.
[0011] In one preferred embodiment, an inflatable balloon is
mounted on the distal end of the tubular body. The inflatable
balloon is in fluid communication with the first lumen, such that
fluid passing through the first lumen may be used to inflate or
deflate the inflatable balloon. The second lumen size may vary in
certain embodiments, such that in one embodiment, the second lumen
has a diameter no smaller than about 0.05 inches, and is preferably
no less than 0.080 inches.
[0012] In another aspect of the present invention, there is
provided a catheter with variable stiffness, comprising a tubular
body having a proximal end and a distal end. A metallic braid or
metallic coil is within the tubular body. In one embodiment, the
proximal end of the tubular body has a lower braid or coil density
than the distal end. In another embodiment, the braid or coil
density is kept constant along the length of the tubular body, and
the tubular body is formed of materials with greater stiffness at
the proximal end. In another embodiment, a combination of braids
and coils of varying density can be used at various points along
the tubular body, to create a catheter tubular body having a more
flexible distal end.
[0013] In another aspect of the present invention, there is
provided a method of making a catheter tubular body. The method
comprises providing a first polymeric tube formed of a first
material having a first melting point. The first polymeric tube is
then inserted into a second polymeric tube to form a combined tube.
The second polymeric tube is formed of a second material having a
second melting point which is less than the first melting point.
The combined tube is then placed adjacent to a third tube. The
third tube is formed in part of the second material. The tubes are
then heated to a temperature greater than the second melting point
but less than the first melting point, such that the combined tube
melt fuses with third tube to form a catheter tubular body having
two lumen extending therethrough in a side-by-side configuration.
The first material may be selected from the group comprising
polyimide, polyamide, PET and PEEK, blends thereof and the second
material may be selected from the group comprising Pebax.TM.,
polyethylene, nylon, or Hytrel.TM. or blends thereof. Preferably,
the temperature of the heating step is from about 250.degree. to
600.degree. F. It is also preferred that the third tube incorporate
a metallic member, such as a braid or coil.
[0014] In general, it is an objection of the present invention to
provide an apparatus or an assembly and method which can be used
with approved diagnostic and therapeutic devices while minimizing
the opportunities for emboli to migrate downstream.
[0015] Another object of the present invention to provide an
apparatus or assembly and method of the above character which makes
it possible to perform therapeutic procedures without using
perfusion.
[0016] Another object of the invention is to provide an apparatus
or assembly and method of the above character in which the proximal
balloon utilized is a balloon carried by a guide wire.
[0017] Another object of the invention is to provide an apparatus
or assembly and method of the above characters in which the
inflation fitting carried by the proximal extremity of the
balloon-on-a-wire is removable so that catheters can be slid over
the wire without removal of the wire from the site in which it is
disposed.
[0018] Another object of the present invention is to provide an
apparatus or assembly and method for treating occluded vessels of
the above character which makes it possible to prevent downstream
flow of debris or emboli.
[0019] Another object of the invention is to provide an apparatus
and method which makes it possible to reverse the flow of blood in
an occluded vessel during the time that a stenosis is being
crossed.
[0020] Another object of the invention is to provide an apparatus
and method of the above character in which a negative pressure is
created within the vessel to reverse the flow of blood in the
vessel.
[0021] Another object of the invention is to provide an apparatus
and method of the above character in which it is only necessary to
stop the flow of blood in a vessel of a patient for a very short
period of time.
[0022] Another object of the invention is to provide an apparatus
and method in which a working space is provided in the vessel free
of blood for treatment of the stenosis.
[0023] Another object of the invention is to provide an apparatus
and method of the above character in which material which is
dislodged during the treatment of the occlusion or stenosis is
removed by suction.
[0024] Another object of the invention is to provide an apparatus
and method of the above character in which blood is shunted around
the working space.
[0025] Another object of the invention is to provide an apparatus
and method in which a cutting device is utilized for treatment of
the stenosis or atheroma in the vessel and in which the material
removed from the stenosis or atheroma is aspirated out of the
operating space.
[0026] Another object of the invention is to provide an apparatus
and method of the above character in which the amount of material
removed from the stenosis or atheroma can be precisely
controlled.
[0027] Another object of the invention is to provide an apparatus
and method of the above character which makes it possible to treat
stenoses or occlusion in the vessel which are normally not
accessible for surgical procedures.
[0028] Another object of the invention is to provide an apparatus
and method of the above character which utilizes two spaced apart
balloons to create the working space in the vessel.
[0029] Another object of the invention is to provide an apparatus
and method of the above character that can be utilized to create a
working space in a vessel having a bifurcation therein and in which
the working space includes the bifurcation.
[0030] Another object of the invention is to provide an apparatus
and method of the above character which utilizes three spaced apart
balloons to create the working space in the vessel having a
bifurcation therein.
[0031] Another object of the invention is to provide an apparatus
and method of the above character which includes a control console
for controlling the inflation of the blood flow pump.
[0032] Another object of the invention is to provide an apparatus
and method of the above character which is particularly adapted for
use with the carotid vessels.
BRIEF DESCRIPTION OF THE DRAWINGS
[0033] FIG. 1 is a side view of an embodiment of the catheter of
the present invention.
[0034] FIG. 2 is a cross-sectional view of catheter of FIG. 1 along
lines 2-2.
[0035] FIG. 3 is a cross-sectional view of the catheter of FIG. 1
along lines 3-3.
[0036] FIG. 4 is a longitudinal cross-sectional view of the distal
end of the catheter of FIG. 1.
[0037] FIG. 5 is an enlargement of the region circumscribed by
lines 5-5 of the catheter of FIG. 4.
[0038] FIG. 6 is an illustration of the catheter of the present
invention as used in an emboli containment system.
[0039] FIG. 7 is a cross-sectional view of the emboli containment
system of FIG. 6 along lines 7-7.
[0040] FIG. 8 is a cross-sectional view of the emboli containment
system of FIG. 6 along lines 8-8.
[0041] FIG. 9 is a cross-sectional view of the emboli containment
system of FIG. 6 along lines 9-9.
[0042] FIGS. 10A-E illustrate the use of an embodiment of the
catheter of the present invention in an emboli containment
treatment procedure.
[0043] FIG. 11 is a side-elevational view partially in section
showing the catheter apparatus or assembly of the present invention
for treating occluded vessels.
[0044] FIG. 12 is a cross-sectional view taken along the line 12-12
of FIG. 11.
[0045] FIG. 13 is a cross-sectional view taken along the line 13-13
of FIG. 11.
[0046] FIG. 14 is a cross-sectional view taken along the line 14-14
of FIG. 11.
[0047] FIG. 15 is a schematic illustration of how the catheter
apparatus shown in FIG. 11 is deployed in a carotid artery.
[0048] FIGS. 16A-16E are illustrations showing the various steps
utilized in deployment of the catheter apparatus in performing the
method of the present invention in a vessel where a bifurcation is
not present.
[0049] FIG. 17 is a side-elevational view partially in section of
another embodiment of a catheter apparatus or assembly
incorporating the present invention for treating occluded vessels
using an atherectomy device.
[0050] FIG. 18 is a cross-sectional view taken along the line 18-18
of FIG. 17.
[0051] FIG. 19 is a cross-sectional view taken along the line 19-19
of FIG. 17.
[0052] FIG. 20 is a side-elevational view in section of the distal
extremity of another embodiment of a catheter apparatus
incorporating the present invention and utilized for delivering an
expandable stent to a stenosis.
[0053] FIG. 21A is a schematic illustration showing the manner in
which the apparatus of the present invention is utilized in
connection with vessels of a patient in performing the method of
the present invention.
[0054] FIG. 21B is an additional partial schematic illustration
showing interconnections in the catheter apparatus shown in FIG.
21A.
[0055] FIG. 22 is a plan view of another embodiment of a catheter
apparatus incorporating the present invention.
[0056] FIG. 23 is a cross-sectional view taken along the line 23-23
of FIG. 22.
[0057] FIG. 24 is an end elevational view looking down the line
24-24 of FIG. 22.
[0058] FIGS. 25A, B, C, and D are illustrations or cartoons showing
the method of the present invention being utilized with the
apparatus shown in FIG. 21 in a vessel having a bifurcation
therein.
[0059] FIG. 26 is a side-elevational view of a main catheter
incorporating the present invention.
[0060] FIGS. 26A and 26B are partial side-elevational views of the
distal extremities showing alternative embodiments of the main
catheter of the present invention incorporating, respectively,
Judkins left shape and Judkins right shape in their distal
extremities.
[0061] FIG. 27 is a cross-sectional view taken along the line 27-27
of FIG. 26.
[0062] FIG. 28 is a cross-sectional view taken along the line 28-28
of FIG. 26.
[0063] FIG. 29 is an enlarged partial cross-sectional view of the
distal extremity of the catheter shown in FIG. 26.
[0064] FIG. 30 is a side-elevational view of the balloon-on-a-wire
construction incorporating the present invention.
[0065] FIG. 31 is a cross-sectional view taken along the line 31-31
of FIG. 30.
[0066] FIG. 32 is an enlarged cross-sectional view of the distal
extremity of the construction in FIG. 30.
[0067] FIG. 33 is a cross-sectional view similar to FIG. 32 but
showing a different embodiment utilizing a twisted dual core.
[0068] FIG. 34 is a cross-sectional view similar to FIG. 32 but
showing the use of a twisted core.
[0069] FIG. 35 is a cross-sectional view of the proximal removable
fitting of the construction shown in FIG. 30.
[0070] FIG. 36 is a side-elevational view partially in cross
section of an irrigation catheter incorporation the present
invention.
[0071] FIGS. 36A and 36B are side-elevational views of the distal
extremities of additional embodiments of irrigation catheters
incorporating the present invention.
[0072] FIGS. 37-43 are cartoons showing the manner in which the
apparatus of the present invention shown in FIGS. 26-36 is used
performing a therapeutic procedure in accordance with the present
invention.
[0073] FIG. 44 is a side-elevational view partially in
cross-section of another embodiment of a main catheter
incorporating the present invention.
[0074] FIG. 45 is a side-elevational view partially in
cross-section showing another embodiment of an irrigation catheter
incorporating the present invention.
[0075] FIGS. 46-50 are cartoons showing the manner in which a
therapeutic carotid procedure is performed in accordance with the
present invention where there is a bifurcation.
[0076] FIG. 51 is a side-elevational view partially in section of
another embodiment of a balloon-on-a-wire incorporating the present
invention.
[0077] FIG. 52 is a cross-sectional view taken along the line 52-52
of FIG. 51.
[0078] FIG. 53 is a side-elevational view in section of another
embodiment of a catheter apparatus incorporating the present
invention for treating occluded vessels.
[0079] FIG. 54 is a side-elevational view in section similar to
FIG. 53 but showing the apparatus in FIG. 53 with the
self-expandable sealing means deployed.
[0080] FIG. 55 is a side-elevational view in section of another
embodiment of a catheter apparatus incorporating the present
invention for treating occluded vessels.
[0081] FIG. 56 is a view similar to FIG. 55 but showing the
self-expandable sealing means deployed.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0082] Referring to FIG. 1, there is depicted an embodiment of the
balloon catheter of the present invention. Although illustrated and
described below in the context of an emboli containment system
featuring balloon dilatation treatment of a stenotic lesion, it is
to be understood that the present invention can be easily adapted
to a variety of emboli containment treatment applications. For
example, the present inventors contemplate that the catheter of the
present invention can be used in emboli containment treatment
procedures which include atherectomy, stent implantation, drug
delivery, as well as other applications. Furthermore, although
depicted and described as a two lumen catheter, it should be
appreciated that the present invention may also be adapted to
catheters having more than two lumen. The manner of adapting the
present invention to these various treatments and structures will
become readily apparent to those of skill in the art in view of the
description which follows.
[0083] Catheter 10 generally comprises an elongate flexible tubular
body 16 extending between a proximal control end 12 and a distal
functional end 14. Tubular body 16 has a main lumen 30 which
extends between ends 12 and 14. Main lumen 30 terminates in a
proximal opening 23 and a distal opening 27. A smaller inflation
lumen 32, configured in a side-by-side relationship with main lumen
30, extends along the length of tubular body 16 and may terminate
within or near an occlusion balloon 26 mounted on the distal end 14
of catheter 10, as described below. Inflation lumen 32 is in fluid
communication with balloon 26, such that fluid passing through
inflation lumen 32 may be used to inflate or deflate balloon 26. In
some embodiments, the inflation lumen may originate at a point
distal to the proximal end 12, and extend distally from that point
in a side-by-side configuration with main lumen 30.
[0084] In some embodiments, instead of an occlusion balloon 26,
distal end 14 is provided with a mechanical occlusive device such
as a pull-wire activated braid which filters all particles larger
than 12 microns. Alternatively, other occlusive filtering devices
may also be used, as is known by those of skill in the art.
[0085] A control manifold 19 is provided at the proximal end 12 of
catheter 10. Control manifold 19 is generally provided with a
number of ports to provide access to the catheter lumen. For
example, for the embodiment depicted in FIG. 1, control manifold 19
is provided with a catheter end-access port 22 and a catheter
side-access port 24, to provide an introduction point for the
insertion of other catheters into lumen 30. Ports 22 and 24 are
preferably provided with standard Touhy Borst connectors, although
other sealing type connectors, such as a hemostasis valve, may be
used. Manifold 19 is also provided with an aspiration port 20 which
is in fluid communication with lumen 30, for attachment of devices
to aspirate fluid into opening 27, through lumen 30, and out port
20. An inflation port 18, in fluid communication with lumen 32, is
further provided on manifold 18 for attachment of devices to
inflate or deflate balloon 26. In one preferred embodiment, ports
18 and 20 are provided with standard luer connectors, to facilitate
attachment of standard inflation or aspiration apparatus,
respectively, to ports 18 and 20. Other embodiments of catheter 10
may feature more or less ports, depending upon the number of lumen
in the catheter and the desired functionalities of the
catheter.
[0086] Manifold 19 is preferably formed out of hard polymers or
metals, which possess the requisite structural integrity to provide
a functional access port to the catheter lumen, such as for balloon
inflation or fluid aspiration. In one preferred embodiment,
manifold 19 is integrally formed out of medical grade
polycarbonate. Other suitable materials may be used to form
manifold 19, such as polyvinyl chloride, acrylics, acrylonitrile
butadiene styrene (ABS), nylon, and the like.
[0087] Manifold 19 is attached to tubular body 16 so that the
various ports are placed in communication with the appropriate
lumen, as described above in connection with FIG. 1. Preferably, a
strain relieving connector 11 is used to join manifold 19 to
tubular body 16. For the embodiment depicted in FIG. 1, strain
relieving connector 11 consists of a length of flexible polymeric
tubing, such as 40 durometer (D) Pebax.TM., or other polyether
block amides, and other similar materials. Tubular body 16 is
inserted in one end of strain relieving connector 11, and the other
end of strain relieving connector 11 is inserted into manifold 19.
Suitable adhesives, such as a cyanoacrylate, epoxies, or uv curable
adhesives, may be used to bond manifold 19 to strain relieving
connector 11. Alternately, manifold 19 may also be insert molded
with the tubular body 16, as is known by those of skill in the art.
Adhesives may also be used to bond the strain relieving connector
11 to tubular body 16, or alternately, conventional heat bonding,
as known to those of skill in the art, may be used to attach
tubular body 16 to strain relieving connector 11.
[0088] The length of tubular body 16 may be varied considerably
depending upon the desired application. For example, where catheter
10 is to be used as part of an emboli containment system for
treatment of carotid artery disease, with catheter 10 being
introduced at the groin, the length of tubular body 16 may range
from 80 to 110 centimeters, and is preferably 95 cm. Other
treatment procedures, requiring a longer or shorter tubular body
16, are easily accommodated by the present invention, by forming a
tubular body 16 of the desired length during the manufacturing
process.
[0089] The outer diameter of tubular body 16 may also be varied
considerably, and in most cases, will depend upon the intended
treatment procedure for which catheter 10 will be used. That is,
the outer diameter of tubular body 16 must be large enough to be
capable of forming a main lumen 30 which can slidably accommodate
the other catheters used in the emboli containment system, as
described in detail below. However, the outer diameter of tubular
body 16 must also be smaller than the internal diameter of smallest
blood vessel through which catheter 10 passes during the selected
treatment procedure. In general, the diameter of main lumen 30 may
range from at least about 0.05 inches to about 0.12 inches, and be
capable of accommodating many types of catheters to be used
therein, while still maintaining a low profile for the diameter of
tubular body 16.
[0090] For many treatment applications, it has been found that a
tubular body having an outside diameter of no more than about 0.135
inches (10 French) is preferred. Advantageously, with an outer
diameter of this size, main lumen 30 may have an internal diameter
of about 0.10 inches, making lumen 30 capable of accommodating a
wide variety of treatment catheters, or catheters used for
diagnostic purposes. Of course, as will be appreciated by those of
skill in the art, where the catheters intended to be inserted into
lumen 30 are known to have outer diameters significantly smaller
than 0.10 inches, such that lumen 30 may be smaller than 0.10
inches and still accommodate them, a tubular body 16 having an
outer diameter of less than 0.135 inches may be selected.
[0091] Although not required, the interior surface of lumen 30 may
be provided with a liner 35 formed of a lubricous material, to
reduce the frictional forces between the lumen surface and the
catheters which are inserted into lumen 30. In one preferred
embodiment, liner 35 is formed out of polytetrafluoroethylene
(PTFE). Lubricous materials other than PTFE, which are
biocompatible, fairly flexible, and easily mounted to other
polymeric materials of the type used to form catheter tubular
bodies, may also be used to form liner 35. Examples of such
materials include polyethylene, Pebax.TM., nylon, and the like.
Where increased flexibility of the distal end 14 of catheter 10 is
desired, Pebax.TM. may be used in place of PTFE along a selected
portion of distal end 14, such as the distal most 15-20 cm of end
14.
[0092] To minimize the outer diameter of tubular body 16, it is
preferable that inflation lumen 32 be as small as possible in
accordance with its function. That is, inflation lumen 32 is
preferably no larger than required to provide sufficient fluid to
balloon 26 for rapid inflation, or so that fluid may be quickly
withdrawn from balloon 26 during deflation. For compliant expansion
balloons of the type described below, inflation lumen diameters of
from about 0.008 inches to about 0.018 inches are satisfactory,
with a diameter of about 0.014 inches being preferred for some
applications.
[0093] Furthermore, in one embodiment, as illustrated in FIGS. 1-3,
the outer diameter of tubular body 16 just proximal to balloon 26
is minimized by providing an inflation lumen 32a with an oval
cross-sectional configuration, as illustrated in FIG. 3.
Preferably, inflation lumen 32a has an oval cross-sectional
configuration which extends proximally from the proximal edge
balloon 26 by a distance of at least 0.1 cm, more preferably 1 cm,
and optimally by a distance equal to the length of tubular body 16.
For ease of manufacturing, the cross-sectional configuration of
lumen 32 at points further proximal to balloon 26 may be generally
circular, as illustrated in FIG. 2. Where the lumen configuration
differs from proximal to distal end, as illustrated in FIGS. 2 and
3, a region of transition 33 is provided wherein the lumen
configuration changes from circular to oval.
[0094] It will be appreciated by those of skill in the art that
other cross-sectional configurations of lumen 32a may be provided
and still function to reduce the profile of tubular body 16. For
example, triangular, rectangular, or other non-oval cross sectional
configurations are easily adapted to lumen 32a, and the manner of
incorporating such alternative cross-sectional configurations will
be readily apparent to those of skill in the art in view of the
description which follows.
[0095] A variety of different manufacturing methods may be used to
alter the cross-sectional configuration of lumen 32, as will be
appreciated by those of skill in the art. In one preferred method,
lumen 32 is formed of a polymeric tube, such as a polyimide tube,
which has been compressed at one end so that it has the desired
oval shape. The polyimide tube is then inserted into a second tube
formed of a material having a lower melting point than polyimide,
such as 72D Pebax.TM.. The combination is then heat bonded to
another tube defining main lumen 30, such as a braided Pebax.TM.
tube, as described below. The heat bonding takes place at a
temperature greater than the melting temperature of Pebax.TM., but
less than the melting temperature of polyimide, so that the
Pebax.TM. tubes melt fuse to form the two lumen tubular body.
[0096] Alternately, the cross-sectional configuration, as well as
the cross-sectional area of lumen 32, may also be altered by
joining two separate polymeric tubes together to form a continuous
inflation lumen 32. One of the tubes, corresponding to the proximal
end of catheter 10 as shown in FIG. 3, may have a circular
cross-sectional configuration. The second tube, corresponding to
the distal end of catheter 10 as shown in FIG. 2, has an oval
configuration. One end of a mandrel may be inserted into each of
the tubes, and conventional heat bonding may be used to create the
cross-sectional configuration transition. As before, the combined
tube may then be heat bonded to a second tube defining main lumen
30 to form tubular body 16.
[0097] As illustrated in FIG. 1, an inflatable balloon 26 is
mounted on the distal end 14 of catheter 10. In most applications
where catheter 10 is to be used in an emboli containment treatment
procedure, inflatable balloon 26 will function as an occlusion
balloon, to prevent blood from passing through the blood vessel
distal of balloon 26. Thus, inflatable balloon 26 is preferably
able to expand to fit a variety of different blood vessel
diameters. Accordingly, it is preferred that inflatable balloon 26
have a compliant expansion profile, tending to increase in radial
diameter with increasing inflation pressure. To achieve this,
balloon 26 may be made out of materials which impart such expansion
characteristics, including elastomeric materials such as latex or
silicone. In one preferred embodiment, inflatable balloon 26 is
formed out of a material comprising a block copolymer of
styrene-ethylene-butyle- ne-styrene, sold under the trade name
C-Flex.TM.. Further details as to balloons of this type are
disclosed in our copending application entitled PRE-STRETCHED
CATHETER BALLOON, Ser. No. 08/812,139, filed Mar. 6, 1997, now
abandoned, the entirety of which is incorporated by reference.
[0098] Inflatable balloon 26 may be placed in fluid communication
with lumen 32a via a fill hole (not shown) extending through
tubular body 16 within balloon 26, such that fluid may be
introduced into lumen 32 through inflation port 18 to inflate
balloon 26. Alternately, lumen 32a may terminate within balloon 26,
to provide the requisite fluid communication. Balloon 26 may be
attached to tubular body 16 by any suitable manner known to those
of skill in the art, such as adhesives or heat bonding.
[0099] Tubular body 16 must have sufficient structural integrity,
or "stiffness," to permit catheter 10 to be advanced through
vasculature to distal arterial locations without buckling or
undesirable bending of tubular body 16. However, it is also
desirable for tubular body 16 to be fairly flexible near distal end
14, so that tubular body 16 may be navigated through tortuous blood
vessel networks. Thus, in one preferred embodiment, tubular body 16
is made to have variable stiffness along its length, with the
proximal portion of tubular body 16 being less flexible than the
distal portion of tubular body 16. Advantageously, a tubular body
16 of this construction enables a clinician to more easily insert
tubular body 16 into blood vessel networks difficult to reach by a
tubular bodies having uniform stiffness. This is because the
stiffer proximal portion provides the requisite structural
integrity needed to advance tubular body 16 without buckling, while
the more flexible distal region is more easily advanced into and
through tortuous blood vessel passageways.
[0100] In one preferred embodiment, variable stiffness along the
length of tubular body 16 is achieved by forming a polymeric
tubular body 16 which incorporates along its length a variable
stiffness metallic member. The metallic member may comprise a braid
or coil, and may have varying braid density or coil pitch at
different points along the catheter tubular body. For example, as
shown in FIGS. 2 and 3, tubular body 16 may be provided with a
braid 36 incorporated into the wall structure of tubular body 16.
Referring to FIG. 1, to achieve variable stiffness, proximal region
A of catheter 10 is provided with a metallic braid 36 having a
lower braid density than that present in the metallic braid 36a of
distal region B. The lower braid density of proximal region A
permits polymer flow in between the braids during the formation of
the tubular body. Because the polymer is relatively stiffer than
the braid, the lower braid density results in proximal region A
being less flexible, or "stiffer", than distal region B. In one
preferred embodiment, the braid density of proximal region A varies
from 60 to 80 picks per inch, while that of region B varies from 90
to 110 picks per inch.
[0101] As will be appreciated by those of skill in the art,
metallic members other than braids may be incorporated into tubular
body 16 to create variable stiffness. For example, a metallic coil
may be introduced into tubular body 16. The coil may have different
pitch along the length of tubular body 16, such that region A is
provided with a coil having a lower pitch than that present in
region B. The manner of adapting a coil, and other metallic
members, to the catheter tubular body in place of a braid will
become readily apparent to those of skill in the art in view of the
description which follows.
[0102] The precise density of the braiding provided to regions A
and B can be varied considerably at the point of manufacture, such
that catheters having a variety of different flexibility profiles
may be created. Moreover, the braid density may be varied within
catheter regions A and B as well, by providing a metallic braid
which has a braid density gradient along its length. For example,
the most proximal part of region A may be provided with a metallic
braid 36 having a braid density of about 60 picks per inch, with
the braid density increasing distally at a certain rate so that the
final pick count is not more than 110 picks per inch at the distal
end.
[0103] A variety of different metals, known to be ductile and
shapeable into fine wires and flat ribbons, having a diameter of
about 0.0005 inches to about 0.005 inches for wires, or the same
thickness for a ribbon, may be used to form the metallic braids 36
and 36a or metallic coils. For example, stainless steel, platinum,
gold and nitinol, or combinations thereof are all suitable metals.
In one preferred embodiment, braid 36 is formed of stainless steel,
and has a braid density which varies from 70 picks per inch at the
most proximal part of region A, to 100 picks per inch at the most
distal part of region B.
[0104] Metallic braids 36 may be introduced into the structure of
tubular body 16 through conventional catheter forming techniques.
For example, tubular body 16 may be formed by braiding over a 72D
Pebax.TM. tube that has a removable core mandrel in the internal
diameter supporting the Pebax.TM. tube, and then inserting the
braided tube into a 72D Pebax.TM. outer tube at the proximal region
A and a 35D Pebax.TM. tube at the distal region B, so that the
braid is sandwiched between the inner and outer tubes. A stainless
steel support mandrel may be inserted into the removable core
mandrel as additional support. A shaping container such as a
fluorinated ethylene propylene (FEP) shrink tube is inserted over
the outer Pebax.TM. tube, and the entire apparatus may then be
placed in a hot box or oven kept at a temperature slightly greater
than the melting temperature of the Pebax.TM. tubes. The Pebax.TM.
tubes will melt and fuse together, and once cooled, will form a
tubular body incorporating the metallic braid. The shaping
container and mandrels may then be removed and discarded.
[0105] In another embodiment, variable stiffness of tubular body 16
may be achieved by forming regions A and B of tubular body 16 out
of polymeric materials having differing degrees of stiffness. For
example, one half of an inner tube of 72D Pebax.TM. may be inserted
into an outer tube of 35D Pebax.TM., and the other half of the
inner tube may be inserted into a 72D Pebax.TM. outer tube. The
combination may then be heat fused, as described above. The 35D/72D
Pebax.TM. combination forms a more flexible tubular body than the
region 72D/72D Pebax combination. More or less flexible materials
may be used as desired to alter the flexibility of the resulting
tubular body. Furthermore, the flexibility of the various regions
of a tubular body formed in this manner may be varied further by
incorporating a metallic member having either a uniform density, or
a varying density, into the tubular body, as described above.
[0106] In another preferred embodiment, variable stiffness along
the length of the tubular body may be achieved by using different
metallic members in regions A and B. For example, proximal region A
may be provided with a multilayer coil, while distal region B may
be provided with a braid. Alternately, proximal region A may be
provided with a metallic braid, while distal region B may be
provided with a single layer coil. As discussed above, the
densities of the metallic members in the respective sections may be
varied considerably to select for a desired variable stiffness
profile, as will be appreciated by those of skill in the art.
[0107] In one preferred embodiment, variable stiffness along the
length of the tubular body is achieved by keeping the braid density
constant along the length of tubular body 16 and then forming the
proximal and distal portions of tubular body 16 of polymeric
materials of differing stiffness. For example, braid density may be
uniform and range from 60-80 picks/inch, more preferably be about
70 picks/inch, with region A being formed of 72D Pebax.TM. and
region B being formed of 25-50D Pebax.TM.. Alternately, region A
can be formed of high density polyethylene and region B of low
density polyethylene.
[0108] Moreover, any of a variety of different polymeric materials
known by those of skill in the art to be suitable for catheter body
manufacture may be used to form tubular body 16. For example,
tubular body 16 may be formed out of Pebax.TM., blends of
Pebax.TM., and nylons, polyetheretherketone (PEEK), polyethylenes,
and Hytrel.TM., and the like. Different materials might also be
combined or blended to select for desirable flexibility
properties.
[0109] Also, although tubular body 16 has been described in the
context of having two regions of differing flexibility, it will be
readily appreciated by those of skill in the art that three or more
regions of differing flexibility may easily be provided, by
adapting the teachings contained herein.
[0110] In the above-discussed embodiments, and all other
embodiments of the present invention, it may be preferred to
provide main lumen 30 and the outer surface of tubular body 16 with
a hydrophillic coating, a hydrophobic coating, or combinations
thereof. For example, main lumen 30 may be provided with a
hydrophobic coating, such as silicone, while tubular body 16 is
provided with a hydrophillic coating, such as polyvinyl pyrrolidone
(PVP), polyurethane blends, copolymers of acrylonitrile, and the
like. Other hydrophobic and hydrophillic coatings, as known to
those of skill in the art, may also be used. In addition, any of a
variety of antithrombogenic coatings, such as heparin, may also be
applied to the catheter of the present invention, alone or in
combination with other coating types.
[0111] Referring to FIGS. 4 and 5, there is illustrated a
cross-sectional view of the distal end 14 of catheter 10. Distal
end 14 is provided with a soft distal tip 50, which is not
preformed with tubular body 16, but is instead attached to tubular
body 16 as a tube post manufacturing step. Distal tip 50 is
preferably soft enough and flexible enough, so as to minimize
trauma to body vessels as catheter 10 is advanced, and also to
facilitate navigation of catheter 10 in tortuous vessels. In one
preferred embodiment, distal tip 50 is formed as a 0.5 cm sleeve of
25-40D Pebax.TM., and is bonded to tubular body 16 by heat fusing.
Alternately, distal tip 50 may be attached to tubular body 16 by
adhesives, or by insert molding, as is known to those of skill in
the art. Preferably, distal tip 50 is in alignment with tubular
body 16, and does not bend or curve, such that the radial axis of
distal tip 50 is substantially the same as that of tubular body
16.
[0112] The distal end 14 of catheter 10 is also preferably provided
with a radiopaque material 44. Advantageously, radiopaque material
44 serves as a marker to help the clinician position catheter 10
during a medical procedure. Various well-known radiopaque materials
may be used in distal end 14, such as platinum, gold, and
platinum-iridium blends. The full length, or part of the length of
the tubular body, may also be radiopaque by blending radiopaque
materials in the polymeric materials used to form the body.
Furthermore, radiopacity of the tip can also be achieved by loading
(i.e., comparing) the distal tip 50 with a sufficient amount of
barium sulfate. Alternatively, bismuth subcarbonate, bismuth
trioxide or bismuth oxychloride may be used as a radiopaque filler.
Also, radiopacity may be achieved by using radiopaque wire or flat
ribbon to make the braid or coil.
[0113] Illustrated in FIGS. 6-9, there is an emboli containment
system utilizing catheter 10 of the present invention. Catheter 10
of the present invention is used in the treatment of a stenosis 55
in a lumen 50 in a blood-carrying vessel 58 in which the stenosis
55 at least partially occludes the lumen 50. The emboli containment
system depicted in FIG. 6 comprises a catheter 10, as described
above, as well as catheters 100 and 200.
[0114] Catheter 100 comprises an elongate flexible tubular body 116
having proximal end and distal end 114. An inflatable balloon 126
of the same type as inflatable balloon 26 is coaxially mounted on
tubular body 116 on the end 114 of catheter 100. The tubular body
116 has centrally disposed inflation lumen 132 in fluid
communication with balloon 126, such that fluid passing through
lumen 132 may be used to inflate balloon 126. Alternatively, fluid
may be withdrawn from lumen 132 to deflate balloon 126. As shown in
FIG. 6, catheter 100 is disposed within main lumen 30 of catheter
10 and is slidably and coaxially mounted therein for variable
displacement of balloon 126 with respect to the first balloon 26,
as hereinafter described. One preferred embodiment of a catheter
100 is disclosed in our co-pending application, entitled HOLLOW
MEDICAL WIRES AND METHODS OF CONSTRUCTING SAME, Ser. No.
08/812,876, filed Mar. 6, 1997, now U.S. Pat. No. 6,068,623, the
entirety of which is incorporated by reference.
[0115] The emboli containment system also comprises catheter 200
comprising an elongate flexible tubular body 216 having proximal
end and distal end 214. Catheter 200 is also provided with a
generally centrally disposed lumen 230 extending from the proximal
end to the distal end of catheter 200, and through which catheter
100 is coaxially and slidably mounted.
[0116] The distal end 214 of catheter 200 is provided with means
for performing a medical procedure, such as an apparatus for
treating stenotic lesion 55. In the embodiment of the invention
shown in FIG. 6, this means comprises a dilatation balloon 226,
which is preferably a non-compliant inflatable balloon which is
coaxially mounted on the distal end 214 of catheter 200. Balloon
226 may also be attached to tubular body 216 in the same manner as
balloons 26 and 126 hereinbefore described. Tubular body 216 is
provided with a balloon inflation lumen 232 which is in fluid
communication with balloon 226, such that balloon 226 may be
inflated by the passage of fluid through lumen 232.
[0117] The operation and use of the emboli containment system
utilizing the catheter of the present invention for treating
occluded vessels may now be briefly described in connection with an
occlusion formed by a stenosis in a carotid artery, as illustrated
in FIGS. 10A-E.
[0118] Catheter 100 is inserted into an incision into a femoral
artery of a patient and is advanced through that artery into the
aorta of the patient and into the ostium of the carotid artery to
be treated. After catheter 100 has been introduced, catheters 10
and 200, with balloons 26 and 226 completely deflated, are
introduced over catheter 100 and are advanced into the ostium of
the carotid artery and into the lumen or passageway of the vessel
as shown in FIGS. 10A-E.
[0119] The emboli containment system is advanced until catheter 10
is proximal of a stenosis 55 in the vessel lumen 50 to be treated.
Balloon 26 is then inflated by introducing a suitable inflation
medium such as a radiopaque liquid into port 18 to cause it to pass
through the balloon inflation lumen 32 to inflate balloon 26, as
shown in FIG. 10B. Balloon 26 is progressively inflated until it
engages the side wall 58 of the vessel to occlude the lumen 50.
[0120] Catheter 100 is then advanced through stenosis 55 as shown
in FIG. 10C. Catheter 100 with deflated balloon 126 thereon is
advanced through stenosis 55 until the balloon 26 is distal of
stenosis 55 as shown in FIG. 10D. Balloon 126 is then inflated by
passing an inflation medium through lumen 132 to the interior of
the balloon 126 to inflate the balloon 126 until it engages the
sidewall 58 of the vessel lumen 50. As soon as the balloon 126 has
been inflated, a working space is provided between balloons 26 and
126, so that medical procedures can be undertaken to remove or
reduce the stenosis 55 in the space between second balloons 26 and
126, without risk of unwanted particles or emboli escaping into the
blood stream.
[0121] For emboli containment systems featuring balloon dilatation
treatment, it is desired to compress the plaque or material forming
the stenosis to provide a larger vessel. Thus, catheter 200 is
advanced over catheter 100 to cause distal end 214 with balloon 226
thereon to be advanced into the working space. As soon as balloon
226 has been properly positioned within stenosis 55, balloon 226 is
inflated with a suitable inflation medium, as for example a
radiopaque liquid. Balloon 226 can be inflated to the desired
pressure to cause compression of the plaque of the stenosis 55
against the sidewall 58 of lumen 50 by the application of
appropriate inflation pressure. As in conventional angioplasty
procedures, balloon 226 can be formed of a non-elastic relatively
non-compliant material so that appropriate pressures, such as 10-15
atmospheres, can be used within balloon 226 to apply compressive
forces to the vessel without danger of rupturing the vessel. It
should be appreciated that the non-elastic capabilities can also be
achieved by a composite elastic material.
[0122] Once the clinician is satisfied that the occlusion forming
stenosis 55 has been sufficiently compressed, balloon 226 can be
deflated. After the appropriate dilation of stenosis 55 has been
accomplished, catheter 200 can be removed from the stenosis.
Moreover, in one preferred method, catheter 200 is completely
withdrawn from the emboli containment system, and an irrigation
catheter is inserted over catheter 100 and through lumen 30, as
described in our copending application entitled METHOD FOR EMBOLI
CONTAINMENT, Ser. No. 08/812,875, filed Mar. 6, 1997, now U.S. Pat.
No. 5,833,644, the entirety of which is incorporated by reference.
Fluid introduced into the working space may be removed by supplying
a negative pressure or suction to aspiration port 20. This creates
a negative pressure within space 30a defined by the interior
surface of lumen 30 and outer tubular body 216, to suck or aspirate
blood or other fluids in lumen 50 into space 30a and out of
aspiration port 20. In this manner, irrigation and aspiration of
the working space may take place so that any plaque coming off the
occlusion forming the stenosis 55 can be aspirated out of the
vessel. Subsequently, balloon 26 and balloon 126 can be deflated to
permit normal blood flow through the vessel lumen 50. The entire
catheter assembly can then be removed and a suture applied to the
incision created to obtain access to the femoral artery.
[0123] In general, the catheter apparatus is for treatment of a
stenosis in a lumen in a blood carrying vessel. It is comprised of
a main catheter and a balloon-on-a-wire device. The main catheter
is comprised of a first flexible elongate tubular member having
proximal and distal extremities. A first inflatable elastic balloon
having an interior is coaxially mounted on the distal extremity of
the first flexible elongate tubular member. The first flexible
elongate tubular member has a balloon inflation lumen therein in
communication with the interior of the first balloon. The first
elongate tubular member has a main lumen therein extending from the
proximal extremity to the distal extremity and exiting through the
distal extremity. An adapter is mounted on the proximal extremity
of the first flexible elongate tubular member and has a balloon
inflation port in communication with the balloon inflation lumen, a
therapeutic catheter port and an aspiration port in communication
with the main lumen. The balloon-on-a-wire device is comprised of a
guide wire having proximal and distal extremities.
[0124] A second inflatable elastic balloon has an interior and is
coaxially mounted on the distal extremity of the guide wire. The
guide wire has a balloon inflation lumen therein in communication
with the interior of the second balloon. The balloon-on-a-wire
device is slidably mounted in the therapeutic catheter port and in
the main lumen of the first elongate tubular member with the
proximal extremity of the guide wire being disposed outside of the
main lumen. Removable valve means is carried by the proximal
extremity of the guide wire and has the capability of forming a
fluid-tight seal with respect to the guide wire while permitting
relative axial movement of the guide wire and the first flexible
elongate tubular member with respect to each other whereby the
first balloon can be moved so that it is proximal of the stenosis
and the second balloon so that it is distal of the stenosis. The
removable valve means includes an inflation port in communication
with the balloon inflation lumen and the guide wire. The apparatus
is also comprised of means coupled to the balloon inflation port of
the first flexible elongate tubular member for inflating the first
balloon and means coupled to the balloon inflation port of the
removable valve means for inflating the second balloon to create a
working space which brackets the stenosis.
[0125] More particularly as shown in FIGS. 11-14, the catheter
apparatus 311 of the present invention is for use in the treatment
of a stenosis 312 in a lumen 313 in a blood-carrying vessel 314 in
which the stenosis 312 has a length and a width or thickness which
at least partially occludes the lumen 313. The apparatus consists
of a first elongate flexible tubular member 316 formed of a
suitable plastic material which is provided with proximal and
distal extremities 317 and 318. A first balloon 319 is mounted on
the distal extremity 318 and preferably is a compliant balloon
formed of a suitable elastic material such as a latex or a very low
radiation polyethylene so that it can be inflated to the size of
the vessel 314 in which it is to be disposed. Thus, the balloon 319
should be capable of expanding to various diameters depending on
the size of the vessel. The first balloon 319 can be formed as a
separate balloon separate from the elongate tubular member 316 as
shown and adhered thereto by suitable means such as an adhesive
(not shown), or it can be formed integral with the tubular member
16 in a manner well known to those skilled in the art.
[0126] The tubular member 316 is provided with a large centrally
disposed or main lumen 321 extending from the proximal extremity
317 to the distal extremity 318. It is also provided with a balloon
inflation lumen 322 which has a distal extremity in communication
with the interior of the first balloon 319 through a port 323. The
proximal extremity of the balloon inflation lumen 322 is in
communication with a balloon inflation fitting 324 mounted on the
proximal extremity 317 of the tubular member 316. The fitting 324
can be of a conventional type as for example a Luer-type fitting
which is adapted to be connected to a balloon inflation device (not
shown) for inflating and deflating the first balloon 319.
[0127] The first tubular member 316 is also provided with an
aspiration lumen 326 which exits through the distal extremity 318
and the proximal extremity 317 of the tubular member 316. A
Luer-type fitting 327 is mounted on the proximal extremity 317 and
is in communication with the aspiration lumen 326. The fitting 327
is adapted to be connected to a suitable aspiration or suction
source (not shown) of a conventional type such as a syringe or
rubber bulb for aspiration purposes as hereinafter described.
[0128] The catheter assembly or apparatus 311 also consists of a
second elongate flexible tubular member 331 having proximal and
distal extremities 332 and 333. A second inflatable balloon 336 of
the same type as the first inflatable balloon is coaxially mounted
on the distal extremity 333 in a conventional manner. The tubular
member 331 is provided with a large generally centrally disposed
arterial blood flow lumen 337 which opens through the distal
extremity 333 and is in communication with a Luer-type fitting 338
which as hereinafter described is adapted to be connected to a
supply of arterial blood from the patient which for example can be
taken from another femoral artery of the patient by the use of a
blood pump.
[0129] The second tubular member 331 is also provided with a
balloon inflation lumen 339 which is in communication with the
interior of the second inflatable balloon 336 through a port 341.
The proximal extremity of the lumen 339 is in communication with
the Luer-type fitting 342 mounted on the proximal extremity 332 of
the second tubular member 31 and as with the balloon inflation
fitting 324 is adapted to be connected to a balloon
inflation-deflation device (not shown) of a conventional type. The
second tubular member 331 is also provided with a lumen 343 which
also can be used as a guide wire and/or for introducing a saline
solution extending from the proximal extremity to the distal
extremity. The lumen 343 is sized so that it is adapted to receive
a conventional guide wire 346 as for example a 0.014" or 0.018"
guide wire and extends from the proximal extremity to the distal
extremity so that the guide wire 346 can extend beyond the distal
extremity of the second tubular member 331. A fitting 347 is
provided on the proximal extremity 332 in communication with the
lumen 343 for introducing the saline solution.
[0130] As shown in FIG. 11, the second tubular member 331 is
disposed within the central lumen 321 of the first tubular member
316 and is slidably and coaxially mounted therein for displacement
of the second balloon 336 with respect to the first balloon 319 as
hereinafter described.
[0131] The catheter assembly or apparatus 311 also consists of a
third elongate flexible tubular member 351 having proximal and
distal extremities 352 and 353. It is provided with a centrally
disposed lumen 356 extending from the proximal extremity 352 to the
distal extremity 353 and through which the second tubular member
331 is coaxially and slidably mounted.
[0132] Means 357 is provided on the distal extremity 353 of the
third tubular member 351 for performing a medical procedure. In the
embodiment of the invention shown in FIG. 11, this means 357
consists of a third balloon 358 which can be non-compliant
coaxially mounted on the distal extremity of the third tubular
member 351. The third balloon 358 can be attached in the same
manner as the first and second balloons 319 and 336 hereinbefore
described. The third tubular member 351 is provided with a balloon
inflation lumen 359 which has its distal extremity in communication
with the interior of the balloon 358 through a port 361. The
proximal extremity of the balloon inflation 359 is in communication
with a Luer-type fitting 362 provided on the proximal extremity 352
and adapted to be connected to a conventional inflation deflation
device (not shown) for inflating and deflating the third balloon
358.
[0133] The operation and use of the catheter assembly or apparatus
311 in the method of the present invention for treating occluded
vessels may now be briefly described in connection with an
occlusion formed by a stenosis in a vessel not having a bifurcation
therein as for example in saphenous graft or in one of the right
and left carotid arteries, also called internal and external
carotid arteries, of a patient in connection with the illustrations
shown in FIGS. 15 and 16A-16E. A guiding catheter 363 (FIG. 15) of
a conventional type is inserted into an incision into a femoral
artery 364 of a patient and is advanced through that artery into
the aorta of the heart 365 of the patient and into the ostium 366
of the selected carotid artery or vessel as for example the left
carotid 367.
[0134] After the guiding catheter has been appropriately
positioned, the guide wire 346 is introduced separately into the
guiding catheter or along with the catheter assembly 311. The
distal extremity of the catheter apparatus or assembly 311 with all
of the first, second and third balloons 319, 336 and 358 completely
deflated, is introduced into the guiding catheter 363 along with or
over the guide wire 346 and is advanced through the guiding
catheter 363 into the ostium 366 of the carotid artery or vessel
367 and into the lumen or passageway 368 of the vessel as shown in
FIGS. 15 and 16B.
[0135] The distal extremity of the catheter assembly 311 is
advanced until it is just proximal of a stenosis 369 in the carotid
artery 367 to be treated. The balloon 319 is then inflated by
introducing a suitable inflation medium such as a radiopaque liquid
into the fitting 324 to cause it to pass through the balloon
inflation lumen 322 through the port 323 and into the interior of
the first balloon 319 to inflate the same as shown in FIG. 16B. The
balloon 319 is progressively inflated until it engages the side
wall of the vessel 367 to occlude the vessel 367. At the time that
this is occurring, a negative pressure or suction is applied to the
aspiration fitting 327 to supply a negative pressure through the
balloon inflation lumen 322 to suck or aspirate blood in the vessel
367 distal of the first balloon 319 into the aspiration lumen 326
and out the aspiration fitting 327 to thereby reverse the flow of
blood through the stenosis as shown by the arrows 371 in FIG.
16B.
[0136] While a reverse flow of blood is occurring in the vessel
367, the guide wire 346 is advanced through the stenosis 369 as
shown in FIG. 16C. In the event that any pieces or particles of
plaque are knocked off of the occlusion formed by the stenosis 369
by movement of the guide wire 346 through the same, such pieces of
plaque or emboli will be drawn out with the reverse flow of blood
into the aspiration lumen 326 and out of the aspiration fitting
327. During the time that the guide wire 346 is being advanced
through the stenosis 369 it may be desirable at the same time to
introduce a saline solution through the guide wire lumen 343 of the
second elongate flexible tubular member 331 to exit through the
distal extremity of the second elongate flexible tubular member 331
into the space immediately proximal of the stenosis 369. This
introduced saline solution aids the flow of particulate or other
particles dislodged from the stenosis 369 during advancement of the
guide wire 346 through the same and carries them back with the
mixed saline blood solution through the aspiration lumen 326 in a
manner hereinbefore described.
[0137] With the guide wire 346 remaining in position, the second
elongate flexible tubular member 331 with the second balloon 336
thereon in a deflated condition is advanced over the guide wire 346
through the stenosis 369 until the second balloon 336 is distal of
the stenosis 369 as shown in FIG. 16D after which the second
balloon 336 is inflated by introducing an inflation medium as for
example a radiopaque liquid through the inflation fitting 342 into
the lumen 339 through the port 341 to the interior of the second
balloon 336 to inflate the second balloon 336 until it engages the
sidewall of the vessel 367.
[0138] Prior to, during or after inflation of the second balloon
336, the guide wire 346 can be removed. However, it is preferable
to remove the guide wire 346 as soon as the second balloon 336 has
been advanced so that it is beyond the stenosis 369. At this time,
and certainly prior to complete inflation of the second balloon
336, blood is shunted across the stenosis 369 and into the lumen
368 distal of the second balloon 336 by introducing blood through
the fitting 338 and into the centrally disposed blood flow lumen
337 in the second tubular member 331 so that it exits out the
central lumen 337 distal of the second balloon 336. The blood which
is supplied to the fitting 337 can be taken from another femoral
artery of the patient and pumped into the fitting 338. In addition,
if desired, the blood which is aspirated in the space distal of the
first balloon 319 can be appropriately filtered and also supplied
to the fitting 338. By shunting blood past the stenosis 369 in this
manner it can be seen that blood is being continuously supplied to
the carotid artery of the patient during the time that the second
balloon 336 is inflated and occludes the lumen 368 in the vessel
367.
[0139] As soon as the second balloon 336 has been inflated, it can
be seen that there is provided a working space 376 (FIG. 16D)
between the first and second balloons 319 and 336 so that medical
procedures can be undertaken to remove or reduce the stenosis 369
in the space between the first and second balloons 319 and 336.
[0140] Assuming that it is desired to compress the plaque or
material forming the stenosis 369 to provide a larger lumen,
opening or passageway through the stenosis 369 the third tubular
member 51 can be advanced by grasping the proximal extremity 352 to
cause the distal extremity with the third balloon 358 thereon to be
advanced into the working space 376. As soon as the balloon 358 has
been properly positioned within the stenosis 369, the balloon 358
also can be inflated with a suitable inflation medium as for
example a radiopaque liquid. The balloon 358 can be inflated to the
desired pressure to cause compression of the plaque of the
occlusion against the sidewall of the vessel 367 by the application
of appropriate pressure. As in conventional angioplasty procedures,
the third balloon 358 can be formed of a non-elastic relatively
non-compliant material so that high pressures as for example 10-15
atmospheres can be used within the balloon to apply compressive
forces to the vessel without danger of rupturing the vessel. It
should be appreciated that the non-elastic capabilities can also be
achieved by a composite elastic material.
[0141] Since the blood flow has been restored to the vessel 367 by
the shunt hereinbefore described, the compression of the occlusion
forming the stenosis 369 can be carried out for an extended period
of time, as for example after a few minutes, if desired to help
ensure that a large lumen or passageway is formed through the
stenosis 369 as shown in FIG. 16E. If it is believed that the
occlusion forming the stenosis 369 has been sufficiently
compressed, the third balloon 358 can be deflated. In the event an
inelastic balloon is utilized for the third balloon 358, and it is
desired to utilize a larger third balloon, this can be accomplished
by removing the third tubular member 351 with the deflated balloon
358 thereon and introducing a third tubular member 351 having a
larger size balloon thereon over the second tubular member 331 and
advancing it into the stenosis 369 and inflating the larger size
balloon to create a still larger passage through the stenosis
369.
[0142] After the appropriate dilation the stenosis 369 has been
accomplished the third balloon can be removed from the stenosis
while aspiration of the working space 376 is still ongoing so that
any plaque coming off the occlusion forming the stenosis 369 can be
aspirated out of the vessel. After the third balloon 358 has been
removed from the stenosis, the second balloon 336 and the first
balloon 319 can be deflated to permit normal blood flow through the
vessel 367 after which the arterial blood flow supply to the
fitting 338 can be terminated. The entire catheter assembly 311 can
then be removed from the guiding catheter 363 after which the
guiding catheter 363 can be removed and a suture applied to the
incision created to obtain access to the femoral artery.
[0143] In place of the third balloon 358 for causing compression of
the occlusion forming the stenosis 367 to create a larger
passageway therethrough, an atherectomy device 381 (see FIG. 17)
can be utilized for operating in the working space 376 to remove
the plaque of the occlusion forming the stenosis. This can be
accomplished with a catheter assembly or apparatus 381 which in
many respects is similar to the apparatus 311 shown in FIG. 11 and
consists of a first tubular member 316 with a first balloon 319 and
a second tubular 331 with a second balloon 336 thereon. In place of
the third flexible elongate tubular member 351 there is provided a
third flexible elongate tubular member 386 which is provided with
proximal and distal extremities 387 and 388. The flexible elongate
tubular member 386 is slidably and rotatably mounted in the central
lumen 321 of the flexible elongate member 316 and is provided with
a central or main lumen 389 through which the second flexible
elongate tubular member 331 extends. It is also provided with a
lumen 391 extending from the proximal extremity to the distal
extremity through which a saline solution can be introduced for
saline irrigation as hereinafter described. It is also provided
with another lumen 392 which is adapted to receive a plurality of
electrical conductors 393 for performing electrical functions as
hereinafter described. The lumen 392 is connected to a conventional
Luer-type fitting 396 serving as a fluid irrigation fitting mounted
on the proximal extremity first tubular member 312 and is in
communication with an annular recess 397 which is in communication
with the lumen 391 provided in the tubular member 386 for supplying
a saline irrigation liquid through the flexible elongate tubular
member 386 and into the working space 376 provided between the
first and second balloons 316 and 336. In order to aid aspiration
of the saline irrigation liquid from the working space 376, the
outer surface of the flexible elongate tubular member 386 is
provided with a helical groove 398 therein which has one end which
opens into the working space 376 and which has the other end in
communication with the aspiration fitting 327.
[0144] Means is provided for rotating the second tubular member 386
and consists of suitable means such as a spur gear 401 mounted on
the proximal extremity 387 of the tubular member 386. The spur gear
401 is driven in a suitable manner as for example by another
smaller spur gear 402 which is of greater width than spur gear 401
so as to provide a splined gear connection between the gears 401
and 402. This accommodates the desired longitudinal movement for
the tubular member 386 so that the distal extremity 388 of the
tubular member 386 can be advanced and retracted in the working
space 376 as hereinbefore described. An electrical drive motor 403
is provided for driving the gear 402.
[0145] Atherectomy means 406 is provided on the distal extremity
388 of the flexible elongate tubular member 386. As shown in FIGS.
17 and 19, the atherectomy means 406 consists of a flexible
elongate member 407 formed of a suitable material such as stainless
steel or preferably a superelastic Nitinol. The flexible elongate
member 407 is wound into a helix as shown in FIG. 19 onto the
distal extremity of the tubular member 386. The flexible elongate
member 407 can be formed of a ribbon having a thickness of 0.003"
and a width of 0.060". One end of the flexible elongate member 407
can be secured to the tubular member 386, as for example by
inserting the same into a slit 408 and additionally by the use of
adhesive (not shown). The flexible elongate member 407 is wrapped
into a helix in a direction opposite to the direction of normal
rotation of the tubular member 386 and can be provided with a
special tip 409 on its free end with the tip having an arcuate
surface 411 that is inclined rearwardly to terminate at a cutting
edge 412 (see FIG. 19) which is adapted to engage the plaque or the
stenosis 369.
[0146] When the distal extremity 388 of the flexible elongate
tubular member 386 has been introduced into the working space 376,
the end or tip 409 of the flexible elongate member 407 of the
atherectomy means 406 is free. A saline solution is introduced into
the fitting 357. Thereafter the motor 403 can be energized to cause
rotation of the tubular member 386 and to thereby cause rotation of
the helically wound flexible elongate member 407 to cause its free
end or tip 409 to be moved outwardly radially under centrifugal
force to bring the cutting edge 412 into engagement with the plaque
369 in the stenosis 369 to cause progressive removal of the plaque
forming the stenosis 369 to enlarge the passageway extending
through the stenosis. Because of the rounded configuration of the
tip 409, the tip 409 will not dig into the vessel wall but will
only remove plaque which is engaged by the cutting edge 412. As the
plaque is being removed, the saline solution introduced through the
fitting 396 into the space 376 picks up the plaque particles or
emboli as they are being removed. The saline solution with the
plaque or emboli therein is removed through the spiral groove 398
and through the aspiration port 327. The flexible elongate tubular
member 386 can be moved back and forth so that the cutting tip 409
engages the length of the stenosis 369 so that substantially all of
the stenosis 369 can be removed.
[0147] Means is provided to sense when sufficient plaque has been
removed from the stenosis 369 and to ensure that cutting edge 412
does not cut into the vessel wall. An ultrasonic sensor 416 (see
FIG. 17) is mounted in the distal extremity of the tubular member
386 and is connected by conductors 393 (see FIG. 18) extending
through the lumen 392 and connected to a cable 418 which is
connected to an ultrasonic power supply 419 and a video monitor
421. By using the Doppler effect, ultrasonic energy can be utilized
in connection with the transducer 416 to ascertain the depth of cut
being made by the flexible elongate member 407 as it is being
rotated.
[0148] As soon as a desired amount of plaque has been removed from
the stenosis 369 to provide the desired passage through the
stenosis, rotation of the tubular member 386 is terminated after
which the tubular member 386 can be withdrawn followed by deflation
of the second balloon 336 and withdrawing it. Deflation of the
first balloon 316 then occurs after which it is withdrawn from the
vessel 367. Thereafter, the guiding catheter 363 can be removed and
the incision closed as hereinbefore described.
[0149] In order to ensure that restenosis will not take place, it
may be desirable to place a cylindrical stent 426 in the stenosis
369. Such a stent 426 can be a self-expanding stent formed of a
suitable material such as a superelastic Nitinol and movable
between unexpanded and expanded conditions. Such a stent 426 can be
placed by a suitable catheter apparatus 431 of the type shown in
FIG. 20. The stent 426 which is cylindrical in form is pushed over
the proximal extremity of the second elongate flexible tubular
member 331 into the main or central lumen 321 so that it is
retained in the unexpanded position. It is then pushed forwardly
toward the distal extremity of the first flexible elongate tubular
member 316 by means of a flexible elongate tubular member 436
having proximal and distal extremities 437 and 438 and having a
flow passage 439 extending from the proximal extremity 437 to the
distal extremity 438. The proximal extremity 437 is provided with a
knurled collar 441 which is adapted to be engaged by the hand to
facilitate pushing of the flexible elongate tubular member 436 so
that its distal extremity is in engagement with the stent 426.
Thus, when desired the stent 426 may be discharged or dislodged
from the distal extremity of the second tubular member 331 and
pushed into the working space 376 created between the first balloon
319 and the second balloon 336.
[0150] After the stent 426 has been discharged out of the end of
the first flexible elongate tubular member 316, the stent 426 will
self expand toward its expanded condition until it is in engagement
with the wall of the vessel in the vicinity of the occlusion
forming the stenosis 369 to frictionally retain the stent in
engagement with the vessel wall. As soon as the stent 426 is in
engagement with the vessel wall, the second balloon 336 can be
deflated as can the first balloon 319. The first deflated balloon
336 can then be withdrawn through the interior of the cylindrical
stent 426. This can be followed by deflation of the first balloon
319 and the removal of the flexible elongate tubular member 316
with its first balloon 319 and the flexible tubular member 331 with
its second balloon 336, along with the flexible elongate member 436
until the entire catheter assembly or apparatus 431 has been
removed from the guiding catheter 363. Thereafter the guiding
catheter 363 can be removed and the incision sutured as
hereinbefore described.
[0151] In FIG. 21, there is shown another embodiment of an
apparatus 451 incorporating the present invention which is
particularly adapted for use treating a stenosis at or near a
bifurcation appearing in an arterial vessel. The apparatus 451 is
shown being used on a human being 452 showing the principal
arteries and pulmonary veins of the human body. Thus there as
shown, the abdominal aorta 453 branches into the common iliac 454
which branches into the external iliac 456 and the internal iliac
457. The external iliac branches into the deep femoral artery 458
and into the femoral artery 459. The abdominal aorta 453 extending
in the opposite direction passes through the aortic arch 461 of the
heart 462. The aortic arch 461 is connected to the common carotid
466 which extends into a bifurcation 467 branching into the
external carotid 468 and the internal carotid 469. Similar
bifurcations appear in the basilar artery which is an artery which
is particularly inaccessible for surgical treatment.
[0152] As hereinafter explained, the apparatus 451 shown in FIGS.
21, 22 and 23 consists of a proximal occlusion balloon catheter 476
which can be considered to be a first catheter. The catheter 476 is
formed of a flexible elongate tubular member 477 having proximal
and distal extremities 478 and 479. The tubular member 477 is
formed of a suitable material such as plastic and can have a
suitable size ranging from 5 to 14 French and preferably 9 to 10
French. A balloon 481 is provided on the distal extremity 479 and
is formed of a suitable elastic material. It is generally
cylindrical in form and has its proximal and distal extremities
secured to the tubular member 477 by suitable means such as an
adhesive (not shown). The tubular member 477 is provided with a
plurality of lumens therein. One lumen 482 serves as a balloon
inflation lumen and extends from the proximal extremity 478. It can
have a suitable size such as 0.024" and has port 483 in
communication with the interior of the balloon 481. A manifold 486
formed of a suitable material such as plastic is mounted on the
proximal extremity 478. A tubular member 487 is mounted in the
manifold 486 and is in communication with the inflation lumen
482.
[0153] The tubular member 477 is also provided with a large lumen
491 having a suitable size as for example 0.045" which is adapted
to slidably receive therein a therapeutic balloon catheter 492 and
a perfusion balloon catheter 493. It is also provided with another
lumen 496 having a suitable size as for example 0.026" which is
adapted to receive a balloon-on-a-wire catheter 497. It is also
provided with an aspiration lumen 501 having a suitable size as for
example 0.025" and an irrigation lumen 502 having a suitable size
as for example 0.015". There is also provided another lumen 503
which can be used for other purposes.
[0154] The therapeutic balloon catheter 492 and the perfusion
balloon catheter 493 are constructed in a manner similar to the
balloon catheters hereinbefore described. Thus the perfusion
balloon catheter 493 is provided with a flexible elongate tubular
member 506 having proximal and distal extremities 507 and 508. A
balloon 509 formed of an elastic material is secured to the distal
extremity 508 by suitable means such as an adhesive (not shown) and
is adapted to be inflated through a port 510 in communication with
a balloon inflation lumen 511. The tubular member 506 is also
provided with a blood perfusion lumen 512 which is centrally
disposed therein. The proximal extremity 507 of the tubular member
506 is connected to a Y adapter or fitting 513 of which the central
arm 514 is in communication with the blood perfusion lumen 512 and
is provided with a Luer-type fitting 516. The side arm 517 of the
fitting 513 is in communication with the balloon inflation lumen
511 and is provided with a Luer-type fitting 518 adapted to be
connected to a source of pressure as hereinafter described.
[0155] The therapeutic balloon catheter 492 consists of a tubular
member 521 having a proximal and distal extremities 522 and 523. A
balloon 524 formed of a non-elastic material is secured to the
distal extremity 523 by suitable means such as an adhesive. A port
(not shown) is in communication with the interior of the balloon
524 and is in communication with a balloon inflation lumen 526. A
Luer-type fitting 527 is mounted on the proximal extremity 522 and
is in communication with the balloon inflation lumen 526. Another
fitting 528 is mounted on the proximal extremity 522 and is in
communication with a large centrally disposed lumen 529 which can
receive the perfusion balloon catheter 493 for slidable movement as
hereinafter described.
[0156] The balloon-on-a-wire catheter 497 is slidably mounted in
the lumen 496 and consists of a guide wire 531 of a conventional
construction having a suitable diameter as for example 0.018" and
having a proximal and distal extremities 532 and 533. A balloon 534
formed of a non-elastic material is mounted on the distal extremity
533 and is secured thereto by suitable means such as an adhesive
(not shown). The proximal extremity of the balloon 534 is secured
to the distal extremity of a tubular member 536 formed of a
suitable material such as plastic and which is coaxially disposed
on the guide wire 531. The tubular member 536 extends the length of
the guide wire to the proximal extremity and is connected to a
Luer-type wye fitting 537 and is in communication with an annular
lumen 538 disposed between the tubular member 536 and the exterior
surface of the guide wire 531. The lumen 538 is in communication
with the interior of the balloon 534 for inflating and deflating
the balloon 534. The balloon-on-a-wire catheter 497 is adapted to
be introduced through a fitting 541 carried by a tube 542 mounted
in the manifold 486 and in communication with the lumen 496 in the
multi-lumen elongate tubular member 477.
[0157] A tube 546 is mounted in the manifold 486 and is in
communication with the large lumen 491 and is provided with a
fitting 547 which is adapted to receive the perfusion balloon
catheter 493 and the therapeutic balloon catheter 492 as
hereinafter described. Another tube 551 is provided in the manifold
486 and is in communication with the aspiration lumen 501. It is
provided with the fitting 552. Another tube fitting 553 is mounted
in the manifold 486 and is in communication with the irrigation
lumen 502 and is provided with a fitting 554.
[0158] The various fittings for the catheter as hereinbefore
described are adapted to be connected into a control console 571.
The control console 571 consists of a rectangular case 572 which is
provided with a front panel 573.
[0159] A plurality of balloon inflation deflation devices 576 of a
conventional type typically called endoflaters are mounted within
the case 572 and have control handles 577 extending through
vertically disposed slots 578 provided in the front panel. These
endoflaters 576 are labeled as shown in FIG. 21 and are connected
by tubing (not shown) through pressure gauges 581 mounted in the
front panel 573 and are provided with needle indicators 582 to
indicate the pressure being applied by the endoflater to the
tubing. The tubing is connected in such a manner so that the
endoflater 576 and the associated pressure gauge 581 are connected
to a tube 586 which is provided with a mating fitting 587 adapted
to mate with a fitting 488 so that it is in communication with the
inflation lumen 482 of the proximal occlusion balloon catheter 476.
In a similar manner, the tubing 588 is provided with a fitting 589
which mates with a fitting 518 of the balloon inflation lumen 511
of the perfusion balloon catheter 493 for inflating balloon 509.
Similarly, tube 591 with its mating fitting 592 is adapted to mate
with the fitting 537 for inflating the balloon 534. Similarly, the
tube 593 with its fitting 594 mates with the fitting 527 in
communication with the balloon inflation lumen 526 for inflating
the balloon 524 of the therapeutic catheter 492. Another tube 596
which is provided with its fitting 597 mates with the fitting 552
that is in communication with the aspiration lumen 501. The tube
596 is in communication with the inlet of a blood pump 601 of a
suitable type as for example a roller pump well known to those
skilled in the art which is mounted within the case 572 and which
is connected to a source of electrical power through electrical
plug 602 connected into the case 572. The roller pump 601 is
provided with an on/off switch 603 mounted on the front panel 573.
After it passes through the pump 601, blood is supplied to a blood
filter 606 of a conventional type and then is supplied through a
tube 611 having a fitting 612 adapted to mate with the fitting 516
of the perfusion balloon catheter which is in communication with
the perfusion lumen 512.
[0160] A three-way valve 616 is associated with each of the
endoflaters 576 and has a control knob 617 extending through the
front panel 573 and is adaptable to be moved between three
positions with a center off position and an aspiration position in
a counter-clockwise direction and a pressurized position in a
clockwise position as viewed in FIG. 24.
[0161] Operation and use of the apparatus 451 may now be briefly
described as follows. Let it be assumed that it is desired to treat
a stenosis occurring in a bifurcation in a carotid artery as
depicted by the illustrations shown in FIGS. 25A through 25D. As
shown in the illustration in FIG. 25A, let it be assumed that a
stenosis is present adjacent the bifurcation 467 and in the
external carotid 468 and that it is desired to treat this stenosis
in accordance with the apparatus 451 of the present invention in
performing the method of the present invention. The proximal
occlusion balloon catheter 476 is loaded with the therapeutic
balloon catheter 492 slidably mounted over the perfusion balloon
catheter 493 and both are slidably mounted in the main lumen 491.
The balloon-on-a-wire catheter 497 is slidably mounted in the
lumen. While the patient is being prepared for the procedure, all
of the lumens in the catheters of the apparatus are flushed with
saline to remove all air from the lumens. They are then connected
to the control console 571 in the manner hereinbefore described and
as shown in FIG. 21. An incision 626 (see FIG. 21A) is made in the
femoral artery in the left leg of the patient and a guiding
catheter (not shown) similar to the type utilized in angioplasty is
introduced through the femoral artery 459. This guiding catheter is
advanced until it is near the aorta arch 461. Thereafter, the first
or proximal occlusion balloon catheter 476 has its distal extremity
479 introduced into the guiding catheter and advanced in the
guiding catheter. It is advanced so that its distal extremity 479
enters the common carotid and is near the bifurcation 467. The
balloon 481 is inflated by operating the control handle 577
associated with the proximal occlusion balloon 481 as shown in FIG.
25A to create the desired pressure within and to inflate the
elastic balloon 481 so that it occludes the common carotid just
proximal of the stenosis 624. As soon as this occurs, the roller
pump 601 is turned on by operating the on/off switch 603 to create
a negative pressure on the distal side of the balloon 481 to cause
blood to flow in a reverse direction as shown by arrows 627 to
thereby change the directional flow of blood from the internal and
external carotids away from the brain rather than to the brain. The
blood travels into the aspiration lumen 501 as indicated by the
arrows 627 and into the tube 551 through fittings 552 and 597 and
tube 596 to the roller pump 603. The blood after passing through
the roller pump 603 passes through a blood filter 606 and then
passes into the tube 611 and the fitting 612 and connected to the
fitting 589 of the perfusion catheter 493. Alternatively, the
fitting 612 can be which is connected to another fitting 631
mounted on a tube 632 introduced into the venous side of the
circulatory system of the patient's body, as for example into the
vein in the right leg of the patient 452 as shown in FIG. 21. Any
debris or emboli in the aspirated blood being pumped will be
filtered out by the blood filter 606.
[0162] As soon as or during the time this retrograde circulation of
blood is established through the roller pump 601, the perfusion
balloon catheter 493 extending proximally from the fitting 547 is
advanced into the internal carotid 469 past the stenosis 621 at the
bifurcation 467. If necessary, a guide wire can be utilized which
can be introduced through the perfusion lumen 512 to aide in
advancing the perfusion balloon catheter 493 into the internal
carotid 469. Any emboli or debris dislodged from the stenosis 621
by crossing the same either by the guide wire or by the distal
extremity of the catheter 493 will be picked up by the retrograde
flow of blood which is being aspirated through the proximal
occlusion balloon catheter 476 to thereby prevent any emboli or
debris from entering the brain of the patient. The elastic
perfusion balloon 509 is then inflated as shown in FIG. 25B using
the appropriate endoflater to inflate the balloon to the desired
pressure while watching the associated pressure gauge. As soon as
occlusion occurs, perfusion of blood can be started as hereinafter
described.
[0163] Prior to or after the balloon 509 of perfusion catheter 493
has been inflated, the balloon-on-a-wire catheter 497 extending
proximally of the fitting 541 is advanced into the external carotid
469 as shown in FIG. 25C. The balloon 534 is then expanded by use
of the appropriate endoflater to supply an inflating medium through
the fitting 537 to occlude the external carotid 469. As soon as
occlusion has been accomplished in both the external and internal
carotids, retrograde flow of blood is terminated by shutting off
the roller pump 601. It should be appreciated that if desired,
automatic controls can be provided whereby when a certain pressure
is reached in each of the balloons 509 and 534 the roller pump
would automatically be shut off to stop retrograde flow. By this
procedure, it can be seen that the lesion of stenosis 621 has been
bracketed by the balloons 481, 509 and 534. Prior to that
occurring, retrograde flow of blood is established to prevent any
emboli or debris from moving towards the brain.
[0164] As soon as retrograde flow of blood has been terminated,
perfusion of blood is started. This can be accomplished by
connecting a cannula (not shown) to the fitting 516 of the
perfusion catheter 506 and to obtain a supply of blood from the
femoral artery in the other leg of the patient. Alternatively, an
outside blood supply can be used. Thus fresh blood will be supplied
from the femoral artery of the patient directly into the perfusion
balloon so that it is discharged distally of the perfusion balloon
509 as shown by the arrows 628 to continue to supply blood to the
carotid artery. It has been found that it is unnecessary to a
supply perfusion of blood to the external carotid artery because
there is sufficient auxiliary circulation in that carotid artery
during the time the procedure is taking place.
[0165] In the event there is inadequate pressure on the arterial
blood being perfused to overcome the resistance in the lumen 469,
the roller pump 601 can be utilized by merely operating the same in
a reverse direction and connecting it between the cannula and the
perfusion catheter.
[0166] After the lesion or stenosis 621 has been bracketed as
hereinbefore described and a working space 636 formed adjacent the
stenosis or lesion 621, a therapeutic procedure can be employed. By
way of example this can consist of advancing the therapeutic
balloon catheter 492 over and axially of the perfusion catheter 493
to bring its balloon 524 into registration with the stenosis 621 as
shown in FIG. 25D. Thereafter, the balloon 524 can be inflated by
use of the appropriate endoflater as hereinbefore described to
cause the inelastic balloon to be pressurized to a pressure of 10
to 15 atmospheres to compress the stenosis 621. Prior to or during
this procedure it may be desirable to introduce a saline or heparin
solution or a radiopaque contrast liquid into the working space
636. This can be accomplished by introducing this liquid through
the injection lumen 502. If desired, this can be accomplished prior
to terminating the aspiration procedure hereinbefore described.
Also it should be appreciated that if desired a small endoscope can
be inserted through one of the lumens to view the area within the
working space. Alternatively, if desired an ultrasonic probe can be
utilized to view the area in which the lesion is disposed.
[0167] As hereinbefore described with a previous embodiment, in
place of the therapeutic balloon catheter, other types of catheters
can be utilized as for example one incorporating an atherectomy
device of the type hereinbefore described to facilitate removal of
the stenosis. It is readily apparent that during these procedures
if it is necessary to supply a saline solution or a heparinized
solution into the working space that the working space can also be
continued to be aspirated to remove any debris or emboli which
occur during the procedure.
[0168] Let it be assumed that the desired therapeutic actions have
been undertaken and that the stenosis 621 has been reduced and
substantially eliminated so that there is adequate flow through the
internal carotid. If it can be seen that there also is a stenosis
in the external carotid, the balloon-on-a-wire catheter 497 and the
perfusion catheter 493 can be withdrawn and moved so that they
enter the opposite carotid to permit therapeutic treatment of a
stenosis occurring in the other carotid.
[0169] When all the desired therapeutic procedures have been
accomplished, the supply of saline or contrast solution can be
terminated and the therapeutic balloon 524 deflated. The balloon
534 of the balloon-on-a-wire catheter can be deflated as well as
the perfusion balloon 509. Perfusion of blood through the perfusion
catheter can be terminated. The perfusion balloon catheter 493 and
the balloon-on-a-wire catheter 497 can be retracted into the main
multi-lumen tubular member 477 of the proximal occlusion balloon
catheter after which the perfusion balloon catheter can be
withdrawn carrying with it the other catheters disposed therein.
Thereafter, the guiding catheter can be removed and a suture
applied to the incision made to gain access to the femoral
artery.
[0170] It is readily apparent that similar procedures can be
carried out with respect to other vessels in the body, such as
saphenous vein grafts in the heart, and particularly with respect
to vessels in the brain where it is difficult if not impossible to
employ surgical procedures as for example with respect to the
basilar arteries in which bifurcations appear.
[0171] As also herein before explained, the catheter apparatus of
the present invention can be utilized for deploying stents. Where
that is desirable the apparatus of the present invention, perfusion
can be accomplished during employment of the stent.
[0172] From the foregoing it can be seen that an apparatus and
method has been provided for treating occluded vessels and
particularly for treating carotid arteries. The apparatus and
method of the present invention is particularly advantageous for
the carotid arteries because it permits access to portions of the
carotid arteries which are not accessible by surgery.
[0173] The catheter apparatus assembly and method of the present
invention are also particularly useful for treating other occluded
vessels but particularly the carotid arteries because it makes
possible the removal of plaque without endangering the patient. An
operating or working space is provided while shunting blood around
the working space so that there is continued blood flow in the
vessel to support the functions which are normally supported by the
vessel. As also pointed out above, the apparatus and method of the
present invention are particularly useful in connection with
vessels having bifurcations therein and in which the stenosis
occurs at or near the bifurcation. From the foregoing it can be
seen with the apparatus and method of the present invention,
retrograde flow of blood is accomplished during deployment of the
device to prevent undesired travel of emboli. Occlusion of the
vessels is provided to obtain a working space by bracketing the
working space with balloons while at the same time maintaining
perfusion of blood making it possible to utilize a substantial
period of time for undertaking therapeutic procedures with respect
to the bracketed stenosis.
[0174] In connection with the present apparatus and method for
treating occluded vessels, it has been found that it is possible to
utilize the apparatus and method without perfusion and other
procedures involving the carotid arteries and saphenous vein grafts
for periods of time extending over five minutes and greater which
has made it possible to simplify the apparatus and the method
utilized in conjunction therewith.
[0175] With respect to an apparatus or assembly which does not
require the use of perfusion, a main catheter 651 utilized as a
part of the apparatus is shown in FIGS. 26, 27, 28 and 29 consists
of a flexible elongate tubular member 652 formed of a suitable
material such as plastic of the type hereinbefore described and
which has proximal and distal extremities 653 and 654. The tubular
flexible elongate tubular member 652 can be of various sizes as for
example for a saphenous vein graft catheter it can be 8 to 9.5
French in balloon profile with a length ranging from 80 cm to 120
cm. The flexible elongate tubular member 652 can be formed of a
suitable material such as PEBAX, Nylon, Hytrel, polyurethane or
polyethylene. A flexible braid 656 (see FIGS. 27, 28 and 29) formed
of a suitable material such as stainless steel is embedded within
the wall of the flexible elongate tubular member 652 as shown and
extends from the proximal extremity 653 to the distal extremity
654. The braid 656 can be formed of a suitable stainless steel such
as a wire or ribbon having a thickness of 0.001". The braid 656
provides additional torquability and also inhibits the kinking of
the flexible elongate tubular member 652 when it must extend over a
tight radius. The flexible elongate tubular member 652 is provided
with a large central lumen 657 having a suitable diameter such as
0.065 or greater" extending from the proximal extremity to the
distal extremity.
[0176] If it is desired to provide a flexible elongate member 652
which has a greater flexibility at the distal extremity, a
different material can be used in the distal extremity 654. For
example, the distalmost 5-15 centimeters can be formed of a
material such as PEBAX having a Shore D hardness of 35-50 with the
remainder of the flexible elongate member 652 having a Shore D
hardness of 65-75.
[0177] A supplemental flexible elongate tubular member 661 is
provided which has incorporated therein a balloon inflation lumen
662. The supplemental flexible elongate tubular member 661 can be
of a suitable size as for example an I.D. of 0.014" and an O.D. of
0.018" and formed of a suitable material such as a polyimide. The
supplemental flexible elongate tubular member has a length which is
almost as long as the flexible elongate tubular member 652 and
overlies the outside wall of the flexible elongate tubular member
652 and extends from the proximal extremity to near the distal
extremity as shown in FIGS. 26 and 29. A tube 663 of a suitable
material such as Pebax extends over the length of the polyimide
tubing 661 and is secured to the flexible elongate tubular member
652 by a shrink tube 666 extending from the proximal extremity 653
to the distal extremity 654, after which the shrink tube 663 is
subjected to heat. The shrink tube 666 is then subjected to a hot
melt process of a temperature around 350.degree. F. for a period of
time until the Pebax tube 663 melts, after which the shrink tubing
666 can be stripped off so that there remains a relatively uniform
mass formed of Pebax that surrounds the braid 657 and the polyimide
tube 661 which forms the supplemental flexible elongate tubular
member 661. The polyimide tube which forms the supplemental
flexible elongate tubular member 661 thus provides an inflation
lumen 667 extending from the proximal extremity and to the distal
extremity and opens through an opening 668 into the interior of an
occlusion balloon 669 which is bonded to and coaxially mounted on
the distal extremity of the flexible elongate member 652 in the
manner shown in FIG. 29. The polyimide tubing is provided to give
the balloon inflation lumen shaft 361 greater strength than that
which is provided by the Pebax itself.
[0178] As can be seen from FIG. 29, the supplemental flexible
elongate tubular member 661 is terminated short of the distalmost
extremity of the flexible elongate tubular member 652 by
approximately 1 cm. The occlusion balloon 669 is formed of various
compliant or non-compliant materials. Suitable compliant materials
include elastomers such as C-Flex latex, silicones and
polyurethanes. Suitable non-compliant materials would be
polyethylene, PET and Nylon. A composite material can also be used
such as a combination of PET and an elastomer. The occlusion
balloon 669 should have a strength so that it can readily
accommodate any pressure of one atmosphere and as high as four
atmospheres, or approximately 60 psi. The occlusion balloon 669 is
cylindrical and is provided with proximal and distal extremities
671 and 672 which are secured by a suitable medical grade adhesive.
Alternatively, fuse bonding may be used. Thus a seal 673 formed of
this adhesive bonds the proximal extremity 671 of the occlusion
balloon 669 over the outer surface of the distal extremity of the
flexible elongate tubular member 652 and the supplemental flexible
elongate tubular member 661. Similarly, a seal 674 bonds the distal
extremity 672 to the distal extremity of the flexible elongate
tubular member 652 to provide an air-tight space within the balloon
accessible through the opening 668. A soft cylindrical tip 676
formed of suitable material such as Pebax is bonded to the distal
extremity of the flexible elongate tubular member 652 and is
provided with a rounded surface 677 which extends forwardly and has
a passage 678 therein in communication with the lumen 657 and the
flexible elongate tubular member 652. A cylindrical radiopaque
marker 681 formed of a suitable material such as platinum,
platinum-iridium or gold is mounted on the distal extremity of the
flexible elongate tubular member 652 in a position so it is
substantially equidistant of the ends of the occlusion balloon
669.
[0179] A main adapter or fitting 686 formed of a suitable material
such as plastic is mounted on the proximal extremity 653 of the
flexible elongate tubular member 652. It is provided with a first
Luer fitting 687 which provides a balloon inflation port 688 in
communication with the balloon inflation lumen 662. It is also
provided with another Luer fitting 689 which is provided with an
aspiration port 691 in communication with the main central lumen
657. The main adapter 686 is also provided with a Tuohy-Borst
fitting 692 which is in communication with the central lumen 657.
The Tuohy-Borst fitting 692 is adapted to receive therapeutic
devices, as for example a balloon-on-a-wire device as hereinafter
described and is adapted to form a liquid-tight seal therewith by
an o-ring 693.
[0180] A balloon-on-a-wire device 701 incorporating the present
invention is shown in FIGS. 30 and 31. The device 701 consists of a
guide wire 702 formed of a suitable material such as stainless
steel and having a suitable diameter as for example ranging from
0.010" to 0.032" but preferably a diameter ranging from 0.014" to
0.018". It is preferable that the guide wire 702 be formed of a
nickel titanium alloy typically called Nitinol which has the
advantage that it is more flexible and has greater kink resistance
characteristics than another suitable material such as stainless
steel.
[0181] It has a suitable length as for example 150 cm. The guide
wire 702 is provided with proximal and distal extremities 703 and
704 and is provided with a central lumen 706 extending from the
proximal extremity to the distal extremity. The lumen can be of a
suitable size as for example 0.010" I.D. for an 0.014" O.D. guide
wire.
[0182] An occlusion balloon 711 is coaxially mounted on the distal
extremity 704 of the guide wire 702. The occlusion balloon 711 is
preferably formed of the same material as the occlusion balloon 669
on the main catheter 651. The occlusion balloon 711 has proximal
and distal extremities 712 and 713. A tube 716 formed of a suitable
material such as a polyimide is disposed within the occlusion
balloon 711 and has a bore 717 extending therethrough which is
sized so that it is slightly larger than the outside diameter of
the guide wire 702 so that its proximal extremity can be slipped
over the distal extremity 704 of the guide wire 702 and then bonded
thereto by suitable means such as an adhesive 718. A plurality of
circumferentially spaced apart radially extending inflation holes
719 are provided in the proximal extremity of the tube 716 and are
in alignment with similarly spaced holes 721 provided in the distal
extremity 704 of the guide wire 702 so that they are in
communication with the central lumen 706 of the guide wire 702. The
inflation holes 719 as shown are in communication with the interior
of the occlusion balloon 711 so that fluid passing from the passage
706 can be utilized for inflating the occlusion balloon 711.
[0183] A solid core wire 723 formed of a suitable material such as
stainless steel is provided with a proximal tapered extremity 724.
The core wire 723 is sized so it is adapted to fit within the lumen
706 of the guide wire 702 and is secured therein by suitable means
such as an adhesive 726 or alternatively a weld. The core wire 723
has a tapered portion 723a which commences at the proximal
extremity 724 and which is tapered so that the cross-sectional
diameter progressively decreases to the distal extremity of the
occlusion balloon 711. The core wire 723 is also provided with
additional portions 723b and 723c which can be of substantially
constant diameter as for example 0.003". The portion 723 is folded
over with respect to the portion 723b so that the portions 723b and
723c lie in a plane to facilitate shaping of the distal extremity
of the guide wire 702 during use of the same. The core wire 723 is
provided with a distal extremity 727 in which a bend 728 is formed
between the two portions 723b and 723c. The bend 728 is secured
within a hemispherical solder bump or protrusion 729 which is
carried by the distal extremity of a coil 731 formed of a suitable
radiopaque material such as platinum or a platinum alloy. The
platinum coil 731 can have a suitable outside diameter as for
example 0.014" corresponding to the diameter of the guide wire 702
and can have a suitable length ranging from 1 to 3 cm. The proximal
extremity of the coil 731 is secured to the distal extremity of the
polyimide tube 716 by suitable means such as an adhesive 732 which
can be the same adhesive or a different adhesive 733 utilized for
securing the distal extremity 713 of the balloon to the polyimide
tube 716 to form a fluid-tight seal between the distal extremity of
the occlusion balloon 711 and the distal extremity of the polyimide
716. From this construction it can be seen that the portions 723b
and 723c of the core wire 723 in addition to serving as a shaping
ribbon are also utilized as a safety ribbon to ensure that the tip
728 and the spring 731 cannot be separated from the guide wire 702.
The proximal extremity 712 of the balloon 711 is also secured to
the proximal extremity of the polyimide tube 716 and also to the
distal extremity 704 of the guide wire 702 to form a fluid-tight
seal with respect to the occlusion balloon 711 so that the
occlusion balloon 711 can be inflated and deflated through the
inflation holes 719 and 721.
[0184] Alternative constructions for the distal extremity of the
core wire 723 are shown in FIGS. 33 and 34. In FIG. 23 it can be
seen that the portions 723b and 723c have been twisted to in effect
provide a twisted pair serving as a safety ribbon and as a shaping
ribbon. In the embodiment shown in FIG. 34, the core wire 736 is
provided with a tapered portion 736a which is the same as the
tapered portions of 723a hereinbefore described. However, the core
wire 736 has been provided with a distal portion 736b which has
been flattened to a suitable thickness as for example a width of
0.006" and a thickness of 0.003" and then twisted to form a helix
as shown in which the distal extremity is embedded within the
solder 729. Such a helix 736 can serve as a safety ribbon and also
can be shaped to some extent.
[0185] A removable inflation fitting 741 or valve attachment 741 is
mounted on the proximal extremity of the guide wire 702 and forms a
part of the balloon-on-a-wire device 701. The fitting or attachment
741 is formed of a suitable material such as a polycarbonate and is
provided with a central bore 742. The attachment or fitting is slid
externally over the proximal extremity 703 of the guide wire 702.
Means is provided for forming a fluid-tight seal between the
proximal extremity 703 of the guide wire 702 and a body 743 of the
fitting 741 and consists of an o-ring 746 (see FIG. 35) seated in a
well 747. A thumb screw 748 is threadedly mounted on the body 743
and is provided with an inwardly extending circular protrusion 749
that is adapted to engage the o-ring 746 and to compress the same
to form a fluid-tight seal when the protrusion 749 is moved
inwardly toward the o-ring 746 as the thumb screw 748 is rotated in
a clockwise direction. The o-ring 746 decompresses or springs back
when released upon rotation of the thumb screw 748 in a
counterclockwise direction so that the fitting 741 can be removed
from the distal extremity 703 of the guide wire 702. The body 742
also includes a Luer fitting 751 which provides an inflation port
752 that is in communication with the bore 742 in the body 743 and
which is also in communication with the open proximal extremity of
the guide wire 702 and the lumen 706 therein.
[0186] Means is provided for plugging the bore 706 when the
removable attachment or fitting 741 is removed and consists of a
plug mandrel 756 formed of a suitable material such as 0.014"
stainless steel solid rod. It is necessary that this rod have a
diameter which is greater than the diameter of the lumen 706 and
the guide wire 702. The plug mandrel 756 is provided with a
progressive portion 756a that tapers down from as, for example from
0.014" to a suitable diameter as for example 0.008" to a
cylindrical portion 756b.
[0187] Means is provided for forming a fluid-tight seal between the
plug mandrel 756 which forms a plug mandrel and the body 743 of the
attachment or fitting 741 and consists of an o-ring 766 providing
suitable sealing means seated within a well 762 provided in the
body 743. A thumb screw 763 threadedly engages the body 743 and is
provided with a cylindrical protrusion 764 which engages the o-ring
and compresses it to form a fluid-tight seal with respect to the
plug mandrel 756 by rotation in a clockwise direction of the thumb
screw 763. The plug mandrel 756 can be released by a
counterclockwise rotation of the thumb screw 763 permitting
decompression of the o-ring 761.
[0188] An irrigation catheter 766 incorporating the present
invention is shown in FIG. 36 and consists of a flexible elongate
tube 767 formed of a suitable material such as polyethylene, PEBAX,
Hytrel or Teflon having a suitable size as for example an outside
diameter of 0.066" and an inside diameter of 0.058" and having a
length of approximately 150 cm. A lumen 768 is provided therein and
extends from the proximal extremity to the distal extremity and is
in communication with an adapter 769 provided on the proximal
extremity of the tube 767. The adapter 769 is provided with a body
770 formed of a suitable material such as plastic and is provided
with a bore 771 extending therethrough. The adapter 769 is provided
with a side arm 772 which carries a conventional Luer-type
connection and provides an irrigation port 773 in communication
with the bore 771. A thumb screw 774 threadedly mounted on the body
770 carries a cylindrical protrusion 776 adapted to compress an
o-ring 777 carried by the body 770 into engagement with a
therapeutic catheter of the type hereinafter described. A
radiopaque tip marker 778 of a suitable type, as for example one
formed as a platinum-iridium band 778 is provided on the distal
extremity of the flexible elongate element 767 to facilitate
positioning of the irrigation catheter as hereinafter
described.
[0189] Operation of the apparatus shown in FIGS. 26 through 36 in
performing the method of the present invention for treating
occluded vessels may now be briefly described as follows utilizing
the cartoons which are shown in FIGS. 37-43. Let it be assumed that
it is desired to treat a vessel 781 in the human body as for
example a saphenous vein graft having at least a partial occlusion
or stenosis 782 which is formed by plaque in the vessel. The main
catheter 651 is introduced into the body through a conventional
procedure such as for example by making an incision into the
femoral artery in a leg of the patient.
[0190] Thereafter the main catheter 651 can be introduced into the
femoral artery by use of a large conventional guiding catheter
because the main catheter 651 is of a relatively large size, as for
example 8 to 9.5 French. In order to eliminate the need for such a
large guiding catheter, a smaller conventional guiding catheter 786
of the type shown in FIG. 37 can be utilized which can be
introduced through the main catheter 651. Utilizing such a
catheter, the main catheter 651 can be inserted independently
through a conventional sheath (not shown) in the femoral artery and
thereafter the guiding catheter 786 is introduced through the main
catheter 651 so that its distal extremity 789 is in the vessel.
Alternatively, the guiding catheter 786 can be deployed into the
main catheter 651 and the guiding catheter 786 introduced at the
same time into the femoral artery.
[0191] The guiding catheter 786 is conventional and thus will not
be described in detail. It consists of a flexible elongate tubular
member 787 (see FIG. 37) formed of a suitable material such as
plastic having proximal and distal extremities 788 and 789. The
distal extremity 789 is provided with a preformed bend as shown. An
adapter 792 is mounted on the proximal extremity 788 and consists
of a body 793 in the form a wye in which the central leg 794 is
provided with a flow passage (not shown) therein in communication
with the central lumen (not shown) extending from the proximal
extremity 788 to the distal extremity 789 of the flexible elongate
tubular member 787. The body 793 is provided with a side leg 796
which also is in communication with a lumen (not shown) extending
from the proximal extremity 788 to the distal extremity 789. A knob
797 carrying an o-ring (not shown) secures the adapter 792 to the
proximal extremity 788 with a fluid-tight seal. Another knob 798 is
provided which is carried by the central leg 794 of the body 793
and is provided with an o-ring (not shown) which can be moved to
close the flow passage in the central leg 794, or alternatively it
can be opened to receive a guide wire which can be utilized for
advancing the guide catheter 786 if that be necessary and then
forming a fluid-tight seal with respect to the guide wire.
[0192] Assuming that the guiding catheter 786 has been inserted
into the main catheter 651 before insertion of the main catheter
651 into the femoral artery, both catheters can be inserted in
unison while advancing the distal extremity of the guide catheter
786 so that it precedes the distal extremity of the main catheter
651 and serves to guide the main catheter 651 into the vessel of
interest, as for example the vessel 781 having the stenosis 782
therein. The main catheter 651 is then advanced so that its distal
extremity is at the proximal side of the stenosis 782. By way of
example, the main catheter 651 can be advanced through the aortic
arch of the heart and thence into a saphenous vein graft so that
the occlusion balloon 669 on its distal extremity is positioned
proximal of the stenosis 782. As soon as this has been
accomplished, the guiding catheter 786 can be removed.
[0193] As soon as the distal extremity of the main catheter 651 has
been deployed so that it is just proximal of the stenosis 782 to be
treated, an assembly shown in FIG. 38 is introduced into the main
catheter 651. This assembly can be provided by preloading the
irrigation catheter 766 onto the therapeutic catheter 801 by
inserting the distal tip of the therapeutic catheter 801 through
the fitting 769 of the irrigation catheter 766 and advancing the
therapeutic catheter 801 until its therapeutic balloon 809 exits
from the irrigation catheter 766. The balloon-on-a-wire catheter
701 also is preloaded by removing the valve attachment 746 and then
inserting the proximal end 703 into the guide wire lumen at the
distal tip of the therapeutic catheter 801 and then advanced
proximally until the proximal end protrudes out of the proximal end
of the therapeutic catheter. The valve attachment 741 is then
reattached to the proximal end 703. The preassembled irrigation
catheter 766, the therapeutic catheter 801 and the
balloon-on-a-wire catheter 701 are then introduced in unison as an
assembly into the main catheter 651. The balloon-on-a-wire device
701 is then advanced until the distal extremity is near the distal
extremity of the main catheter 651 but before the distal extremity
has been advanced through the stenosis 782.
[0194] Let it be assumed that it is now desired to inflate the
occlusion balloon 669 carried by the main catheter 651. This can be
accomplished in a suitable manner such as with an
inflation-deflation device represented schematically by a syringe
802 secured to the fitting 687 (see FIG. 38) and supplying a
balloon inflation fluid through the balloon inflation lumen 662 to
inflate the occlusion balloon 669 to an occlusion pressure ranging
from 1 to 3.9 atmospheres and preferably approximately one to two
atmospheres to engage the side wall forming the vessel 781 to
occlude the vessel 781 and to prevent further blood flow through
the vessel and to thereby provide a working space 803 distal of the
occlusion balloon 669. As soon as the occlusion balloon 669 has
been inflated, the balloon-on-a-wire device 701 can be advanced
across the lesion or stenosis 782 until the deflated occlusion
balloon 711 carried thereby is distal of the stenosis 782. It is
safe to cross the stenosis 782 because the flow of blood through
the stenosis 782 has been occluded by the occlusion balloon 669.
Thus if any of the plaque forming the stenosis is dislodged by the
occlusion balloon 711 on the balloon-on-a-wire device 701 as the
occlusion balloon 711 is crossing the stenosis 782, the plaque
particles or emboli 804 will not be carried off by blood. The
positive pressure of blood in secondary collaterals or vasculature
will prevent emboli from traveling downstream into the secondary
vasculature. If desired, aspiration can be supplied to the working
space 803 encompassing the stenosis 782 by placing a suitable
vacuum connected to the fitting 689 of the main catheter.
[0195] The occlusion balloon 711 can then be readily inflated by
use of a syringe 805 secured to the fitting 751 of the removable
valve fitting or attachment 741 of the balloon-on-a-wire device 701
proximal of the fitting 686 and accessible outside the body of the
patient. The occlusion balloon 711 is inflated (see FIG. 39) to at
least approximately one to two atmospheres to bracket the stenosis
and to determine the size of the working space 803 to provide a
chamber. It should be appreciated that the size of this working
space or chamber 803 can be adjusted by changing the position of
the occlusion balloon 711 in the vessel 781. If desired, this can
be accomplished while the occlusion balloon 711 is inflated.
[0196] Now let it be assumed that the occlusion balloon 711 has
been inflated with the appropriate working space 803 and that it is
desired to introduce a therapeutic balloon catheter 801 into the
working space 803 to treat the stenosis 782. If the therapeutic
catheter 801 is not in the main catheter 651 as hereinbefore
described, this can be readily accomplished in the present
invention by inserting a plug mandrel 756 into the open end of the
lumen 706 of the guide wire 702. After the plug mandrel 756 has
been inserted, the syringe 805 can be removed after which the thumb
screws 748 and 763 can be loosened to permit the o-rings therein to
become decompressed and to release the guide wire 702 and the plug
mandrel 756 to permit the fitting or valve attachment 741 to be
slipped off to provide a proximal end on the guide wire 702 which
is free of obstructions. During removal of the valve attachment or
fitting 741, the occlusion balloon 711 remains inflated and
continues to be disposed distally of the stenosis 782. The
occlusion balloon 669 also remains inflated because the syringe 802
remains attached to the fitting 686 and is disposed proximal of the
stenosis 782.
[0197] The conventional therapeutic catheter 801 then can be
delivered over the guide wire 702 if it is not already present. The
therapeutic catheter 801 is provided with a flexible elongate
tubular member 806 having proximal and distal extremities 807 and
808 with a central flow passage (not shown) extending between the
same. A therapeutic balloon 809 on its distal extremity is adapted
to be inflated to therapeutic pressures ranging from 4-20
atmospheres through a balloon inflation lumen (not shown) carried
by the flexible elongate tubular member 806 through an adapter 811
mounted on the proximal extremity 807. The therapeutic balloon 809
can be considered to be means for performing work carried by the
distal extremity 808 of the flexible elongate tubular member 806.
The adapter 811 can be removable of the type hereinbefore described
or alternatively can be permanently attached thereto. Assuming that
it is a removable adapter, the removable adapter 811 is provided
with knobs 812 and 813 carrying o-rings (not shown) adapted to
establish fluid-tight seals with the flexible elongate member 806
and the plug mandrel 756, respectively. It is also provided with an
inflation port 816 similar to those hereinbefore described which is
in communication with the inflation lumen (not shown) provided in
the flexible elongate tubular member 806 for inflating the
therapeutic balloon 809.
[0198] After the balloon catheter 801 has been positioned by the
use of radiopaque markers (not shown) conventionally employed in
such devices, the therapeutic balloon 809 is disposed so that it is
in general alignment with the stenosis 782 as shown in FIG. 39. The
therapeutic balloon 809 is then inflated in a conventional manner
to perform work by use of an inflation-deflation device
schematically represented by the syringe 817 attached to the
inflation port 816 to the desired pressure to compress the plaque
forming the stenosis 782 as shown in FIG. 40 to increase the size
of the opening through the stenosis 782 in the vessel 781.
[0199] Let it be assumed that during the compression of the plaque
forming the stenosis 782, additional emboli 804 are formed as shown
in FIG. 41 by pieces of plaque becoming dislodged from the plaque
782 within the vessel 781. Let it also be assumed that it is
desired to remove these emboli before deflation of the occlusion
balloons 669 and 711 disposed proximally and distally of the
stenosis 782. To accomplish this, the therapeutic balloon 809 is
deflated by use of the syringe 817. As soon as this has been
accomplished, a saline solution can be introduced through the
irrigation catheter 766 by connecting a tube 819 carrying the
saline solution from a suitable source as for example a free or
pressurized saline bag (not shown) and delivered through the
irrigation port or side arm 772 where it is carried through the
large central lumen of the irrigation catheter 766 so that the
saline solution is discharged into the working space 803 disposed
between the occlusion balloons 711 and 669 as shown in FIG. 41. At
the same time suitable aspiration means is connected to the
aspiration port 689 of the adapter 686 and as shown can consist of
a hand operated bulb 821 which has a one way check valve 822
therein connected to the fitting 689.
[0200] The bulb 821 is provided with another one-way check valve
823 which is connected to a flexible collection bag 824. The bulb
821 makes it possible to generate a vacuum corresponding
approximately to 3-30" of mercury. Thus, by compressing the bulb
821 by hand, it is possible to create suction within the chamber or
space 803 formed in the vessel between the occlusion balloons 669
and 711 each time the bulb 821 is compressed and released.
Alternatively, the aspiration can be accomplished by use of a
syringe in place of the bulb 821 and the collection bag 824. Saline
liquid supplied through the irrigation catheter 766 carrying the
emboli 818 is aspirated through the central lumen 657 of the main
catheter 651. The aspirated liquid in each cycle of operation
created by pressing the bulb 821 is delivered to the collection bag
824. With such a procedure it has been found that it is possible to
aspirate emboli as large as 600 .mu.m. Such removal can be assured
by observing when clear liquid exits outside the body from the
aspiration port 691. A chamber having a length ranging from 3 cm to
15 cm can be totally cleared of emboli within a short period of
time ranging from 5 to 30 seconds. Alternatively, irrigation can be
accomplished by removing the therapeutic catheter 801 after
deflating the therapeutic balloon 809. The irrigation catheter can
be advanced over the balloon-on-a-wire device 701 until the distal
tip is just proximal of the occlusion balloon 711 as shown in FIG.
42 to provide a greater flow of saline and faster aspiration.
[0201] After all of the emboli 804 have been removed, introduction
of saline through the tube 819 is halted. It should be appreciated
that the ports for irrigation and aspiration can be reversed in
function if desired. Thereafter, the occlusion balloon 711 is
deflated by removing the plug 756 and utilizing a syringe 805,
after which the occlusion balloon 669 is deflated permitting blood
flow to be reestablished in the vessel 781. Alternatively, the
occlusion balloon 669 can be first deflated and aspiration
commenced at that time, permitting emboli trapped distally of the
occlusion balloon 669 by blood flowing from the proximal side of
the occlusion balloon 669 to be aspirated through the central lumen
657. In order to prevent excessive expansion of the vessel 781
being treated, the pressure of the irrigation liquid is typically
maintained under 30 psi. This pressure preferably should be below
the occlusion balloon pressure.
[0202] If it is desired to deliver a stent to the site of the
stenosis formed by the plaque 782, this can be readily accomplished
during the same procedure. Typically it is desirable to permit the
blood to flow normally for a period of several minutes after which
the occlusion balloon 669 can be reinflated by the syringe 805 and
the occlusion balloon 711 can be reinflated by inserting the
removable valve attachment 741 if it has been removed of the
balloon-on-a-wire device 701 and utilizing the syringe 803 to
reinflate the occlusion balloon 711. The plug mandrel 756 can be
inserted to keep the occlusion balloon 711 inflated after which the
valve attachment 741 can be removed.
[0203] A conventional stent delivery catheter 826 carrying a stent
827 on its flexible shaft 828 is introduced over the
balloon-on-a-wire device 701 and delivered to the site of the
dilated stenosis 782 (see FIG. 43). The stent 827 can be of the
self-expanding type or of the type which can be expanded by a
balloon (not shown) carried by the catheter 826 by connecting a
syringe 829 to an adapter 830 of the type hereinbefore described of
the stent delivery catheter 826. After the stent 827 has been
deployed in the dilated stenosis 782, the stent delivery catheter
826 can be removed after which the occlusion balloon 711 can be
deflated followed by deflation of the proximal balloon 661 in the
manner hereinbefore described. Also it should be appreciated that
if desired in connection with the deployment of the stent delivery
catheter 826 before it is removed but after deflation of its
balloon (not shown), it may be desirable to again flush the working
space or chamber 803 between the occlusion balloons 669 and 711 of
emboli which may be dislodged during the delivery and deployment of
the stent. The irrigation catheter 766 can be deployed in the same
manner as hereinbefore described with a saline irrigation solution
supplied to the working space 803 in the manner hereinbefore
described and liquid aspirated therefrom by the use of the bulb 821
in the manner hereinbefore described.
[0204] Heretofore the apparatus of the present invention has been
utilized for performing a procedure on a saphenous vein graft where
there are no branches to be dealt with. An apparatus incorporating
the present invention also can be useful in connection with vessels
in a human being having branches therein, as for example the
carotids. For this purpose, a main catheter 831 (see FIG. 44) is
provided which is very similar to the main catheter 651 with the
exception that the adapter 832 provided on the proximal extremity
is provided with catheter ports 833 and 834 which are in
communication with the large central lumen 657 extending the length
of the main catheter. The catheter ports 833 and 834 have a
construction similar to the exchange catheter and therapeutic
catheter port 692 hereinbefore described in connection with the
main catheter 651. These two catheter ports 833 and 834 are
necessary because in a carotid procedure, two balloon-on-a-wire
devices are utilized. The main catheter should be larger, as for
example as large as 12 French, to provide a larger central lumen to
accommodate the two balloon-on-a-wire devices.
[0205] One of the balloon-on-a-wire devices can be substantially
identical to the balloon-on-a-wire device 701 described. The other
balloon-on-a-wire device 835 as shown in FIG. 45 differs from the
device 701 shown in FIG. 30 in that in place of the removable valve
attachment 741 there is provided a fixed adapter 836 which consists
of a body 837 provided with diametrically extending wings 838 to
facilitate grasping of the adapter 836. The body 837 is provided
with a bore 839 which is in communication with the lumen 706 in the
guide wire 702. The adapter is provided with a Luer-type fitting
840 to provide a balloon inflation port.
[0206] Operation and use of the apparatus of the present invention
in performing a procedure in a carotid artery is shown in the
cartoons in FIGS. 46-50. Let it be assumed that it is desired to
perform a procedure with the apparatus of the present invention on
a carotid artery in a patient, as for example common carotid 841
which branches into an external carotid 842 and an internal carotid
843 and that there is a narrowing or a stenosis 844 in the internal
carotid 843 near the bifurcation into the external and internal
carotids 842 and 843. The main catheter 831 can be introduced in
the manner hereinbefore described with respect to a saphenous vein
graft. For example it can be introduced through the femoral artery
in the leg and then advanced into the aortic arch up into the
common carotid 841 until the occlusion balloon 669 carried thereby
is near the bifurcation as shown in FIG. 46. The occlusion balloon
669 is then inflated to at least one atmosphere as shown in FIG. 47
to form a seal to occlude the common carotid 841 and to temporarily
stop the flow of blood to the face and brain of the patient through
the common carotid 841 and to provide a working space 845 distal of
the occlusion balloon 669. The inflation is accomplished by
suitable means as for example a syringe 846 secured to the balloon
inflation fitting 687. Thereafter, a balloon-on-a-wire device 831
of the type shown in FIG. 45 is introduced through the catheter
port 833 and advanced through the central lumen 657 of the main
catheter 831 after which the distal extremity is guided into the
external carotid 842 so it is disposed beyond the bifurcation. The
occlusion balloon 711 carried by the distal extremity is then
inflated by suitable means such as a syringe 847 secured to the
attachment 836 to occlude the external carotid. As hereinbefore
pointed out, the balloon 711 is an occlusion balloon that typically
is inflated to a suitable occlusion pressure as for example one to
two atmospheres.
[0207] Another balloon-on-a-wire device such as the
balloon-on-a-wire device 701 is then introduced through the
catheter port 834 and advanced through the central passage or lumen
657 until it exits from the main catheter 831 after which it is
guided into the internal carotid 843 past the stenosis 844 so that
the occlusion balloon 711 is distal of the stenosis 844. The
occlusion balloon 711 is then inflated as shown by the dotted lines
in FIG. 47 by the use of a syringe 848 secured to the inflation
port carried by the removable valve attachment 741. Thus, the
limits of the working space or chamber 845 are defined by the
occlusion balloons 669 and 711. As soon as the balloon 711 has been
inflated, the balloon inflation lumen can be plugged in the manner
hereinbefore described by the use of a plug mandrel 756 (see FIG.
48). It should be appreciated even though the guide wire 702 and
the occlusion balloon 711 carried thereby may dislodge particles
from the plaque forming the stenosis 844, the dislodged particles
will not travel to the brain because the common carotid supplying
blood to the internal carotid 843 has been occluded by the
occlusion balloon 669.
[0208] The removable valve attachment 741 can then be removed in
the manner hereinbefore described so that the proximal extremity of
the guide wire 702 is free of obstructions as shown in FIG. 68.
Thereafter the irrigation catheter 766 can be introduced over the
guide wire 702 and thence into the port 834 until its distal
extremity extends beyond the distal extremity of the main catheter
831. A therapeutic balloon catheter 801 of the same type as
hereinbefore described can then be introduced through the
irrigation catheter 766. It should be appreciated that if desired,
the therapeutic balloon catheter can be preloaded into the
irrigation catheter 766 and the irrigation catheter 766 and the
therapeutic balloon catheter 801 can be introduced in unison.
Assuming that the irrigation catheter 766 has been introduced
first, the therapeutic balloon catheter 801 is introduced through
the irrigation catheter 766 until it extends beyond the distal
extremity of the irrigation catheter 766 and is moved into the
working space 845 until the therapeutic balloon 809 carried by the
distal extremity thereof is in registration with the stenosis 844.
The therapeutic balloon 809 is then inflated as shown in FIG. 48 by
the use of an inflation/deflation device 851 represented
schematically by a syringe to a suitable therapeutic pressure to
compress the plaque forming the stenosis 844 to dilate the stenosis
to increase the size of the flow passage through the stenosis 844.
The therapeutic balloon 809 can then be deflated. In the event
emboli 804 are created as hereinbefore described by the passage of
the therapeutic balloon 809 through the stenosis, these emboli 804
can be removed as shown in FIG. 49 by introducing a saline solution
through the tube 819 and into the irrigation port 773 of the
irrigation catheter 766 to cause a saline solution to be discharged
into the space formed between the two occlusion balloons 711 and
669. To achieve a more effective aspiration, the distal tip of the
irrigation catheter 766 can be moved through the stenosis 844 to
just proximal of the occlusion balloon 711. Aspirate is removed
through the aspiration port 689 through the use of the bulb 821 and
the collection bag 824 to remove the saline solution carrying with
it the emboli 804 which may have been created and deposit the same
in the collection bag 824. This irrigation and aspiration can be
carried on for a suitable period of time as for example 5 to 30
seconds after which the occlusion balloons 711 in both of the
branches 842 and 843 can be deflated and the devices 701 and 835
can be removed along with the catheter 801 carrying the therapeutic
balloon 809. Similarly, the occlusion balloon 669 can be deflated
to permit blood to flow into the common carotid 841 and the
external and internal carotids 842 and 843. Alternatively, the
sequence of deflation of the balloons can be carried out in the
manner hereinbefore described in connection with a vessel without a
bifurcation.
[0209] In the event it is desired to deliver a stent into the
dilated stenosis 844, this can be accomplished by reinflating the
occlusion balloon 669 and then reinflating the occlusion balloons
711 in both of the branches after which a balloon stent delivery
catheter 826 of the type hereinbefore described can be delivered
over the guide wire 702 in the same manner as the therapeutic
balloon catheter 766 and delivered into the desired location and
then deployed in the dilated stenosis 844. After the stent 827 has
been deposited and the balloon of the stent delivery catheter 826
is deflated, the irrigation and aspiration procedures hereinbefore
described can be repeated to remove any emboli within the space
formed between the occlusion balloons 711 and 669. The stent
delivery catheter 826 can be removed. After a suitable period of
irrigation and aspiration, as for example 5 to 30 seconds, the
occlusion balloon 711 can be deflated after which the occlusion
balloon 669 can be deflated and the balloon-on-a-wire devices 701
and 835 removed along with the main catheter 652.
[0210] From the foregoing it can be seen that there has been
provided a new and improved apparatus and a method for utilization
of the same which makes it possible to carry out such stenosis
opening procedures without the perfusion of blood. Complete
stenosis procedures can be carried out in a period of time which is
less than six minutes for each complete procedure. Even though
blood flow is occluded during this period of time, this period of
time is much less than the period of time, as for example 30
minutes, required for a conventional endoatherectomy. Thus, the
procedures of the present invention can be carried out without
endangering the patient, as for example the brain or the heart of
the patient.
[0211] The desire to eliminate the use of a large guiding catheter
for use with the main catheter 651 was hereinbefore discussed.
Also, it was hereinbefore disclosed that the main catheter 651 can
be inserted independently through a conventional sheath (not shown)
in the femoral artery and thereafter a smaller conventional guiding
catheter 786 is introduced through the main catheter so that its
distal extremity 789 is in the vessel. In other procedures it may
be desirable to carry this concept still further, i.e., eliminating
the need for a large guiding catheter and also the need for a
smaller guiding catheter to be advanced through the main catheter.
To do this, it may be desirable to provide a distal extremity on
the main catheter 651 which is shaped in a predetermined manner.
For example, in the main catheter 651a shown in FIG. 26A there is
provided in the distal extremity a conventional Judkins left shape
and in the main catheter 651b shown in FIG. 26B there is provided
in the distal extremity a conventional Judkins right shape. Other
than the shaping of the distal extremities as hereinbefore
described, the main catheters 651a and 651b are constructed in a
manner very similar to the catheter 651 and are provided with
occlusion balloons 669 as shown.
[0212] Since the main catheters 651a and 651b are relatively
flexible, they can be inserted into the femoral artery and have
their distal extremities guided into the desired locations with the
catheter being selected for the appropriate bend to reach the
desired location. With the main catheter having such capabilities,
it is possible in connection with the present invention to advance
the main catheter 651 into the desired location by the use of a
balloon-on-a-wire device of the type hereinbefore described, or
alternatively over a conventional guide wire. This makes it
possible to eliminate the use of a guiding catheter and therefore
substantially simplify the procedures of the present invention and
reduce the costs of such procedures.
[0213] In connection with the irrigation catheter 766 hereinbefore
described in FIG. 36, it should be appreciated as shown in FIGS.
36A and 36B that irrigation catheters 766a and 766b can be provided
which have soft distal extremities to provide additional
flexibility and trackability and thereby reduce trauma in vessels
through which they are introduced. Thus in the irrigation catheter
766a shown in FIG. 36A, the main portion of the flexible elongate
tubular member 767 which can be considered to be the shaft can have
a greater stiffness than the distal portion 767a of the distal
extremity. This can be readily accomplished by utilizing a plastic
such as Pebax and Hytrel of various desired durometers. For
example, the main shaft 767 can have a durometer ranging from
80-100 whereas the distal portion 767a can have a durometer ranging
from 50-70. The cylindrical tip 767c with a rounded forward edge as
shown is provided with a still lower durometer as for example 35-55
durometer. Thus it can be seen that there has been provided an
irrigation catheter which has a very soft tip and which has a
distal portion in the distal extremity which is very flexible to
permit tracking and to reduce trauma.
[0214] In the irrigation catheter 766b shown in FIG. 36, the shaft
767 can have a durometer ranging from 80-100 whereas the portion
767a can have a durometer ranging from 60-70 and which has a
portion 767b formed of the same durometer material that is inclined
inwardly and distally to reduce the size of the opening for the
passage or lumen 768 as shown. The tip 767 which can be formed of a
low durometer as for example 35-55 durometer is mounted on the
distal extremity 767b. In order to enhance the flow of irrigation
fluid from the lumen 768 a plurality of holes 857 is
circumferentially distributed around the portion 767a to augment
the flow of irrigation fluid other than through the passage 856.
The use of the embodiments 766a and 766b of the irrigation catheter
is very similar to that hereinbefore described with the irrigation
catheter 766 shown in FIG. 36. It should be appreciated that if
differing stiffnesses are desired for the main catheters 651 and
831, the same concepts as disclosed for the irrigation catheter 766
can be utilized by selecting materials having desired durometers
for various portions of the catheters.
[0215] Another embodiment of the balloon-on-a-wire device is shown
in FIGS. 51 and 52 in which the balloon-on-a wire device 901 is in
many respects very similar to the balloon-on-a-wire device 701
shown in FIG. 30 as hereinbefore described. The balloon-on-a-wire
device 901 consists of a flexible elongate member in the form of a
guide wire 702 having proximal and distal extremities 703 and 704
with a lumen 706 extending therethrough. A removable valve
attachment or fitting 741 is provided on the proximal extremity
907. A plug mandrel 756 is carried by the removable valve
attachment 741 for use in plugging the bore 706 when necessary. An
elastomeric balloon 906 is provided on the distal extremity 704 and
is provided with proximal and distal extremities 907 and 908. The
balloon 906 has a suitable length as for example 10 millimeters and
a suitable diameter when collapsed or deflated of 1 mm. In order
that the balloon 906 assume a generally rectangular shape as viewed
in cross-section as shown in FIG. 51 with generally right angle
comers, the balloon 906 is provided with spaced-apart cylindrical
regions 906a and 906b of greater thickness than an intermediate
portion 906c. For example, portions 906a and 906b can have a
thickness of 0.006" to 0.010" and portion 906c of 0.003" wall
thickness. Such a balloon when inflated will have a squareness as
illustrated by the dotted lines in FIG. 51. This squareness of the
balloon comers helps to assure that emboli will not become
entrapped between the balloon and the vessel wall and thereby will
not roll by the balloon as it is moved in the vessel.
[0216] An elongate slot 911 is ground into the distal extremity of
the guide wire 702 to a suitable depth which is in excess of one
half of the diameter of the guide wire 702. The slot 911 is in
communication with the lumen 706 and opens into the interior of the
balloon 906. A tapered core wire 913 is mounted in the distal
extremity 704 of the guide wire 702. The core wire 913 is provided
with a portion 913a which has a progressive decrease in diameter
extending from the proximal extremity to a portion 913b which is
generally of a uniform diameter of a suitable size, as for example
0.003" and is formed into a bend 916 and extends proximally along
the slot 916 and proximally thereof where it is secured to the
guide wire 702 by suitable means such as an adhesive 918. A coil
spring 921 formed of a suitable material such as stainless steel or
platinum extends over the slot 911 and proximally and distally of
the slot 911 and is secured thereto by suitable means as solder
922. Positioned in this manner, the coil 921 generally
circumscribes the inner circumference of the balloon 906 and serves
to protect the balloon 906 from any sharp edges as for example
sharp edges formed by the slot 911 in the coil wire 702. A tip coil
926 formed of a suitable radiopaque material such as a platinum or
a platinum alloy is mounted over the distal extremity of the guide
wire 702 and secured thereto by suitable means such as solder 927.
The distal extremity of the tip coil 926 which may have a suitable
length, as for example 3 mm, is bonded to the core wire 913b by a
solder 928 which encloses the bend 916 and provides a rounded
forwardly protruding surface 929. The distal extremity 908 of the
balloon 906 is secured to the coils 921 and 926 by an adhesive 931.
Similarly, the proximal extremity 907 of the balloon 906 is secured
to the guide wire 702 and the portion 913b by an adhesive 932.
[0217] The balloon-on-a-wire device 901 can be utilized in the same
manner as the balloon-on-a-wire device 701 hereinbefore described.
It is believed that the balloon-on-a-wire device 901 has several
desirable features. For example the balloon 906 is protected from
any sharp edges by the coil spring 921. The slot 911, in addition
to providing a means for inflating the balloon, also serves to
provide a progressive weakening of the distal extremity of the
guide wire 702 to impart additional flexibility to the distal
extremity of the device.
[0218] By utilizing a balloon-on-a-wire constructions herein
disclosed, it is possible to reduce the overall size of the
apparatus for the procedures. In view of the fact that guide wires
having a size of 0.014" to 0.018" are utilized in the present
invention, many conventional therapeutic balloon devices can be
utilized by advancing the same over such size guide wires. By the
provision of removable valve attachments for the balloon-on-awire
devices, it is possible to use such devices for providing the one
or more balloons necessary for a procedure while at the same time
making it possible to utilize such devices as guide wires after
removing the removable valve attachments on the proximal
extremities. This makes it possible to utilize conventional stent
delivery catheters, ultrasound catheters and the like by advancing
them over the already in place guide wires.
[0219] It should be appreciated that it may be possible to
eliminate the use of the occlusion balloons 711 which are distal of
the proximal balloon carried by the main catheter and distal of the
stenosis, since blood flow is occluded during the time that the
occlusion balloon 669 is inflated.
[0220] Another embodiment of a catheter apparatus incorporating the
present invention for treating occluded vessels is shown in FIGS.
53 and 54. As shown therein, the catheter apparatus 951 consists of
a flexible elongate member 952 similar to those hereinbefore
described which is provided with proximal and distal extremities
953 and 954. A conventional adapter 956 is mounted on the proximal
extremity and is provided with a Tuohy-Borst fitting 957 which is
in communication with a large central lumen 958 extending from the
proximal extremity 953 to the distal extremity 954. An aspiration
fitting 961 is provided on the adapter 956 as well as an irrigation
fitting 962, both of which are in communication with the central
lumen 958. However, it should be appreciated that if desired
separate lumens can be provided in the flexible elongate member 952
for both of the fittings 961 and 962.
[0221] Self-expanding sealing means 966 is mounted on the distal
extremity 954. This self-expanding sealing means 966 can take any
suitable form. For example, as shown it can consist of a braided
structure 967 formed of a suitable shape memory material such as a
nickel titanium alloy that will attempt to expand to a
predetermined shape memory. Other than shape memory materials,
other materials such as stainless steel, titanium or other
materials can be utilized in the braid 967 as long as they have the
capability of expanding when the self-expanding seal means is
released. Also it should be appreciated that the self-expanding
seal means 966 can be comprised of an absorbent material which when
it absorbs saline or blood expands to form a seal. Such seals can
be readily accomplished because it is only necessary to form a seal
of approximately one atmosphere to prevent small particles from
moving downstream.
[0222] In order to prevent abrasion of a vessel, it is desirable to
cover the braided structure 967 with a covering 968 of a suitable
material such as a polymer which extends over the braided structure
967 and which moves with the braided structure 967 as it expands
and contracts. The polymer can be of a suitable material such as
silicone, C-flex, polyethylene or PET which would form a good
sealing engagement with the wall of the artery.
[0223] Means is provided for compressing the self-expanding sealing
means 966 so that the apparatus can be inserted into the vessel 781
and consists of an elongate sleeve 1071 having proximal and distal
extremities 1072 and 1073 and a bore 1074 extending from the
proximal extremity 1072 to the distal extremity 1073. A collar 1076
is mounted on the proximal extremity 1072 of the sleeve 1071 and is
positioned near the adapter 956. The collar 1076 serves as means
for retracting the sleeve as shown in FIG. 54 to uncover the
self-expanding sealing means 966 after the catheter has been
deployed to permit the self-expanding sealing means 966 to expand
and form a seal with the arterial vessel adjacent the stenosis to
be treated.
[0224] Another embodiment of a catheter apparatus for treating
occluded vessels incorporating the present invention is shown in
FIGS. 55 and 56. As shown therein, the apparatus 1081 consists of a
guiding catheter 1082 having proximal and distal extremities 1083
and 1084. As shown, the distal extremity 1083 is provided with a
pre-formed bend of a conventional type. A conventional attachment
1086 is mounted on the proximal extremity 1083. Self-expanding seal
means 1091 is mounted on the distal extremity 1084 and is of the
type hereinbefore described in connection with the embodiments
shown in FIGS. 53 and 54. A sleeve 1096 similar to the sleeve 1071
of the previous embodiment is provided in the present embodiment
for encasing the self-expanding seal means 1091 and for releasing
the same after it has been disposed in an appropriate position
within a vessel adjacent the occlusion to be treated. Thus a sleeve
1096 is provided having proximal and distal extremities 1097 and
1098 and having a bore 1099 extending from the proximal extremity
to the distal extremity which is sized so that it can receive the
guide catheter 1082. It is provided with a collar 1101 on its
proximal extremity which is adapted to be disposed outside the
patient and which is adapted to be grasped by the physician for
pulling the sleeve 1096 proximally to uncover the self-expanding
seal 1091 after the apparatus has been deployed to permit the
self-expansion of the sealing means 1091 to form a seal with the
vessel wall is shown in FIG. 56.
[0225] In accordance with the hereinbefore described descriptions,
it is apparent that the apparatus can be readily deployed and serve
the same function as the main catheter. To accomplish this, the
assembly 1081 can be introduced into the femoral artery and the
distal extremity advanced into the desired location in the arterial
vessel. After it has been properly positioned, the physician can
retract the sleeve 1096 to permit the self-expanding seal means
1091 to expand and to form a seal with the wall of the arterial
vessel to occlude the arterial vessel and interrupt the flow of
blood in the vessel to provide a working space distal of the
occlusion formed. This prevents small particles which may
thereafter be dislodged from moving downstream. Since a central
lumen is available, the therapeutic procedures hereinbefore
described can be employed with the catheter apparatus shown in
FIGS. 53, 54, 55 and 56.
[0226] Thus it can be seen that it has been possible to
substantially reduce the complexity of the apparatus utilized in
such procedures. This reduces the cost of the apparatus used
therein as well as reducing the time required for performing such
procedures making the procedures less costly.
[0227] It will be appreciated that certain variations of the
present invention may suggest themselves to those skilled in the
art. The foregoing detailed description is to be clearly understood
as given by way of illustration, the spirit and scope of this
invention being limited solely by the appended claims.
* * * * *