U.S. patent application number 11/111394 was filed with the patent office on 2006-11-09 for guiding catheter with resiliently compressible occluder.
This patent application is currently assigned to Medtronic Vascular, Inc.. Invention is credited to Michael S. Noone.
Application Number | 20060253099 11/111394 |
Document ID | / |
Family ID | 37394982 |
Filed Date | 2006-11-09 |
United States Patent
Application |
20060253099 |
Kind Code |
A1 |
Noone; Michael S. |
November 9, 2006 |
Guiding catheter with resiliently compressible occluder
Abstract
A guiding catheter for providing proximal occlusion while
intubating a branch vessel lumen in a patient. The catheter
comprises an elongate hollow shaft having open proximal and distal
ends and a resiliently compressible occluder fixed about the shaft
adjacent the distal end, the occluder having a relaxed shape that
tapers distally from a major diameter greater than a diameter of
the vessel lumen. The occluder may comprise elastic foam material
or an impermeable flexible cover clingingly enclosing a resilient
support member.
Inventors: |
Noone; Michael S.;
(Londonderry, NH) |
Correspondence
Address: |
MEDTRONIC VASCULAR, INC.;IP LEGAL DEPARTMENT
3576 UNOCAL PLACE
SANTA ROSA
CA
95403
US
|
Assignee: |
Medtronic Vascular, Inc.
Santa Rosa
CA
|
Family ID: |
37394982 |
Appl. No.: |
11/111394 |
Filed: |
April 21, 2005 |
Current U.S.
Class: |
604/509 ;
604/104; 604/96.01 |
Current CPC
Class: |
A61M 25/10 20130101;
A61M 2025/1052 20130101; A61M 2025/0681 20130101 |
Class at
Publication: |
604/509 ;
604/104; 604/096.01 |
International
Class: |
A61M 31/00 20060101
A61M031/00 |
Claims
1. A guiding catheter for intubating a branch vessel in a patient,
the vessel having an ostium, a lumen and a lumen wall, the catheter
comprising: an elongate hollow shaft having open proximal and
distal ends; and a resiliently compressible occluder sealingly
fixed about the shaft adjacent the distal end and having a relaxed
size and shape including a major diameter adapted to be wedged past
the vessel ostium into the lumen to provide sealing engagement with
the lumen wall, the occluder lacking fluid or mechanical actuation
from the shaft proximal end.
2. The guiding catheter of claim 1, wherein the relaxed shape of
the occluder tapers distally from the major diameter and is
asymmetrically biconical, conical, ellipsoidal, symmetrically
biconical, or ovoidal.
3. The guiding catheter of claim 1, wherein the occluder comprises
an elastic foam material.
4. The guiding catheter of claim 3, wherein the elastic foam
material is latex, silicone elastomer, butadiene/acrylonitride
copolymers, copolyesters, ethylene vinylacetate (EVA) polymers,
ethylene/acrylic copolymers, ethylene/propylene copolymers,
polyalkylacrylate polymers, polybutadiene, polybutylene,
polyethylene, polyisobutylene, polyisoprene, polyurethane,
styrenebutadiene copolymers, or
styrene-ethylene/butylene-styrene.
5. The guiding catheter of claim 1, wherein the occluder comprises
a resilient support member clingingly enclosed by an impermeable
flexible cover.
6. The guiding catheter of claim 5, wherein the flexible cover
comprises a biocompatible material selected from the group
consisting of latex, silicone elastomer, natural rubber, synthetic
rubber, butadiene/acrylonitride copolymers, copolyesters, ethylene
vinylacetate (EVA) polymers, ethylene/acrylic copolymers,
ethylene/propylene copolymers, polyalkylacrylate polymers,
polyamide, polybutadiene, polybutylene, polyethylene, polyethylene
terephthalate, polyisobutylene, polyisoprene, polyolefin,
polypropylene, polyurethane, polyvinyl chloride, styrenebutadiene
copolymers, or styrene-ethylene/butylene-styrene.
7. The guiding catheter of claim 5, wherein the flexible cover has
proximal and distal ends, the cover proximal end being sealingly
attached to the catheter shaft.
8. The guiding catheter of claim 5, wherein the resilient support
member comprises a tubular body having a plurality of struts
generated by a plurality of longitudinal slits, the plurality of
struts being pre-formed in the relaxed size and shape of the
occluder.
9. The guiding catheter of claim 8, wherein the tubular body is a
high-modulus thermoplastic or thermo-set plastic, nitinol (TiNi),
stainless steel or a work-hardenable super alloy comprising nickel,
cobalt, chromium and molybdenum.
10. The guiding catheter of claim 8, wherein the plurality of
struts extends between proximal and distal ends of the tubular
body.
11. The guiding catheter of claim 10, wherein at least one of the
proximal and distal ends of the tubular body is intact and slidably
mounted on the catheter shaft.
12. The guiding catheter of claim 10, wherein the cover proximal
end is sealingly attached to the tubular body proximal end.
13. The guiding catheter of claim 1, wherein the shaft comprises a
biocompatible material selected from the group consisting of
polyamide, polyester, polyethylene, polyethylene block amide
copolymer, polyolefin, polypropylene and polyurethane.
14. The guiding catheter of claim 1, wherein a distal region of the
shaft is pre-formed into a curvilinear shape.
15. The guiding catheter of claim 1 further comprising a connector
fitting coupled to the shaft proximal end.
16. A method of using a guiding catheter comprising: providing a
guiding catheter in accordance with claim 1; inserting the catheter
shaft distal end into a vascular system of the patient; advancing
the catheter shaft distal end to the branch vessel in the patient;
intubating the vessel with the catheter shaft distal end; wedging
the compressible occluder into the vessel lumen; and passing the
major diameter of the occluder beyond the vessel ostium and into
sealing engagement with the wall of the vessel lumen to provide
occlusion of blood flowing there through.
17. The method of claim 16 further comprising: inserting an
introducer sheath into the vascular system of the patient, and
wherein inserting the catheter shaft distal end further comprises
wedging the compressible occluder through the introducer
sheath.
18. The method of claim 17, wherein advancing the catheter shaft
distal end to a branch vessel in the patient further comprises:
allowing the resilient support member to resume the relaxed shape
thereof.
19. The method of claim 16 further comprising: inserting a
therapeutic device through the guiding catheter; and operating the
therapeutic device to treat the patient from within the branch
vessel.
20. The method if claim 19, wherein the therapeutic device is an
angioplasty catheter and operating the therapeutic device comprises
inflating a balloon to dilate a stenosis in the vessel.
Description
FIELD OF THE INVENTION
[0001] The present invention relates generally to an intraluminal
guiding catheter used for intubation of a branch vessel, and more
particularly, to a guiding catheter with a resiliently compressible
occluder disposed adjacent the distal end of the catheter.
BACKGROUND OF THE INVENTION
[0002] Stenotic lesions form on the lumen walls of blood vessels to
create narrowings that restrict blood flow through the vessel, and
may comprise a hard, calcified substance and/or a softer thrombus
material. Interventional catheterization procedures such as balloon
angioplasty, stent deployment, atherectomy, and thrombectomy are
well known and have proven effective in the treatment of such
stenotic lesions. Such modalities require the passage of a therapy
catheter through a patient's vasculature and into a targeted branch
vessel.
[0003] Recently, a variety of devices have been developed to
address atheroembolization, which is the obstruction of blood
vessels by stenotic debris released during interventional
catheterization therapies such as those mentioned above. Distal
protection devices (DPDs) such as filters and occluders represent
one class of intravascular devices that can be used to prevent
atheroembolization. A filter mounted on a guidewire or a catheter
may be positioned distally of a stenosis to capture and remove
potentially embolic debris without causing hemostasis during use of
the filter. Alternatively, an occluder device may be positioned
distally of a stenosis to temporarily stop the flow of blood,
including any stenotic debris that may have become entrained in the
blood. The contaminated blood is aspirated from the treated area
before the distal occluder device is collapsed to permit resumption
of blood flow.
[0004] Occlusion devices may also be placed proximally of a
stenosis to provide so-called proximal protection. Proximal
occlusion devices may be used alone to prevent atheroembolization,
or they may be used in conjunction with a distal occluder to form
an isolated treatment chamber about the stenosis to be treated.
Preliminary deployment of a proximal occlusion device may be
advantageous in preventing atheroembolization because advancing a
treatment catheter, a guidewire or a DPD into a stenosis can
dislodge particulate debris, even before the stenosis is being
opened. Proximal occlusion can create temporary hemostasis in the
vessel to prevent distal embolization by debris created during
crossing and/or treatment of the lesion. As is done with distal
occlusion, contaminated blood is aspirated from the treated area
before the proximal occluder device is collapsed to permit
resumption of blood flow.
[0005] Known occluder devices typically employ an inflatable
occlusion balloon or a mechanically expandable occluder element
with their attendant expansion apparatuses. For a proximal
occlusion device such as a guiding catheter, an occlusion balloon
requires an inflation lumen extending around or alongside a main
lumen to provide fluid actuation of the balloon from the proximal
end of the catheter. A guiding catheter having a mechanically
expandable occluder typically requires a slidable sleeve or
push/pull wire for mechanical actuation of the occluder from the
proximal end of the catheter. Adding an extra lumen or additional
actuator features to a guiding catheter disadvantageously require
the outside diameter to be larger, and/or the inside diameter of
the main lumen to be smaller. Thus, a need exists for a guiding
catheter having an atheroembolization prevention system that does
not require increasing the wall thickness of the guiding catheter.
Such a guiding catheter should be operable simply and quickly
during interventional catheterization procedures. Other desirable
features and characteristics of the present invention will become
apparent from the subsequent detailed description and the appended
claims taken in conjunction with the accompanying drawings.
BRIEF SUMMARY OF THE INVENTION
[0006] The present invention pertains to a guiding catheter for
providing proximal occlusion while intubating a branch vessel lumen
in a patient. The catheter comprises an elongate hollow shaft
having open proximal and distal ends and a resiliently compressible
occluder fixed about the shaft adjacent the distal end, the
occluder having a relaxed size and shape that tapers distally from
a major diameter greater than a diameter of the vessel lumen. The
occluder does not require any type of actuation from the proximal
end of the catheter. The occluder may comprise elastic foam
material or a resilient support member clingingly enclosed by an
impermeable flexible cover.
[0007] A method is also disclosed for using the inventive guiding
catheter. The method includes providing a guiding catheter having
one of the embodiments described above, compressing the resilient
occluder while inserting the guiding catheter into the vascular
system of the patient, advancing the catheter shaft distal end to a
branch vessel in the patient, and intubating the vessel with the
catheter shaft distal end such that the occluder is wedged into the
vessel lumen until the major diameter of the occluder passes beyond
a vessel origin and into sealing engagement with a wall of the
vessel lumen to provide occlusion of blood flowing there
through
[0008] In other embodiments of the invention, the method may also
include inserting a therapeutic device through the guiding
catheter, and operating the therapeutic device to treat the patient
from within the targeted branch vessel.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The following drawings are illustrative of particular
embodiments of the invention and therefore do not limit its scope.
They are presented to assist in providing a proper understanding of
the invention. The drawings are not to scale and are intended for
use in conjunction with the explanations in the following detailed
descriptions. Like reference numerals denote like elements in the
drawings, wherein;
[0010] FIG. 1 is a side view of one embodiment of a guiding
catheter in accordance with the invention, wherein an occluder is
shown in a relaxed configuration;
[0011] FIG. 2 is a side view of another embodiment of a guiding
catheter in accordance with the invention, wherein an alternative
occluder is shown in a relaxed configuration;
[0012] FIG. 3 is a perspective view of a distal portion of the
embodiment shown in FIG. 2, wherein the occluder is shown in a
compressed configuration;
[0013] FIG. 4 illustrates one embodiment of a guiding catheter in
accordance with the invention, shown deployed in the cardiovascular
system of a patient; and
[0014] FIGS. 5-8 are longitudinal cross-sectional views that
illustrate the use of the inventive guiding catheter in a diseased
vessel during an angioplasty procedure.
DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION
[0015] The following detailed description is merely exemplary in
nature and is not intended to limit the invention or the
application and uses of the invention. Although the description of
the invention is in the context of protection against
atheroembolization during treatment of blood vessels such as the
coronary, carotid and renal arteries, the invention may also be
used in any other passageways where it is deemed useful to provide
temporary occlusion to block fluid flow. Furthermore, there is no
intention to be bound by any expressed or implied theory presented
in the preceding technical field, background, brief summary or the
following detailed description.
[0016] FIG. 1 illustrates one embodiment of guiding catheter 100,
including catheter shaft 105, optional soft tip 110, connector
fitting 115 and resiliently compressible occluder 117 shown in a
normal, or relaxed, expanded configuration. Lumen 120 extends
through shaft 105 between open proximal and distal ends, and is
sized and shaped to receive and direct there through a variety of
treatment devices such as guidewires and/or therapeutic devices
including, but not limited to balloon catheters or stent delivery
systems.
[0017] Occluder 117 is mounted around catheter shaft 105 adjacent
to the distal end thereof, and is made from a resilient, or
elastic, biocompatible foam material that is soft enough to be
compressed when occluder 117 is wedged into a vessel lumen during
intubation by the guiding catheter distal end. Occluder 117 is also
soft enough to be compressed as it is wedged into an introducer
sheath (see element 460 in FIG. 4) during insertion of catheter 100
into the patient. The elastic foam material comprising occluder 117
may be latex, silicone elastomer, or other viscous forms of natural
and synthetic rubbers such as butadiene/acrylonitride copolymers,
copolyesters, ethylene vinylacetate (EVA) polymers,
ethylene/acrylic copolymers, ethylene/propylene copolymers,
polyalkylacrylate polymers, polybutadiene, polybutylene,
polyethylene, polyisobutylene, polyisoprene, polyurethane,
styrenebutadiene copolymers, or styrene-ethylene/butylene-styrene.
The elastic foam material may be closed-cell or open-cell, although
if it is open cell, then means must be provided to seal the
porosity of the material so that it can function as an occluder.
Flexible cover 235, as will be described further below, may be used
to seal an open cell foam occluder.
[0018] Occluder 117 has a normal, or relaxed size and shape that,
when wedged past an ostium or origin of a branch vessel, will
compress to effect sealing engagement with the wall of the vessel
lumen. To achieve such a sealing engagement, the relaxed shape of
occluder 117 has a diameter at its broadest transverse section, or
major diameter 125 that is greater than the diameter of the vessel
lumen. To help to prevent injury to the ostium or the wall of the
vessel lumen as occluder 117 is wedged into sealing engagement, the
relaxed shape of occluder 117 includes taper 130 extending distally
from major diameter 125. Taper 130 may be a distal portion of a
relaxed shape selected from a variety of possible shapes of
occluder 117. Similarly, to help to prevent injury to the ostium or
the wall of the vessel lumen as occluder 117 is withdrawn with
guiding catheter 100, the relaxed shape of occluder 117 may also
include a taper extending proximally from major diameter 125. The
distal and proximal tapers may be similar or different, and they
may be curved rather than purely conical. For example, the relaxed
shape of occluder 117 may be asymmetrically biconical, conical,
ellipsoidal, symmetrically biconical, or ovoidal. Occluder 117 may
be attached to shaft 105 by any suitable manner known in the art,
for example, a biocompatible adhesive such as a cyanoacrylate.
[0019] Catheter shaft 105 is a flexible shaft that is designed to
be advanced through a patient's vasculature to remote arterial
locations without buckling or undesirable bending. As shown in FIG.
4, and as is well known to those of skill in the art, catheter
shaft 105 may include a pre-formed distal curve 101 that can aid in
traversing a patient's vasculature, or can provide enhanced "backup
support" as therapeutic catheters are advanced through lumen 120 of
guiding catheter 100 and across a stenosis. Any one of a number of
pre-formed curvilinear shapes may be incorporated into guiding
catheter 100, such as Judkins-type or Amplatz-type curves, as
non-limiting examples. Catheter shaft 105 may be constructed of one
or more flexible biocompatible materials, including, but not
limited to, polyamide, polyester, polyethylene, polyethylene block
amide copolymer, polyolefin, polypropylene and polyurethane.
Catheter shaft 105 may also include a layer of braided filaments
that resists kinking and enhances longitudinal transmission of
rotation. To further aid in advancing guiding catheter 100 through
the patient's vasculature, it may be desirable to vary the
stiffness of catheter shaft 105 by varying the braid pitch, by
varying the properties of the materials used in constructing the
catheter, or by combining both techniques. The distal end of
catheter shaft 105 may include soft tip 110 formed thereon via any
of numerous methods known to those skilled in the art.
[0020] Connector fitting 115 is coupled to, and provides a
functional access port at the proximal end of guiding catheter 100.
Connector fitting 115 may be made of metal or of a hard polymer
(e.g. medical grade polycarbonate, polyvinyl chloride, acrylic,
acrylonitrile butadiene styrene (ABS), or polyamide) that possesses
the requisite structural integrity, as is well known to those of
skill in the art.
[0021] Lumen 120 of guiding catheter 100 may include a slippery
interior surface for reducing frictional forces between the
interior surface and devices that may be moved through lumen 120.
In one exemplary embodiment, the interior surface is provided with
a slippery coating, such as a silicone compound or a hydrophilic
polymer. In another exemplary embodiment, the interior surface
includes a liner formed from a slippery material. Those with skill
in the art may appreciate that any one of numerous low-friction,
biocompatible materials such as, for example, fluoropolymers (e.g.
PTFE, FEP), polyolefins (e.g. polypropylene, high-density
polyethylene), or polyamides, may be used for the liner.
[0022] FIG. 2 illustrates another embodiment of the invention
wherein guiding catheter 200 includes catheter shaft 205 (similar
to catheter shaft 105), optional soft tip 210 (similar to soft tip
110), connector fitting 215 (similar to connector fitting 115) and
resiliently compressible occluder 217 shown in a normal, or
relaxed, expanded configuration. Lumen 220 (similar to lumen 120)
extends through shaft 205 between open proximal and distal ends,
and is sized and shaped to receive and direct there through a
variety of treatment devices such as guidewires and/or therapeutic
devices including, but not limited to balloon catheters or stent
delivery systems.
[0023] Occluder 217 is mounted around catheter shaft 205 adjacent
the distal end thereof and includes tubular, resilient, support
member 230 clingingly encased by impermeable flexible cover 235.
FIG. 3 shows resilient occluder 217 in a compressed configuration,
as it might appear when wedged into an introducer sheath or into a
vessel lumen beyond the ostium thereof. Support member 230 includes
proximal and distal ends 250, 255, respectively. A plurality of
longitudinal slits 240 extends between proximal and distal ends
250, 255 to generate a plurality of longitudinal struts 245. At
least one of support member ends 250, 255 is intact, in that slits
240 do not extend all the way to the end of support member 230.
Flexible cover 235 clings to struts 245, spanning the open slits
there between to make occluder 217 impermeable to fluid in a
patient's vessel. Flexible cover 235 may be formed from an elastic
material such as latex, silicone elastomer, or other viscous forms
of natural and synthetic rubbers such as butadiene/acrylonitride
copolymers, copolyesters, ethylene vinylacetate (EVA) polymers,
ethylene/acrylic copolymers, ethylene/propylene copolymers,
polyalkylacrylate polymers, polybutadiene, polybutylene,
polyethylene, polyisobutylene, polyisoprene, polyurethane,
styrenebutadiene copolymers, and styrene-ethylene/butylene-styrene.
Alternatively, flexible cover 235 may be formed from an inelastic
material that is thin, flexible and foldable, such as polyamide,
polyethylene, polyethylene terephthalate, polyolefin,
polypropylene,. or polyvinyl chloride.
[0024] One of support member ends 250, 255 may be slidably mounted
along catheter shaft 205, with the other end being fixed to
catheter shaft 205 by any suitable manner known in the art, such as
epoxy adhesive or cyanoacrylate. For example, proximal end 250 may
be sealingly fixed to shaft 205 and flexible cover 235 may have
proximal and distal ends sealingly fixed to support member ends
250, 255, respectively. Alternatively, in an embodiment not shown,
the proximal and distal ends of flexible cover 235 may be fixed
directly to catheter shaft 205 and both of support member ends 250,
255 may be slidably mounted along catheter shaft 205 within
flexible cover 235 between the cover ends. In this alternative
example, at least the cover proximal end is sealingly fixed to
shaft 205 by a sealed bond joint to prevent fluid flow there
through.
[0025] In the relaxed, expanded configuration of occluder 217 shown
in FIG. 2, support member 230 has a first length X. When struts 245
are radially compressed, support member ends 250 and 255 separate
to create a second length Y, as shown in FIG. 3. Second length Y is
longer than first length X. As described above, at least one of
support member ends 250, 255 slides freely along catheter shaft 205
to accommodate the dimensional changes between lengths X and Y.
[0026] Support member 230 may be constructed of a material having
sufficient resiliency to recover its original pre-formed shape
after struts 245 are temporarily compressed, and also having
sufficient resiliency to expand flexible covering 235 therewith.
Support member 230 may be made from a high-modulus thermoplastic or
thermo-set plastic, nitinol (TiNi), stainless steel or a
work-hardenable super alloy comprising nickel, cobalt, chromium and
molybdenum. Struts 245 of support member 230 are pre-formed in the
relaxed size and shape of occluder 217 by an appropriate process
selected from techniques such as casting, heat setting, molding,
stamping or thermoforming, depending on the type of material
chosen.
[0027] An exemplary method of using guiding catheter 100, 200 will
now be described. FIG. 4 illustrates guiding catheter 100, 200
positioned within patient's vascular system 400 for use with a
therapeutic device. The clinician manually squeezes resilient
occluder 117, 217 to a compressed configuration and inserts the
distal end of guiding catheter 100, 200 through introducer sheath
460 into vascular system 400, typically through a femoral artery in
the groin area. After exiting introducer sheath 460 into vascular
system 400, occluder 117, 217 will resiliently return to its normal
expanded size and shape. Guiding catheter 100, 200 is advanced
through aorta 465 until the distal end of the catheter is located
near the ostium of targeted branch artery 470. In the example
shown, branch artery 470 is a patient's left coronary artery.
[0028] When the distal end of guiding catheter 100, 200 is inserted
into the ostium of artery 470, resilient occluder 117, 217 is
squeezed, or wedged into sealing engagement with vessel wall 425,
thus occluding vessel lumen 420 proximal to stenosis 475, as shown
in FIG. 5. Preferably, the distal end of guiding catheter 100, 200
is inserted into artery 470 until major diameter 125 is beyond the
ostium to provide optimal sealing between occluder 117, 217 and
vessel wall 425. A therapeutic device, such as balloon dilatation
catheter 480, including a dilatation balloon, is advanced through
central lumen 120, 220 until the balloon reaches a desired position
within stenosis 475, as illustrated in FIG. 6. The dilatation
balloon is then inflated to dilate stenosis 475. Balloon dilatation
catheter 480 may then be removed, and blood may be aspirated from
lumen 420, including any debris released during the dilation of
stenosis 475. Aspiration may be performed either directly into
lumen 120, 220 of guiding catheter 100, 200 or, alternatively, into
aspiration catheter 402, which may be advanced to the treated area
within vessel lumen 420, as shown in FIG. 7. As will be recognized
by those of skill in the art, aspiration during proximal occlusion
of an artery requires retrograde blood flow in arterial lumen 420.
If retrograde flow through the capillary bed is insufficient to
support aspiration of the potentially contaminated blood, then
simultaneous flush and aspiration can be established through
aspiration catheter 402 and guiding catheter 100, 200. If used,
aspiration catheter 402 may be subsequently withdrawn from lumen
120, 220, as shown in FIG. 8. Lastly, guiding catheter 100, 200 is
withdrawn from vessel lumen 420.
[0029] While at least one exemplary embodiment has been presented
in the foregoing detailed description, it should be understood that
various changes can be made in the function and arrangement of
elements without departing from the scope of the invention as set
forth in the appended claims and the legal equivalents thereof.
* * * * *