U.S. patent application number 10/842848 was filed with the patent office on 2005-02-03 for adjustably stiffenable convertible catheter assembly.
This patent application is currently assigned to Boston Scientific Corporation, a Delaware corporation. Invention is credited to Abele, John E., Andersen, Erik, Reifart, Nikolaus, Tartaglino, Sandra G., Wheeler, Timothy W..
Application Number | 20050027249 10/842848 |
Document ID | / |
Family ID | 32232840 |
Filed Date | 2005-02-03 |
United States Patent
Application |
20050027249 |
Kind Code |
A1 |
Reifart, Nikolaus ; et
al. |
February 3, 2005 |
Adjustably stiffenable convertible catheter assembly
Abstract
A stiffenable balloon catheter assembly capable of being
converted from an "over-the-wire" mode with respect to a guidewire
extending therethrough to a "rapid-exchange" mode with respect to a
guidewire extending therethrough, and vice versa. The catheter has
a plurality of lumens, one lumen however, having a side opening
with an obstructable galp, the orientation of which, determines the
utilization "mode" of the catheter assembly. Stiffening stylets may
be adjustably locked into the lumens, depending upon the "mode", to
control the stiffness of the catheter assembly during its
utilization within a patient.
Inventors: |
Reifart, Nikolaus; (Taunus,
DE) ; Andersen, Erik; (Jvllinge, DK) ; Abele,
John E.; (Concord, MA) ; Tartaglino, Sandra G.;
(Canton, MA) ; Wheeler, Timothy W.; (Upton,
MA) |
Correspondence
Address: |
FISH & RICHARDSON PC
225 FRANKLIN ST
BOSTON
MA
02110
US
|
Assignee: |
Boston Scientific Corporation, a
Delaware corporation
|
Family ID: |
32232840 |
Appl. No.: |
10/842848 |
Filed: |
May 11, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10842848 |
May 11, 2004 |
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08089655 |
Jul 9, 1993 |
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6733473 |
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08089655 |
Jul 9, 1993 |
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08007756 |
Jan 22, 1993 |
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6702781 |
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08007756 |
Jan 22, 1993 |
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07681805 |
Apr 5, 1991 |
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Current U.S.
Class: |
604/103.04 ;
606/194 |
Current CPC
Class: |
A61M 2025/0063 20130101;
A61M 2025/0183 20130101; A61M 25/104 20130101; A61M 2025/1079
20130101 |
Class at
Publication: |
604/103.04 ;
606/194 |
International
Class: |
A61M 029/00 |
Claims
1. A catheter assembly for insertion within a body vessel, said
catheter assembly capable of being converted between an
"over-the-wire" mode and a "rapid-exchange-wire" mode through a
common lumen in said catheter assembly, comprising: an elongated
extruded flexible shaft having a proximal end and a distal end,
said shaft having a balloon arranged about said distal end and a
connector arranged at said proximal end; a first and a second lumen
arranged within said shaft, said second lumen being in fluid
communication with the interior of said balloon for the enablement
of inflation and deflation thereof; and a third lumen extending
between said proximal and distal ends of said shaft, said third
lumen having means therewith to facilitate conversation of said
catheter between an "over-the-wire" mode and a Vapid-exchange-wire"
mode with a guidewire arrangeable through at least a portion of
said third lumen.
2. A catheter assembly for insertion within a vessel as recited in
claim 1, wherein said first lumen has a closed distal end arranged
within said shaft, said first lumen being arranged to receive a
stiffening means therein.
3. A catheter assembly for insertion within a vessel as recited in
claim 1, wherein said means to facilitate conversion of said
catheter form the "over-the-wire" mode to the rapid-exchange-wire)I
mode in said third lumen comprises a side opening disposed through
the wall of said shaft, opening into said lumen to permit a
guidewire to pass therethrough.
4. A catheter assembly for insertion within a vessel as recited in
claim 3, wherein said side opening is disposed in said shaft at a
location proximal to said balloon on said shaft.
5. A catheter assembly for insertion within a vessel as recited in
claim 3, wherein said side opening has a resilient flap extending
thereacross, and within said lumen, to act as a valve to minimize
fluid leakage with respect to said lumen when said catheter is in
said "over-the-wire" mode.
6. A catheter assembly for insertion within a vessel as recited in
claim 2, wherein said stiffening means within said first lumen
comprises a metal stiffening mandrel.
7. A catheter assembly for insertion within a vessel as recited in
claim 6, wherein said stiffening mandrel is made from a metal wire
selected from the group consisting of stainless steel or
Nitinol.
8. A catheter assembly for insertion within a vessel as recited in
claim 6, wherein said stiffening mandrel has a distalmost end which
is emplaced within said catheter shaft, said stiffening mandrel
extending adjacent said side opening distal to the position of said
side opening in said catheter shaft, to minimize kinking within
said shaft.
9. A catheter assembly for insertion within a vessel as recited in
claim 8, wherein said stiffening mandrel is axially displaceable in
said first lumen so as to effect the rigidity of said catheter
shaft therealong.
10. A catheter assembly for insertion within a vessel as recited in
claim 9, wherein said first lumen has a clocking means on its
proximal end, to engage said stiffening mandrel and prevent axial
displacement therewith.
11. A dilatation catheter made from a shaft of extrudable flexible
material having proximal and distal ends, said catheter having an
expandable elongated balloon disposed about its distal end; a first
lumen disposed in said shaft, extending from said proximal end of
said shaft, and having a closed end near the distal end of said
shaft; a third lumen disposed in said shaft comprising a tubular
wall, extending from said proximal end of said shaft, through said
balloon, said lumen having a terminal distal end which is open
distally of said balloon; a stiffening means disposed within said
first lumen; an obstructed opening arranged through said wall of
said third lumen to provide access for a guidewire through the said
lumen distally therepast.
12. A dilatation catheter as recited in claim 11 wherein said
obstructed opening comprises a flexible flap, integral with said
wall, disposed across said opening to permit said lumen to receive
a guidewire through its full length thereof.
13. A dilatation catheter as recited in claim 12, wherein said
opening is disposed through said lumen wall, at an acute angle with
respect to the longitudinal axis of said shaft.
14. A dilatation catheter as recited in claim 11, wherein said
third lumen is adaptable to receive a stiffening stylet and a
guidewire therein, simultaneously.
15. A dilatation catheter as recited in claim 11, wherein said
lumen is adaptable to receive a stiffening stylet and a guidewire
therein, simultaneously.
16. A dilatation catheter as recited in claim 15, wherein said
first lumen has a mandrel locking means at its proximal end
thereof, to permit selective adjustment and engagement of said
stiffening mandrel therein.
17. A dilatation catheter as recited in claim 15, wherein said
closed end of said first lumen is disposed distally on said shaft,
with respect to said obstructed opening, so that when said
stiffening mandrel is fully emplaced therein, said mandrel provides
stiffness and resistance to kinking of said shaft fully across said
obstructed opening.
18. A dilatation catheter from a shaft of extrudable flexible
material having a distal and a proximal end, said having an
elongated expandable balloon disposed about its distal end; a first
lumen disposed in said catheter shaft, open at said proximal end,
sand closed at said distal end, proximal of said balloon, said
first lumen adapted to receive a stiffening mandrel therein; a
second lumen disposed in said catheter shaft, open at said proximal
end, and having its distal end in fluid communication with said
balloon; and a third lumen disposed in said catheter shaft, said
third lumen having a means for converting said dilatation catheter
between an over-the-wire mode an da rapid-exchange-wire mode.
19. A dilatation catheter as recited in claim 18, wherein said
third lumen is adaptable to receive a stiffening stylet and a
separate guidewire therein, simultaneously.
20. A dilatation catheter as recited in claim 19, wherein said
stiffening stylet and said separate guidewire are coaxial while
both are in said third lumen.
21. A dilatation catheter as recited in claim 18, wherein said
means for converting said catheter from an over-thewire mode to a
rapid-exchange mode comprises an acutely disposed opening arranged
through the sidewall of said shaft, and in communication with said
lumen.
22. A dilatation catheter as recited in claim 18, wherein a
plurality of orificci are arranged through the wall of said lumen,
both proximally adjacent and distally adjacent said balloon at the
distal end of said shaft.
23. A dilatation catheter as recited in claim 21, wherein said
acutely disposed opening has a flexible flap arranged thereover and
within said lumen, to provide an obstruction therewithin, said flap
acting as a valve means with respect to said opening.
24. A dilatation catheter as recited in claim 18, wherein said
means for converting said catheter between an "over-the-wire" mode
and a "rapid-exchange" mode comprises an acutely disposed slit
arranged through the sidewall of said catheter shaft, creating a
flexible flap which is bendable to establish an opening in the wall
for passage of a guidewire therethrough.
25. A dilatation catheter as recited in claim 18, wherein said
means for converting said catheter between an "overthe wire" mode
and a Vapid exchange" mode comprises a longitudinal slot disposed
through the sidewall of said catheter shaft, and into said third
lumen, for passage of a guidewire therethrough when said slot is
flexed.
26. A method of performing coronary angioplasty dilatation for
opening a constriction in an artery of a patient, comprising the
steps of: providing an elongated guidewire having distal and
proximal ends and a dilatation catheter comprising a shaft having a
distal and a proximal end, with an elongated expandable balloon
disposed about its distal end, a first lumen with a closed distal
end arranged therein proximal to said balloon, a second lumen in
said shaft open at its proximal end and in fluid communication at
its distal end with said balloon, and a third lumen extending the
length of said shaft and open at each end thereof, said third lumen
having means for converting said catheter between an overthe wire
mode and a rapid-exchange mode, said means for converting said
catheter comprising an obstructed opening through the side wall of
said lumen proximal of said balloon, said first lumen having a
stiffening mandrel therein, the distal end of which extends in said
first lumen distal of said obstructed opening; inserting said
guidewire into the vessel system of a patient; positioning said
catheter over the proximal end of said guidewire so that said guide
wire is in a sliding fit within said third lumen of said shaft;
advancing said guidewire proximally through said third lumen; and
bending said catheter shaft so to as lift said obstruction from
said opening in the side of said third lumen to cause the proximal
end of said guidewire to exit out the side of said third lumen and
extend externally thereof to the proximal end of said catheter,
while positioning said balloon within a vessel obstruction.
27. A method of performing coronary angioplasty dilatation as
recited in claim 26, including the step of: perfusing body fluid
into said third lumen through a plurality of orificii adjacent said
balloon, subsequently perfusing body fluid out of said third lumen
on the other end of said balloon.
28. A method of performing coronary angioplasty dilatation as
recited in claim 27, including the steps of: withdrawing said
catheter shaft from the patient sufficient to bring the proximal
end of said guidewire into juxtaposed correspondence with the side
opening in said third lumen; straightening said catheter shaft at
the location of said opening in said third lumen; and advancing the
proximal end of said guidewire through the proximal balance of said
third lumen while advancing said catheter shaft back into the
vessel system of the patient.
29. A balloon dilatation perfusion catheter, comprising: a balloon
defining a balloon cavity therein; a multi-lumen tubular member
having a proximal end and a distal end extending through the
balloon cavity; a plurality of side openings arranged in the
multi-lumen tubular member located both distal and proximal of the
balloon and in fluid communication with one another via a first
lumen in the multi-lumen tubular member, the first lumen extending
from the proximal end of the multi-lumen tubular member through the
tubular member to an end hole distal of the balloon; a guide wire
outlet opening in the multi-lumen tubular member proximal of the
balloon in communication with the first lumen; and a second lumen
in the multi-lumen tubular member extending from the proximal end
of the multi-lumen tubular member to the balloon and in the fluid
communication with the balloon cavity wherein the first lumen is
provided for receiving a guide wire or a temporary strengthening
wire therein and the second lumen is provided for receiving a
pressure fluid for inflating the balloon.
30. A balloon dilatation perfusion catheter of claim 1 wherein the
guide wire outlet opening has the form of a longitudinal slot.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This is a continuation of application Ser. No. 07/681,805,
filed Apr. 5, 1991.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates to a catheter having a balloon at its
distalmost end, and having means for adjustably controlling the
stiffness of the catheter shaft, and more particularly to a
convertible-type balloon catheter having stiffener means disposed
within the catheter.
[0004] 2. Prior Art
[0005] Balloon catheters are utilized for insert on into the human
body into lumens therewithin. The catheters are of necessity made
of a flexible plastic extrusion such as polyethelene, polester or
polyamide. Advancement and manipulation of a catheter requires a
certain stiffness or pushability of the catheter itself, by the
physician, without injuring the patient in which the catheter is
placed.
[0006] A number of approaches have been made, in attempting to
provide stiffness to catheters. U.S. Pat. No. 4,964,853 to Sugiyama
et al shows a balloon catheter having a braided wire member
disposed within the catheter body itself in a mesh-like manner.
Mesh is imbedded in the wall of the inner tube. U.S. Pat. No.
4,875,841 to Higgins shows a balloon catheter having a coiled wire
arranged within the proximal most hub, which coiled wire extends in
an uncoiled manner within the body of the catheter shaft itself.
The coil and the wire itself being co-rotatable so as to provide
rotational stiffness to the catheter.
[0007] U.S. Pat. No. 4,822,345 to Danforth shows a variable
stiffener balloon catheter, for percutaneous transluminal coronary
angioplasty procedures. This patent to Danforth shows a method of
providing for variable flexibility, by the use of a longitudinally
extended balloon arranged along the exterior of the catheter shaft.
Pressurization or depressurization of this balloon is effectuated
by a syringe, which pressurizably controls the rigidity of the
balloon itself. A further embodiment of this concept of Danforth
utilizes relatively stiff wires running through channels in the
periphery of the catheter, the wires adding the stiffness to the
catheter.
[0008] The preformed catheter assembly shown in U.S. Pat. No.
4,738,667 to Galloway discloses a sheath which is slideably mounted
over the catheter so as to be moved from the proximal to the distal
end, to straighten out the distal end during insertion and removal
of the catheter from a body. The catheter assembly shown in U.S.
Pat. No. 4,737,152 to Alchas shows a stylet or stiffening wire
arranged within a lumen connected to the closed distal end of the
catheter and also there is a loop on its proximalmost end. The loop
is arranged in a rotatable knob to facilitate rotation of the
distal end of the catheter while providing stiffness, while the
proximal end is turned.
[0009] U.S. Pat. No. 4,586,923 issued to Gould et al shows a
curving tip catheter having a catheter body which includes a sheath
of braided wire having a meshlike configuration positioned around
the wall of the tubular body to provide tortional stiffness to the
body relative to the flexible tip. In an alternative embodiment, a
relatively stiff but bendable inner plastic tubing can be inserted
within the tubular body to provide tortional stiffness to that
body. In a somewhat similar vein, U.S. Pat. No. 4,516,972 to
Sampson shows a guiding catheter having a helically wound ribbon of
flexible material embedded within the wall of the catheter, so as
to provide tortional rigidity and stiffness.
[0010] In yet a further embellishment on the idea of stiffening a
balloon catheter, U.S. Pat. No. 4,448,195 to LeVeen et al shows a
reinforced balloon catheter which has a guidewire adapted to be
inserted for stretching the catheter when it is inserted into a
blood vessel to stiffen the catheter and position it. In an
alternative arrangement, a braided shell wire reinforcement is used
within the braids, which are placed at the beginning and endings of
the thinned portion of the catheter. U.S. Pat. No. 4,033,331 to
Guss et al, discloses a contour or stiffening wire slideably
disposed within a lumen extending substantially the full length of
the catheter. Slight retraction of the stiffening wire from the
distal end of the lumen permits catheter to assume a predetermined
curvature thereat.
[0011] It is thus an object of the present invention to provide a
catheter having variable stiffness capabilities therewithin. The
catheter of the present invention should overcome the problems of
the prior art by getting the physician to properly adjust the
rigidity or stiffness of the catheter shaft according to the
particular situation that warrants it in conjunction with the
capability of utilizing the catheter shaft in a convertible manner
between a "rapid-exchange" mode and an "over-the-wire" mode.
BRIEF SUMMARY OF THE INVENTION
[0012] The present invention comprises a balloon catheter having a
catheter shaft with at least three lumens extending from the
proximal to the distal ends thereof. The first and second lumens
may preferably but not necessarily be of cresent shape in
cross-section, and the third lumen is of circular cross-section. At
least one of the cresent shaped lumens has a stiffening mandrel
extending therethrough. In a preferred embodiment, the third lumen
has a side opening arranged relatively close yet proximal to the
balloon at the distal end of the catheter assembly.
[0013] The balloon on the distal end of the catheter shaft is in
fluid communication with one of the cresent shaped lumens. The
first shaped lumen has a closed distalmost end, at the proximal end
of the balloon.
[0014] The third lumen, preferably of circular cross-section,
extends from the proximal end of the catheter shaft, and through
the balloon, open at its distalmost end at the distal end of the
balloon. The third lumen is adapted to receive a guidewire, either
through the entire length thereof, or from an opening proximal of
the balloon and through to its distalmost end.
[0015] In a preferred embodiment, a guidewire is adaptable to enter
the third "distal" lumen at its opening at the distalmost end of
the catheter and extend through that lumen, through the balloon,
and exit out the side opening through the sidewall of the catheter,
proximal of the balloon. The side "guidewire" opening of the third
lumen being disposed through the wall of the catheter shaft at a
location which is also proximal to the distal end of the stiffening
mandrel in the first cresent shaped lumen. This rapid exchange mode
with a guidewire extending partway through may occur with a
stiffening stylet disposed within the third lumen, the stylet
extending up to a location adjacent the side opening, from the
proximal end of the catheter. This same lumen, a portion of which
is utilized for the "rapid-exchange" mode, is utilized in its
entire length, for the catheter in its "over-the`wire" mode, where
a guidewire enters the distal opening of the third "distal" lumen,
and exits at the proximal end of the catheter at the proximal end
of that third lumen, through a connector or adaptor.
[0016] The present invention thus comprises a multiple lumen
catheter (at least three lumens) having proximal and distal 15
ends, the proximal end having a Y-connector thereat for adaptation
of inflation devices or control functions, the distal end
comprising an inflatable elongated balloon.
[0017] A first of the lumens has an elongated stiffening mandrel
disposed therein, the lumen being closed at its distalmost end. The
stiffening mandrel being preferably made of Nitinol. A second of
the lumens extending from the connector, and into the balloon,
providing fluid communication therewith. The third of the lumens
being preferably circular in cross-section, extending from the
connector and through the balloon, and open through the distal tip
of the catheter shaft. A "side" orifice being disposed through the
wall of the catheter and into the third lumen, just proximal (about
15 to 35 cm) of the balloon. The stiffening mandrel in the first
lumen extending distally of the side orifice in the third lumen to
the proximal end of the catheter, so as to allow a smoother
transition of catheter stiffness when the assembly is utilized in a
rapid exchange mode--that is, when a guidewire extends only part
way through the third lumen, out through the "side" orifice after
entering that lumen distally and to help transmit "push" on the
catheter shaft from its proximal end. The same lumen therefore, in
the same catheter, functioning as a lumen for an "over-the-wire"
mode, as well as a "rapid-exchange-wire" mode, using part of the
lumen for a guidewire and part of that lumen for catheter
stiffening assistance.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The objects and advantages of the present invention will
become more apparent when viewed in conjunction with the following
drawings, in which:
[0019] FIG. 1 is a sectional side-elevational view of the distal
portion of a catheter assembly constructed according to the
principles of the present invention;
[0020] FIG. 1a is an enlarged view of the "side opening" shown in
cross-section in FIG. 1;
[0021] FIG. 2 is a cross-sectional view taken along the lines.
II-II of FIG. 1;
[0022] FIGS. 3a, 3b, and 3c are side-elevational views of
stiffening mandrels contemplated with this catheter assembly;
[0023] FIG. 4 is a side-elevational view of a catheter assembly
showing a bifucated connector therewith;
[0024] FIG. 5 is a side-elevational view of the proximal end of the
catheter assembly showing a trifurcated connector therewith;
[0025] FIG. 6 is a side-elevational view of the catheter assembly
in an "over-the-wire" mode;
[0026] FIG. 7 is a side-elevational view of the catheter assembly
in a "rapid exchange mode" configuration; and
[0027] FIG. 8 is a side-elevational view of the catheter assembly
in a further embodiment thereof.
[0028] FIG. 9 is a side view of a part of a catheter shaft, in a
further-embodiment of the side opening;
[0029] FIG. 10 is a plan view of the opening-shown in FIG. 9;
[0030] FIG. 11 is a side view of part of a catheter shaft in yet a
further embodiment or the side opening, and;
[0031] FIG. 12 is a plan view of the opening shown in FIG. 11.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0032] Referring to the drawings now in detail, and particularly to
FIG. 1, there is shown the distal portion of a catheter assembly
10, also shown in its extendedmost form in FIG. 4. The catheter
assembly 10 comprises an extruded catheter shaft 12 having a
plurality of lumens disposed axially therethrough. The catheter
shaft 12 has a first lumen 14, and a second lumen 16, both of which
are preferably, but not necessarily of cresent shape, as shown in
the cross-sectional view of FIG. 2. The catheter shaft 12 also
includes a third lumen 18, which is preferably of circular
cross-section.
[0033] The catheter shaft 12 has an elongated balloon 20 disposed
about its distalmost end, in a known manner. The first lumen 14
extends from an opening, not shown, in a connector 22, shown in
FIG. 4, distally towards a closed end 24, at the proximal end of
the balloon 20. A stiffening mandrel 26, as shown in FIG. 1, is
disposed within the length of the first lumen 14. The stiffening
mandrel 26 may have a ball welded tip 28 or be otherwise tapered
and flexible on its distalmost end, to prevent puncture of the
lumen 14 by the mandrel 26.
[0034] The second lumen 16 extends from the connector 22, through
the shaft 12, parallel to the first lumen 14, except that the
second lumen 16 is in fluid communication with the balloon 20, as
shown in phantom lines 17, in FIG. 1. The second lumen 16 provides
a conduit for pressurized fluid for inflating and deflating the
balloon 20 from an inflation/deflation device, not shown, which
would be adaptable to the connector 22. It is to be noted that the
view of FIG. 1 is sectioned to show the first lumen 14 and the
third lumen 18, and not longitudinally bisect the web of material
19 separating the first and second lumens 14 and 16.
[0035] The third lumen 18, of generally circular cross-section,
extends from the connector 22, through the shaft 12, and through
the balloon 20, opening distally of the balloon.20, as shown in
FIGS. 1 and 1A. The third lumen 18 is not in fluid communication
with the balloon 20.
[0036] An opening or side orifice 30 is disposed through the wall
of the catheter shaft 12, and into the third lumen 18, as shown in
FIG. 1. The side opening 30 in this preferred embodiment is
preferably a slightly oval opening of about 3 mm long and 0.5 mm
wide, arranged at a sharp angle. "A" of about 20 to about 60
degrees with respect to the longitudinal axis of the shaft. The
side opening 30 includes a valve-like cover flap 32, integral with
the shaft 12 with a distally tapering edge 33, the flap 32 being
about the size to cover the opening 30, and is resilient so as to
allow it flex over the opening 30, and within the third lumen 18,
obstructing it somewhat, depending upon how the flap 32 is being
biased. The side opening 30 is disposed a distance "x" of about 15
to about 35 cm. from the proximal end of the inflated balloon 20,
as shown in FIGS. 1 and 4. The third or "distal" lumen 18 may thus
be utilized in its entire length, from the proximal connector 22 to
its distalmost orifice, for receiving a guidewire in an
"over-the-wire" mode, the flap 32 roughly covering the inside of
the opening 30. The lumen 18 may also be utilized, from the opening
30 to its distal end, in a "rapid-exchange-wire" mode with a
guidewire extending through the distal end of the third lumen 18
and out the opening 39 once the flap 32 is flexed out of the
way.
[0037] An RO (radio opaque) marker band 34 is disposed about the
catheter shaft 12, (essentially the structure comprising the third
lumen 18), at the mid-point of the balloon 20 in either the
"over-the-wire" mode or the "rapid-exchange" mode.
[0038] In one embodiment of the present invention, where the
catheter assembly 10 is utilized as aforementioned in the
traditional "over-the-wire" catheter, a guidewire 50, normally
initially having been inserted into a patient's vessel, and having
its proximal end outside of the patient, has that proximal end
inserted through the distal end of the catheter assembly 10,
through the "distal" or third lumen 18, and it extends proximally,
out of the proximal guidewire connector 42, as shown in FIG. 6. The
flap 32 performs basically like a valve, by shutting itself against
the opening 30, thus permitting an unobstructed lumen for passage
of the guidewire 40, or for passage of pressurized fluid injected
proximally in the lumen 18 to pass through the lumen 18, to escape
primarily out of the distal end of the catheter shaft 12 through
the lumen 18.
[0039] In a further embodiment of the present invention, where the
catheter assembly 10 may be utililized in the aforementioned
"rapid-exchange" mode, the guidewire 50, normally initially
inserted into a patient's vessel, and having its proximal end
outside of the patient, has that a proximal end inserted through
the distal end of the catheter assembly 10, through the "distal"
lumen 18, and extending outwardly proximally, through the side
opening 30 as shown in FIGS. 1 and 7. The guidewire 50 in this
mode, extends parallel to and external of the shaft 12, proximal of
the side opening 30. The enlarged view in FIG. 1A depicts the
guidewire 50 shown in phantom lines, and the flap 32 in close
fitting overlapping relationship to the guidewire 50. During the
threading of the guidewire through the distal lumen 18, it is
anticipated that the shaft 12 would be bent into a "U" shape at the
opening 30, with the opening 30 in the trough of the "U", so as to
cause the flap 32 to bend "away" from the opening 30, obstructing
the lumen 18 proximally therepast to permit the guidewire 50 to be
threaded through the lumen 18 and out the opening 30.
[0040] Additionally, when the catheter assembly 10 is utilized in
this "rapid-exchange" mode, a stiffening stylet 52 may be inserted
within the "distal" or third lumen 18 through the connector 22, as
shown in FIGS. 1, 1A and 2. The stiffening stylet 52 has a distal
end 54 which would extend only up to the side opening 30, and no
further. The stiffening stylet 52 may have several different
configurations, such as shown in FIG. 3A, 3B or 3C. The stylet 52
shown in FIG. 3A, is a straight mandrel 54, having uniform diameter
along its entire length. The stylet 52 shown in FIG. 3B, is a
tapered mandrel 56, having an initial diameter (its non-tapered
end) of about 0.20 inches, and tapering about 5 cm. or more along
its distal length 57 to a diameter of about 0.008 inches. The
stylet 52 shown in FIG. 3C is a tapered mandrel 58, similar to the
mandrel 56 shown in FIG. 3B, but having a ball weld 60 therein, of
a diameter of about 0.020 inches. Each stylet 52 may be made from a
stainless steel or Nitinol material, in a known manner.
[0041] It is critical to the present invention that the location of
the distalmost end of the stiffening mandrel 26 emplaced within the
first lumen 14, as shown in FIG. 1 be juxtaposed distal to the
location of the side hole 30 in the distal lumen 18 of the shaft
12. FIG. 5 shows a trifurcated connector 59 mounted on the proximal
end of a catheter shaft 12 having a locking hub 61 which would be
arranged to adjustably lock at stiffening stylet 26 within the
first lumen 14 if desired. A further locking hub 63 may be arranged
off of the connector 59 to adjustably seize a stiffening mandrel 52
in the third lumen 18 for longitudinal adjustment thereof, at the
physicians option, while the catheter is being utilized in the
"rapid-exchange" mode.
[0042] FIG. 8 shows a further adaptation of the catheter assembly
10, wherein a plurality of orificii 664is disposed through the wall
of the catheter sheath 12 to provide fluid communication with the
distal lumen 18 from the outside of the catheter shaft 12 at a
location proximal of the balloon 20, and distal of the side hole
30. The orificii 66 are about 0.025 inches in diameter, and
function as openings for 20 passive perfusion. A further similar
plurality of orificii 68 is disposed through the wall of the sheath
12 and distal of the balloon 20, to provide fluid communication
with the distal lumen 18, to function as openings for passive
perfusion with respect to that lumen 18.
[0043] A further embodiment of the side hole 30 is shown in FIG. 9,
wherein a portion of a catheter shaft 74 has a "distal" lumen 76
extending therethrough, in a manner similar to the aforementioned
catheter shaft 12. A slit 78 is cut diagonally through the outer
wall of the catheter shaft 74, making a flap 80, which when
flexibly lifted away from the lumen 76 provides a "D" shaped
opening, through which a guidewire 82 may be passed. FIG. 10 shows
the flap 80 in its "at rest" configuration, with the "D" shaped
opening closed, to provide a full passage lumen 76
thereadjacent.
[0044] A yet another embodiment of the side hole 30 is shown in
FIG. 11, wherein a portion of a catheter shaft 84 has a "distal"
lumen 86 extending therethrough. A slot 88 about 2 cm. long and
0.05 cm wide is diposed longitudinally through the outer wall of
the catheter shaft 84, to make a flexibly openable orifice which a
guidewire 90 may be passed. FIG. 12 shows the slot 38 in a plan
view, in its "at rest" configuration.
[0045] Thus what has been shown is a novel stiffened catheter
assembly 10 capable of being utilized by a physician as an
"over-the-wire" catheter with adjustable stiffness means therewith,
or optionally as a "rapid-exchange-wire" catheter apparatus, also
including the capability of being able to control or vary the
stiffness of the catheter shaft by selective insertion and/or
controlled withdrawal of a stiffening stylet adaptably arranged
within the guidewire lumen, the "rapid-exchange-wire" mode being
facilitated by a side opening having valve-like obstructable flap
across its inner side to minimize fluid exchange when that lumen
accepts the catheter to be utilized in its full length
"over-the-wire" mode. In its use as either a "rapid-exchange-wire"
or an "over-the-wire" mode, the portion of the "distal" lumen
enclosing the guidewire may have a plurality of orificii through
the wall of the catheter shaft just proximal and just distal of the
elongated inflated balloon, to permit perfusion of body fluid
across the then expanded balloon in the body vessel.
* * * * *