U.S. patent application number 09/383585 was filed with the patent office on 2001-10-11 for catheter shaft with an oblong transverse cross-section.
Invention is credited to CAMPBELL, PATRICK K., FERNANDO, SR., JOVITO L., SIRHAN, MOTASIM M., THORNTON, TROY L., WASICEK, LAWRENCE D., WILLIAMS, ERIC.
Application Number | 20010029362 09/383585 |
Document ID | / |
Family ID | 27567634 |
Filed Date | 2001-10-11 |
United States Patent
Application |
20010029362 |
Kind Code |
A1 |
SIRHAN, MOTASIM M. ; et
al. |
October 11, 2001 |
CATHETER SHAFT WITH AN OBLONG TRANSVERSE CROSS-SECTION
Abstract
A balloon dilatation catheter having a catheter shaft with an
oblong transverse cross-section with one transverse dimension in a
first direction being significantly larger than a second transverse
dimension in a direction perpendicular to the first direction. The
first dimension is about 1.1 to about 3 times greater, preferably
about 1.2 to about 2.5 times greater than the second dimension. In
one embodiment, a length of the distal shaft section has inner and
outer tubular members where about 30% to not more than about 90% of
the inner periphery of the outer tubular member takes the shape of
and is secured to the exterior of the inner tubular member. In
another embodiment the flexible distal shaft section is an extruded
section having an oval or elliptical transverse cross-section.
Preferably a pseudoelastic hypotube of NiTi alloy defines at least
part of the inflation lumen within the catheter shaft. In another
embodiment of the invention the proximal shaft of the catheter has
an inner and outer tubular member.
Inventors: |
SIRHAN, MOTASIM M.;
(SUNNYVALE, CA) ; FERNANDO, SR., JOVITO L.;
(MODESTO, CA) ; THORNTON, TROY L.; (SAN FRANCISCO,
CA) ; CAMPBELL, PATRICK K.; (GEORGETOWN, MA) ;
WILLIAMS, ERIC; (FAIRFIELD, CA) ; WASICEK, LAWRENCE
D.; (SUNNYVALE, CA) |
Correspondence
Address: |
EDWARD J LYNCH
CROSBY HEAFEY ROACH & MAY
1999 HARRISON STREET
OAKLAND
CA
946042084
|
Family ID: |
27567634 |
Appl. No.: |
09/383585 |
Filed: |
August 25, 1999 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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09383585 |
Aug 25, 1999 |
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09063874 |
Apr 21, 1998 |
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6013069 |
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09063874 |
Apr 21, 1998 |
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08742689 |
Nov 4, 1996 |
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5743875 |
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08742689 |
Nov 4, 1996 |
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08368794 |
Jan 4, 1995 |
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08368794 |
Jan 4, 1995 |
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08250708 |
May 27, 1994 |
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08250708 |
May 27, 1994 |
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08021062 |
Apr 15, 1993 |
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08250708 |
May 27, 1994 |
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08192065 |
Feb 4, 1994 |
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5496275 |
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08192065 |
Feb 4, 1994 |
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08095814 |
Jul 20, 1993 |
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08095814 |
Jul 20, 1993 |
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07700617 |
May 15, 1991 |
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08095814 |
Jul 20, 1993 |
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07870820 |
Apr 20, 1992 |
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Current U.S.
Class: |
604/524 |
Current CPC
Class: |
A61M 25/0021 20130101;
A61M 25/0029 20130101; A61M 2025/0037 20130101; A61M 2025/0034
20130101; A61M 2025/1063 20130101; A61L 29/041 20130101; C08L 33/02
20130101; A61M 2025/0039 20130101; A61M 2025/0063 20130101; A61M
25/0009 20130101; A61L 29/041 20130101; A61M 25/0043 20130101; A61M
25/104 20130101; A61M 2025/0183 20130101; A61M 2025/0004 20130101;
A61M 2025/0177 20130101; A61M 2025/1097 20130101; A61M 25/0023
20130101 |
Class at
Publication: |
604/524 |
International
Class: |
A61M 025/00 |
Claims
What is claimed is:
1. An elongated dilatation catheter for performing an angioplasty
procedure, comprising: a) an elongated catheter shaft having
proximal and distal ends, a guidewire receiving inner lumen
extending therein to a distal guidewire port in the distal end of
the catheter shaft and a inflation lumen extending therein to a
inflation port-spaced proximally of the distal end of the catheter
shaft; b) an inflatable dilatation member mounted proximal to the
distal end of the catheter shaft for performing an angioplasty
procedure which has an interior in fluid communication with
inflation lumen through the inflation port; and c) a flexible
catheter shaft section which is proximal to the inflatable
dilatation member, which has a length of at least about 4 cm and
which has an oblong transverse shape with a first transverse
dimension in a first direction substantially greater than a second
transverse dimension in a second direction perpendicular to the
first direction.
2. The dilatation catheter of claim 1 wherein the first transverse
dimension is at least 1.1 but not more than 3 times greater than
the second transverse dimension.
3. The dilatation catheter of claim 1 wherein the first transverse
dimension is at least about 1.2 to about 2.5 times greater than the
second dimension.
4. The dilatation catheter of claim 1 wherein the first transverse
dimension is at least 0.003 inch greater than the second transverse
dimension.
5. The dilatation catheter of claim 1 wherein the first transverse
dimension is at least 0.05 inch greater than the second transverse
dimension.
6. The dilatation catheter of claim 1 wherein the catheter shaft
proximal to the inflatable dilatation member has an elliptical or
oviform transverse cross-sectional shape.
7. The dilatation catheter of claim 1 wherein the catheter shaft
section having an oblong transverse shape is not more than about 40
cm in length.
8. The dilatation catheter of claim 1 wherein the proximal catheter
shaft section has an oblong transverse cross-sectional shape.
9. The dilatation catheter of claim 1 wherein a proximal guidewire
port is spaced a short distance proximally from the inflatable
dilatation member and a substantial distance from the proximal end
of the catheter and is in communication with the guidewire
receiving inner lumen.
10. The dilatation catheter of claim 9 wherein at least one
perfusion port extends through the flexible distal shaft section
proximal to the inflatable dilatation member and distal to the
proximal guidewire port and is in fluid communication with the
guidewire receiving inner lumen.
11. The dilatation catheter of claim 1 wherein at least one
perfusion port is provided in the flexible distal shaft section
distal to the inflatable dilatation member which is in fluid
communication with the guidewire receiving inner lumen.
12. The dilatation catheter of claim 1 wherein the catheter has a
proximal section formed at least in part of metal hypotubing having
an inner lumen in fluid communication with the inflation lumen in
the flexible distal section of the catheter shaft.
13. The dilatation catheter of claim 11 wherein the metal
hypotubing is formed of a metallic alloy selected from the
group-consisting of stainless steel and NiTi alloys.
14. The dilatation catheter of claim 12 wherein the alloy is a NiTi
alloy having pseudoelastic characteristics.
15. The dilatation catheter of claim 1 wherein the flexible distal
catheter shaft section includes an inner tubular member having a
passageway therethrough which defines the guidewire receiving inner
lumen, and an outer tubular member disposed about the inner tubular
member with at least about 30% but not more than about 90% of the
inner periphery thereof taking the shape of and being secured to
the exterior of the inner tubular member along, a length thereof
and with a portion of the inner periphery of the outer tubular
member being unsecured to the exterior of the inner tubular member
with the inner inflation lumen extending along the length between
the inner and outer tubular members.
16. The dilatation catheter of claim 15 wherein not more than 80%
of the inner periphery of the outer tubular member along said
length is secured to the exterior of the inner tubular member.
17. The dilatation catheter of claim 15 wherein the outer tubular
member is secured to inner tubular member in the flexible distal
catheter shaft section by a heat bond or an adhesive bond.
18. The dilatation catheter of claim 15 wherein the outer tubular
member has been heat shrunk onto the inner tubular member.
19. The dilatation catheter of claim 15 wherein a proximal
guidewire port is provided through a wall of the flexible distal
section which is spaced a short distance proximally from the
inflatable dilatation member and a substantial distance from the
proximal end of the catheter shaft and which is in fluid
communication with the guidewire receiving inner lumen.
20. The dilatation catheter of claim 19 wherein at least one
perfusion port extends through a wall of the flexible distal shaft
section proximal to the inflatable dilatation member and distal to
the proximal guidewire port where the outer tubular member takes
the shape of and is secured to the inner tubular member and is in
fluid communication with the guidewire receiving inner lumen.
21. The dilatation catheter of claim 19 wherein a slit extends
distally from the proximal guidewire port through a portion of the
flexible distal section in communication with the guidewire
receiving inner lumen.
22. The dilatation catheter of claim 21 wherein a supporting tube
is disposed within the inflation lumen to prevent the expansion
thereof.
23. The dilatation catheter of claim 1 including a hypotube
extending within the catheter shaft defining at least a proximal
section of the catheter shaft.
24. The dilatation catheter of claim 23 wherein the hypotube is
formed of a psuedoelastic NiTi alloy having a stable austenite
phase at body temperature.
25. The dilatation catheter of claim 15 wherein the length of the
outer tubular member which takes the shape of and is secured to the
inner tubal member is at least about 4 cm but not more than about
40 cm.
26. An elongated dilatation catheter for performing an angioplasty
procedure, comprising: a) an elongated catheter shaft having
proximal and distal ends, a guidewire receiving inner lumen
extending therein to a distal guidewire port in the distal end of
the catheter shaft and a inflation lumen extending therein to a
inflation port spaced proximally of the distal end of the catheter
shaft; b) an inflatable dilatation member mounted proximal to the
distal end of the catheter shaft for performing an angioplasty
procedure which has an interior in fluid communication with
inflation lumen through the inflation port; and c) a high-strength
tubular member which extends through the proximal shaft section
from an adaptor on the proximal end of the catheter shaft and which
defines the inflation lumen extending therein.
27. The elongated dilation catheter of claim 26 wherein the
hypotube is formed of a pseudoelastic NiTi alloy having a stable
austenite phase at body temperature.
28. The elongated dilatation catheter of claim 26 wherein the
proximal shaft section has on oblong transverse cross-sectional
shape.
29. An elongated intravascular catheter for performing a
therapeutic or diagnostic procedure, comprising: a) an elongated
catheter shaft having proximal and distal ends, a length of at
least 90 cm, a distal guidewire port in the distal end of the
catheter shaft, a first inner lumen extending to the distal
guidewire port which is configured to slidably receive a guidewire
therein and a second inner lumen extending from the proximal end to
a location spaced proximally from the distal end; and b) a flexible
catheter shaft section which has a length of at least about 4 cm
and which has a first transverse dimension in a first direction
substantially larger than a second transverse dimension in a second
direction perpendicular to the first direction.
30. The intravascular catheter of claim 29 wherein the first
transverse dimension is at least 1.1 but not more than 3 times
larger than the second transverse dimension.
31. The intravascular catheter of claim 29 wherein the first
transverse dimension is at least about 1.2 to about 2.5 times
larger than the second transverse dimension.
32. The intravascular catheter of claim 29 wherein the first
transverse dimension is at least 0.003 inch larger than the second
transverse dimension.
33. The intravascular catheter of claim 29 wherein the first
transverse dimension is at least 0.005 inch larger than the second
transverse dimension.
34. The intravascular catheter of claim 29 wherein the catheter
shaft section has an elliptical or oviform transverse
cross-sectional shape.
35. The intravascular catheter of claim 29 wherein the catheter
shaft has a proximal guidewire port spaced a short distance
proximally from the distal end of the catheter and a substantial
distance from the proximal end of the catheter and is in
communication with the first inner lumen.
36. The intravascular catheter of claim 35 wherein the proximal
guidewire port is spaced about 5 to about 40 cm from the distal end
of the shaft.
37. The intravascular catheter of claim 35 wherein the proximal
guidewire port is spaced about 10 to about 30 cm from the distal
end of the shaft.
38. The intravascular catheter of claim 29 wherein the catheter has
a proximal section formed at least in part of metal hypotubing
having an inner lumen in fluid communication with the second inner
lumen in the flexible distal section of the catheter shaft.
39. The intravascular catheter of claim 38 wherein the metal
hypotubing is formed of a metallic alloy selected from the group
consisting of stainless steel and NiTi alloys.
40. The intravascular catheter of claim 39 wherein the alloy is a
NiTi alloy having pseudoelastic characteristics.
41. The intravascular catheter of claim 29 wherein the flexible
catheter shaft section includes an inner tubular member having a
passageway therethrough which defines the guidewire receiving inner
lumen, and an outer tubular member disposed about the inner tubular
member with at least about 30% but not more than about 90% of the
inner periphery thereof taking the shape of and being secured to
the exterior of the inner tubular member along a length thereof and
with a portion of the inner periphery of the outer tubular member
being unsecured to the exterior of the inner tubular member with
the second inner lumen extending along the length between the inner
and outer tubular members.
42. The intravascular catheter of claim 39 wherein the outer
tubular member is heat shrunk onto the inner tubular member.
43. The intravascular catheter of claim 39 wherein a proximal
guidewire port is provided through a wall of the flexible distal
section which is spaced a short distance proximally from the distal
end of the catheter shaft and a substantial distance from the
proximal end of the catheter shaft and which is in fluid
communication with the guidewire receiving inner lumen.
44. The intravascular catheter of claim 43 wherein the proximal
guidewire port is spaced not more than about 40 cm from the distal
end of the catheter shaft.
45. The intravascular catheter of claim 43 wherein the proximal
guidewire port is spaced about 10 to about 30 cm from the distal
end of the catheter shaft.
46. The intravascular catheter of claim 29 wherein a slit extends
distally from the proximal guidewire port through a portion of the
flexible distal section in communication with the guidewire
receiving inner lumen.
47. A balloon dilatation catheter for performing an angioplasty
procedure, comprising: a) an elongated catheter shaft having
proximal and distal ends, a guidewire port in the distal end, a
guidewire receiving inner lumen extending therein to the distal
guidewire port, an inflation port spaced proximally from the distal
end and a inflation lumen extending therein to the inflation port;
b) an inflatable dilatation member mounted proximal to the distal
end of the catheter shaft which has an interior in fluid
communication with the inflation lumen through the inflation port;
c) a proximal catheter shaft section having an inner tubular member
which defines the guidewire receiving inner lumen in the proximal
shaft section and an outer tubular member disposed about the inner
tubular member and defining between the inner and outer tubular
members the inflation lumen within the proximal shaft section; and
d) a flexible distal catheter shaft section distal to the proximal
catheter shaft section having a length of at least about 4 cm in
which a first transverse dimension in a first direction is
substantially greater than a second transverse dimension in a
second direction perpendicular to the first direction along said
length, a first inner lumen forming the guidewire receiving inner
lumen within this catheter shaft section and a second inner lumen
forming the inflation lumen within this catheter shaft section.
48. The dilatation catheter of claim 47 wherein the first
transverse dimension is at least 1.1 but not more than 3 times
greater than the second transverse dimension.
49. The dilatation catheter of claim 47 wherein the first
transverse dimension is at least about 1.2 to about 2.5 times
greater than the second dimension.
50. The dilatation catheter of claim 47 wherein the first dimension
is at least 0.003 inch greater than the second dimension.
51. The dilatation catheter of claim 47 wherein the first dimension
is at least 0.005 inch greater than the second dimension.
52. The dilatation catheter of claim 47 wherein the catheter shaft
proximal to the inflatable dilatation member has an elliptical or
oviform transverse cross-sectional shape.
53. The dilatation catheter of claim 47 wherein a proximal
guidewire port is spaced a short distance proximally from the
inflatable dilatation member and a substantial distance from the
proximal end of the catheter and is in communication with the
guidewire receiving inner lumen.
54. The dilatation catheter of claim 53 wherein the proximal
guidewire port is spaced about 5 to about 40 cm from the distal end
of the shaft.
55. The dilatation catheter of claim 53 wherein the proximal
guidewire port is spaced about 10 to about 30 cm from the distal
end of the shaft.
56. The dilatation catheter of claim 53 wherein at least one
perfusion port extends through the flexible distal shaft section
proximal to the inflatable dilatation member and distal to the
proximal guidewire port and is in fluid communication with the
guidewire receiving inner lumen.
57. The dilatation catheter of claim 47 wherein at least one
perfusion port is provided in the flexible distal shaft section
distal to the inflatable dilatation member which is in fluid
communication with the guidewire receiving inner lumen.
58. The dilatation catheter of claim 47 wherein the catheter has a
proximal section formed at least in part of metal hypotubing having
an inner lumen in fluid communication with the inflation lumen in
the flexible distal section of the catheter shaft.
59. The dilatation catheter of claim 58 wherein the metal
hypotubing is formed of a metallic alloy selected from the group
consisting of stainless steel and NiTi alloys.
60. The dilatation catheter of claim 59 wherein the alloy Is a NiTi
alloy having superelastic characteristics.
Description
RELATED APPLICATIONS
[0001] This application is a continuation-in-part of copending
application Ser. No. 08/250,708, filed on May 27, 1994, which is a
continuation-in-part of copending application Ser. No. 08/021,062,
filed on Apr. 15, 1993, and Ser. No. 08/192,065, filed on Feb. 4,
1994, the latter application being a continuation of Ser. No.
08/095,814, filed on Jul. 20, 1993, entitled LOW PROFILE DILATION
CATHETER, which is a continuation-in-part of Ser. No. 07/700,617,
filed on May 5, 1991, entitled LOW PROFILE DILATION CATHETER, and
is a continuation-in-part of Ser. No. 07/870,820, filed on Apr. 20,
1992, entitled LOW PROFILE DILATION CATHETER.
BACKGROUND OF THE INVENTION
[0002] This invention generally relates to intravascular catheters,
such as balloon dilatation catheters used in percutaneous
transluminal coronary angioplasty (PTCA).
[0003] PTCA is a widely used procedure for the treatment of
coronary heart disease wherein a balloon dilatation catheter is
advanced into the patient's coronary artery and the balloon on the
distal portion of the catheter is inflated within the stenotic
region of the patient's artery to open up the arterial passageway
and thereby increase the blood flow therethrough. To facilitate the
advancement of the dilatation catheter into the patient's coronary
artery, a guiding catheter having a preshaped distal tip is first
percutaneously introduced into the cardiovascular system of a
patient by the Seldinger technique through the brachial or femoral
arteries and is advanced therein until the preshaped distal tip of
the guiding catheter is disposed within the aorta adjacent the
ostium of the desired coronary artery. The guiding catheter is
twisted or torqued from its proximal end, which extends out of the
patient, to guide the distal tip of the guiding catheter into the
desired ostium. A balloon dilatation catheter may then be advanced
through the inner lumen of the guiding catheter into the patient's
coronary artery until the balloon an the dilatation catheter is
disposed within the stenotic region of the patient's artery. The
balloon is inflated and deflated one or more times to open up the
arterial passageway and increase the flow of blood.
[0004] One type of catheter frequently used in PTCA procedures is
an over-the-wire type balloon dilatation catheter. Commercially
available over-the-wire type dilatation catheters include the
SIMPSON ULTRA LOW PROFILE (TM), the HARTZLER ACX (R), the HARTZLER
ACX II (TM), the PINKERTON 0.018 (TM) and the ACS TEN (TM) balloon
dilatation catheters sold by the assignee of the present invention,
Advanced Cardiovascular Systems, Inc. (ACS).
[0005] Another type of over-the-wire dilatation catheter is the
rapid exchange type catheter, which was introduced by ACS under the
trademark ACS RX.RTM. Coronary Dilatation Catheter. It is described
and claimed in U.S. Pat. No. 5,040,548 (Yock), U.S. Pat. No.
5,061,273 (Yock), U.S. Pat. No. 4,748,982 (Horzewski et al.) and
U.S. Pat. No. 5,154,725 (Leopold) which are incorporated herein by
reference. This dilatation catheter has a short guidewire receiving
sleeve or inner lumen extending through a distal portion of the
catheter. The sleeve or inner lumen extends proximally from a first
guidewire port in the distal end of the catheter to a second
guidewire port in the catheter spaced proximally from the
inflatable member of the catheter. A slit may be provided in the
wall of the catheter body which extends distally from the second
guidewire port, preferably to a location proximal to the proximal
end of the inflatable balloon. The structure of the catheter allows
for the rapid exchange of the catheter without the need for an
exchange wire or adding a guidewire extension to the proximal end
of the guidewire.
[0006] Some over-the-wire and rapid exchange type dilatation
catheters have perfusion capabilities where one or more perfusion
ports are provided in the catheter shaft proximal to the dilatation
balloon which are in fluid communication with a guidewire receiving
inner lumen extending to the distal end of the catheter.
Additionally, one or more perfusion ports are preferably provided
in the catheter shaft, distal to the balloon which are also in
fluid communication with the guidewire receiving inner lumen. When
the balloon of a dilatation catheter with perfusion capabilities is
inflated to dilate a stenosis, oxygenated blood in the artery or
the aorta or both, depending upon the location of the proximal
perfusion parts of the dilatation catheter within the coronary
anatomy, is forced to pass through the proximal perfusion ports,
through the guidewire receiving inner lumen of the catheter and out
the distal perfusion ports. The flow of oxygenated blood downstream
from the inflated balloon minimizes ischemic conditions in tissue
distal to the balloon and allows for long term dilatations, e.g. 30
minutes or even several hours or more. Commercially available
perfusion type dilatation catheters include the STACK PERFUSION
(TM) and the ACS RX PERFUSION (TM) dilatation catheters which are
sold by ACS.
[0007] A continual effort has been made in the development of
intravascular catheters, particularly angioplasty catheters, to
reduce the transverse dimensions or profile of such catheters and
the flexibility without detrimentally affecting the pushability and
other characteristics of the catheters, particularly in the distal
portion of the catheters which are advanced through tortuous
anatomy. A balloon dilatation catheter with an increased
flexibility and an increased pushability allow the catheter to be
advanced much further into a patient's vasculature and to cross
much tighter lesions.
[0008] Despite the many technical advances in these areas, the need
for intravascular catheters having even greater flexibility and
pushability remains. The present invention satisfies these and
other needs.
SUMMARY OF THE INVENTION
[0009] The present invention is directed to an elongated
intravascular catheter with improved flexibility and pushability,
particularly in the distal portion thereof.
[0010] The, catheter shaft of the invention has, at least in the
distal portion thereof, an oblong transverse cross-section wherein
the transverse dimension in a first direction is larger than the
transverse dimension in a second direction perpendicular to the
first direction. In a presently preferred embodiment the larger
transverse dimension is about 1.1 to about 3 times, preferably
about 1.2 to about 2.5 times, greater than the smaller
perpendicular transverse dimension. For dilatation catheters
suitable for coronary arteries the differential between the first
and second transverse dimensions is at least about 0.003 inch
(0.076 mm) and for dilatation catheters for peripheral use this
differential should be at least about 0.005 inch (0.127 mm). The
shape of the oblong transverse cross-section proximal to the
balloon is preferably oviform or elliptical in nature. The length
of the oblong portion of the catheter shaft is at least about 4
cm., preferably at least about 7 cm. The entire length of the
catheter shaft may have the desired oblong transverse cross-section
or only the portion of the catheter which extends out of the
guiding catheter, e.g. about 10 to about 40 cm. Advantages have
also been recognized with the proximal portion of the catheter
shaft having an oblong transverse cross-section in accordance with
this invention.
[0011] In one embodiment the intravascular catheter of the
invention generally includes, at least in the distal portion
thereof, an inner tubular member having an inner lumen extending
therein and an outer tubular member disposed about the inner
tubular member with at least about 30% and not more than about 90%,
preferably not more than about 80%, of the inner periphery of the
outer tubular member taking the shape of and being secured to
exterior of the inner tubular member along a length of the catheter
shaft of at least about 4 cm, preferably at least about 7 cm. An
inner inflation lumen extends along the secured length between the
portion of the outer tubular member which does not take the shape
of and which is not secured to the underlying inner tubular member.
The bond between the secured inner and outer tubular member need
not be continuous. It may be intermittent, so long as a significant
portion of the interface between the two members is secured along
the length. The inner and outer tubular members may be secured
together by heat or laser bonding, adhesive bonding, heat shrinking
the outer tube onto the inner tube or other suitable means.
[0012] By securing a length of the outer tubular member in the
distal portion of the catheter to the exterior of the inner member,
the profile of the catheter body in at least one transverse
dimension in that area is reduced substantially to thereby provide
improved flexibility. Moreover, the secured portions of the inner
tubular member and the outer tubular member support one another
thereby providing improved pushability. Substantial reductions in
only one transverse dimension can provide substantial improvements
in flexibility. Minimum cross-sectional dimensions of the small
diameter section of the outer tubular member for coronary
dilatation catheters are on the order of about 0.01 to about 0.06
inch (0.51-1.5 mm). For peripheral arteries this dimension may be
larger.
[0013] The improvements of the invention are applicable to a wide
range of elongated intravascular catheters which are at least 90 cm
in length and which are percutaneously introduced and advanced deep
within the patient's vascular system, such as in the coronary
anatomy. It is particularly suitable in essentially all types of
dilatation catheters with inflatable or expandable dilatation
members on their distal extremities, such as those described in the
patents incorporated herein by reference. These and other
advantages of the invention will become more apparent from the
following detailed description of the invention when taken in
conjunction with accompanying exemplary drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is an elevational view, partially in section, of a
balloon dilatation catheter embodying features of the
invention.
[0015] FIG. 2 is a transverse cross-sectional view of the catheter
shown in FIG. 1 taken along the lines 2-2.
[0016] FIG. 3 is a transverse cross-sectional view of the catheter
shown in FIG. 1 taken along the lines 3-3.
[0017] FIG. 4 is a transverse cross-sectional view of the catheter
shown in FIG. 1 taken along the lines 4-4.
[0018] FIG. 5 is a transverse cross-sectional view of the catheter
shown in FIG. 1 taken along the lines 5-5.
[0019] FIG. 6 is an elevational view, partially in section, of
another dilatation catheter embodying features of the
invention.
[0020] FIG. 7 is transverse cross-sectional view of the catheter
shown in FIG. 6 taken along the lines 7-7.
[0021] FIG. 8 is a transverse cross-sectional view of the catheter
shown in FIG. 6 taken along the lines 8-8.
[0022] FIG. 9 is a transverse cross-sectional view of the catheter
shown in FIG. 6 taken along the lines 9-9.
[0023] FIG. 10 is a transverse cross-sectional view of the catheter
shown in FIG. 6 taken along the lines 10-10.
[0024] FIG. 11 is an elevational view, partially in section, of
another dilatation catheter embodying features of the
invention.
[0025] FIG. 12 is a transverse cross-sectional view of the catheter
shown in FIG. 11 taken along the lines 12-12.
[0026] FIG. 13 is a transverse cross-sectional view of the catheter
shown in FIG. 11 taken along the lines 13-13.
[0027] FIG. 14 is a transverse cross-sectional view of the catheter
shown in FIG. 11 taken along the lines 14-14.
[0028] FIG. 15 is a transverse cross-sectional view of the catheter
shown in FIG. 11 taken along the lines 15-15.
[0029] FIG. 16 is an elevational view, partially in section, of an
alternative embodiment of the invention wherein a supporting tube
is provided between the unsecured portion of the outer tubular
member and the inner tubular member.
[0030] FIG. 17 is a cross-sectional view of the catheter shown in
FIG. 16 taken along the lines 17-17.
[0031] FIG. 18 is a cross-sectional view of a catheter shaft of
another embodiment of invention wherein there are two unsecured
lengths of the outer tubular which define lumens with the
underlying inner tubular member.
[0032] FIG. 19 is an elevational view, partially in section, of
another embodiment of the invention in which the catheter shaft
proximal to the balloon has the desired transverse cross-sectional
dimensions and a hypotube formed of pseudoelastic NiTi alloy
supports the inflation lumen to prevent kinking.
[0033] FIG. 20 is a transverse cross-sectional view of the
embodiment shown in FIG. 19 taken along the lines 20-20.
[0034] FIG. 21 is a partial elevational view, particularly in
section, of a rapid exchange version of the catheter shaft shown in
FIGS. 19-20.
[0035] FIG. 22 is a elevational view, partially in section, of an
alternative embodiment of an over-the-wire dilatation catheter.
[0036] FIG. 23 is a transverse cross-sectional view of the
embodiment shown in FIG. 22 taken along the lines 23-23.
[0037] FIG. 24 is a transverse cross-sectional view of the
embodiment shown in FIG. 22 taken along the lines of 24-24.
DETAILED DESCRIPTION OF THE INVENTION
[0038] FIGS. 1-5 schematically illustrate an over-the-wire
dilatation catheter 10 embodying features of the invention. The
catheter 10 includes an elongated catheter shaft 11 which has an
inner tubular member 12, an outer tubular member 13 disposed about
the inner tubular member and an adapter 14 secured to the proximal
ends of the inner and outer tubular members. A relatively
inelastic, inflatable balloon 15 which is integral with the outer
tubular member 13 and a distal skirt 17 which is secured to the
distal end of the inner tubular member 12. Alternatively, the
balloon 15 may be formed from different material and be secured to
the outer tubular member 13.
[0039] As shown in FIGS. 1 and 3, the distal portion of the outer
tubular member 13 in part takes the shape of and is secured to the
exterior of the inner tubular member 12 along the length 18. The
unsecured portion 20 of the outer tubular member 13 along the
length 18 forms with the inner tubular member 12 an inflation lumen
21 which is in fluid communication with the interior of the balloon
15. The inner lumen 22 of the inner tubular member 12 extends
parallel to the inflation lumen 21 along the length 18. As best
shown in FIG. 3, the transverse dimension of the catheter shaft 11
along the length 18 in the vertical direction is substantially
larger than the transverse dimension of the catheter shaft in the
horizontal direction along said length.
[0040] The proximal portion of the catheter shaft 11, as shown in
FIGS. 1-3, is conventional where the outer tubular member 13 is
disposed about but is unsecured to the inner tubular member 12 and
defines with the inner tubular member an annular inflation lumen 23
which is in fluid communication with the inflation lumen 21 in the
distal portion of the catheter shaft.
[0041] The use of the dilatation catheter shown in FIGS. 1-5
generally may follow conventional PTCA practices with over-the-wire
type dilatation catheters. A guidewire 24 is backloaded into the
inner lumen 22 of the inner tubular member 12 and both the
guidewire and the catheter 10 are advanced together through a
guiding catheter (not shown) which has been previously disposed
within the patient's arterial system, with the distal end of the
guiding catheter seated within the ostium of the desired coronary
artery. The guidewire 24 is advanced out the distal end of the
guiding catheter into the patient's coronary anatomy until it
crosses the lesion to be dilated, and then the dilatation catheter
10 is advanced over the guidewire which is being herd in position,
until the balloon 15 on the dilatation catheter is properly
disposed within the stenotic region, so that the lesion can be
dilated upon one or more inflations of the balloon. After the
dilatation, the balloon 15 is deflated and the catheter 10 and the
guidewire 24 may be withdrawn from the patient. If further
treatment or diagnosis is to be conducted, the guidewire 24 can be
replaced with an exchange wire before removing the dilatation
catheter so that the first catheter can be removed and another
advanced into the desired location or an extension wire can be
attached to the proximal end of the guidewire in place which
extends out of the patient to perform essentially the same
function. See the discussion of exchange wires and extension wires
in U.S. Pat. No. 4,827,941 (Taylor et al.) which has been
incorporated herein by reference.
[0042] FIGS. 6-10 schematically illustrate another dilatation
catheter 30 embodying features of the invention which is configured
for rapid exchange. The structure of the most distal portion of the
catheter shaft 31 is quite similar to the embodiment shown in FIGS.
1-5 in that the distal section of the catheter shaft 31 includes an
outer tubular member 32 which is disposed about an inner tubular
member 33 and which in part takes the shape of and is secured to
the exterior of the inner tubular member along a length 34 of the
distal shaft. An unsecured portion 35 of the outer tubular member
32 forms an inflation lumen 36 which is in fluid communication with
the relatively inelastic balloon 37. In this embodiment, the outer
tabular member 32 and the balloon 37 are formed in a unitary
construction. The distal skirt 38 of the balloon 37 is secured to
the distal end of the inner tubular member 33.
[0043] Guidewire receiving inner lumen 40 extends proximally within
the inner tubular member 33 from a distal guidewire port 41 in the
distal end of the inner tubular member to a proximal guidewire port
42. A guidewire 43 is slidably disposed within the inner lumen 40
and extends out both the distal port 41 and the proximal port 42. A
slit 44 is provided in the secured sections of the inner and outer
tubular members 33 and 32 respectively and it extends distally from
the proximal guidewire port 42 to a location 45 proximal to the
balloon 37 to facilitate separation of the guidewire 43 and the
catheter shaft 31 when replacing catheter 30 with another catheter
as described in U.S. Pat. No. 4,748,982 (Horzewski et al.) which is
incorporate herein by reference. The proximal guidewire port 42 is
located at least about 5 cm but not more than about 45 cm from the
distal end of the catheter.
[0044] The proximal portion of the catheter shaft 31 has a high
strength inner tubular member 46, e.g. hypotubing, with a tightly
fitting outer plastic jacket or coating 47. An adapter 48 is
secured to the proximal end of the catheter shaft 31 to direct
inflation fluid through the inner lumen 50 in the high strength
tubular member 46 and the inflate lumen 36 between the inner
tubular member 33 and the unsecured portion of the outer tubular
member 32 to the interior of balloon 37. The distal extremity 51 of
the high strength tubular member 46 is tapered to facilitate
extension into the proximal end of the inflation lumen 36 where it
is secured by suitable means such as an adhesive or by heat
shrinking the proximal end of the outer tubular member about the
tapered extremity 51. The high strength tubular member may be
formed of stainless steel or a NiTi alloy, particularly a NiTi
alloy with pseudoelastic properties, such as described in
co-pending application Ser. No. 07/629,381, filed Dec. 18, 1990;
Ser. No. 07/994,679, filed Dec. 22, 1992 and Ser. No. 08/212,431,
filed Mar. 11, 1994, assigned to the present assignee, Advanced
Cardiovascular Systems, Inc. which are incorporated herein by
reference. A dual lumen type construction such as described in
Horzewski et al. above may be used in the portion of the catheter
shaft 31 proximal to the proximal guidewire port 42.
[0045] There are at least two modes of inserting the dilatation
catheter 30 of this embodiment into the patient's coronary anatomy.
The first method is for the most part the same as in the prior
embodiment, namely, the guidewire 43 is preloaded into the short
guidewire receiving inner lumen 40 of the inner tubular member 33
and both are advanced through a guiding catheter (not shown)
previously disposed within the patient's arterial system with the
distal end of the guiding catheter seated within the ostium of a
coronary artery. The second mode, frequently called the "bare wire"
technique, involves first advancing a guidewire 43 through and out
the guiding catheter until the distal extremity of the guidewire is
positioned within the patient's coronary artery across the lesion
to be dilated. The proximal end of the guidewire 43, which is
outside the patient, is backloaded, i.e. inserted into the short
inner lumen 40 of the inner tubular member 33 and advanced
proximally therein until it exits the guidewire port 42. The
proximal end of the guidewire 43 is held in place and the catheter
30 is advanced over the guidewire through the patient's vascular
system until the dilatation balloon 37 on the catheter is
positioned across the stenotic region. The stenosis is dilated upon
the inflation of the balloon 37, and, after the dilatation of the
lesion, the balloon is deflated and the catheter is removed from
the patient's artery. If other treatments are necessary, the
catheter 30 is slidably withdrawn over the guidewire 43, leaving
the guidewire in place so that other catheters can be advanced over
the in-place guidewire in a similar manner without the need for
exchange wires or guidewire extensions, thereby significantly
reducing the overall time for the procedure.
[0046] FIGS. 11 through 15 illustrate yet another dilatation
catheter 60 embodying features of the invention which provides for
the perfusion of blood distal to the catheter during the dilatation
of a stenotic lesion. The catheter 60 includes the catheter shaft
61, an inner tubular member 62 which has an inner lumen 63, an
outer tubular member 64 disposed about the inner tubular member, an
adapter 65 secured to the proximal ends of the inner and outer
members, and a relatively inelastic balloon 66 which is secured by
its distal end to the distal end of the inner tubular member 62. A
portion of the outer tubular member 64 has a distal section 67 a
length 68 of which is secured to the exterior of the inner tubular
member 62 as previously described in the first two embodiments of
the invention. The above-described portion of this embodiment has
essentially the same structure as the embodiments shown in FIGS.
1-10.
[0047] The dilatation catheter shown in FIGS. 11-15 differs from
the other embodiments in that it has a plurality of perfusion ports
69 proximal to the balloon 66 which pass through the secured walls
of the inner and outer tubular members 62 and 64 respectively and
which are in fluid communication with the inner lumen 63 of the
inner tubular member 62. Additionally, one or more perfusion ports
70 are provided distal to the balloon 66 through the wall of the
inner tubular member 62 and are in fluid communication with the
inner lumen 63 extending therein. In this manner, when the balloon
66 is inflated during an angioplasty procedure within a patient's
vasculature, oxygenated blood is forced to pass through the
proximal perfusion ports 69, through the inner lumen 62 and then
out the distal perfusion ports 70 to provide oxygenated blood
distal to the catheter 60 and thereby avoid the generation of
ischemic conditions in downstream tissue. The transverse dimensions
of the inner tubular member 62 within the secured section are
preferably larger than in the embodiments previously discussed to
allow for an increased flow of blood.
[0048] The use of the embodiment shown in FIGS. 11-15 is
essentially the same as the embodiment shown in FIGS. 1-5. The only
essential difference is that the balloon 66 can be inflated for
significantly longer periods than the first described embodiments,
e.g. typically about 20-30 minutes but possibly up to 5 hours or
more, because oxygenated blood is continuously flowing to the
tissue distal to the inflated balloon.
[0049] The dilatation catheter 30 shown in FIGS. 6-10 may be
modified by providing a plurality of perfusion ports in the
catheter shaft as shown in FIGS. 11-15 distal to the proximal
guidewire port 42. However, the guidewire port 42 is preferably
spaced sufficiently far proximally from the portion of the secured
distal section having the perfusion ports so that the guidewire 43
can be pulled proximally and remain within the inner lumen 40 of
the inner tubular member 33 while the balloon is inflated during
a-long term dilatation but not interfere with the flow of blood
through the perfusion ports. After the angioplasty procedure is
completed, the guidewire 43 can then be advanced distally through
the inner lumen 40 and out the distal end thereof in order to
maintain access to the lesion in case further treatment or
diagnosis is necessary or desirable.
[0050] The above described catheters may be made by conventional
techniques well known to those skilled in the art. Many suitable
techniques are described in the references referred to herein. The
small diameter distal sections may be formed by heat shrinking the
portion of the outer tubular members which form the distal sections
onto the underlying inner tubular members with a mandrel disposed
in the space between the inner and outer tubular members so that
upon the heat shrinking of the outer tubular member an inflation
lumen is formed through the distal sections which is in fluid
communication with the lumen in the proximal portion of the
catheter body and the interior of the balloon. This bonds the small
dimensioned distal section to the inner tubular member. A mandrel
may also be inserted into the inner lumen of the inner tubular
member to support the latter during the heat shrinking of the outer
tubular member thereon to maintain its circularity. Alternate
methods may be employed to make the small dimensioned distal
section. For example, the small dimensioned distal section 17 may
be preformed and then be adhesively bonded to the exterior of the
inner tubular member. Multiple lumens similar to the inflation
lumen may be formed in the small dimensioned section, such as the
top and bottom thereof, by employing multiple mandrels when heat
shrinking the outer tubular member onto the exterior of the inner
tubular member.
[0051] With the embodiment of the invention shown in FIGS. 6-10
which have a slit 45 extending from the proximal guidewire port 42
through the secured portion of the catheter shaft 31 to facilitate
the separation of the catheter and the guidewire, there is a
tendency for the slit to open up when the fluid pressure within the
inflation lumen 36 is raised to high levels to inflate the balloon
37 for dilatation of stenoses. The opening of the slit allows the
guidewire to extend through the expanded or opened slit 44, but
upon deflation of the balloon the slit closes onto the guidewire 43
which precludes independent movement of the guidewire and catheter.
To avoid this problem, it is preferred to provide a support tube 71
to define the inner lumen 36 as shown in FIGS. 16 and 17 and to
prevent the expansion of the unsecured portion of the outer tubular
member 32. A filler 72 may be provided to eliminate voids between
the support tube 71 and the unsecured portion of the outer tubular
member 32. The support tube 71 may be formed of polyimide or other
high strength polymer materials or metals such as the previously
described pseudoelastic NiTi alloys. The catheter shown in FIGS. 16
and 17 is, except for the support tube 71 and filter 72,
essentially, the same as the catheter shown in FIGS. 6-10 and the
corresponding parts are numbered the same.
[0052] FIG. 18 is an alternative distal shaft construction wherein
an additional inner lumen 80 which can be used as an additional
inflation lumen to vent air or to deliver other fluids. In this
embodiment the additional lumen 80 should extend to the proximal
end of the catheter shaft so that fluid can be introduced into or
withdrawn from the additional lumen through an adapter mounted on
the proximal end. For delivery or withdrawal of inflation fluid the
lumen 80 should terminate within the interior of the inflatable
dilatation member. The lumen 80 should extend to the distal end of
the catheter to deliver fluids distal to the catheter.
[0053] FIGS. 19-20 illustrate an alternative embodiment of an
over-the-wire dilatation catheter 90 which has a flexible distal
shaft section 91, a stiffer proximal shaft section 92, an inflation
lumen 93 and a guidewire receiving lumen 94. A dilation balloon 95
is mounted on the distal shaft section 91 having an interior which
is in fluid communication with inflation lumen 93 through inflation
port 96. The inflation lumen 93 extends from the adaptor 97 to the
inflation port 96 through the proximal and distal shaft sections 92
and 91. An inflation lumen 93 and a guidewire receiving inner lumen
94 are stacked in the long direction of the transverse
cross-sectional profile as shown in FIG. 20. The proximal shaft
section 91 of the dilatation catheter 90 has a flexible hypotube 98
which defines the inflation lumen 93 as shown in FIG. 20 to prevent
the kinking of the inflation lumen when the catheter is advanced
through tortuous passageways. The hypotube 98 is preferably formed
of an alloy, such as pseudoelastic NiTi alloy, having an austenite
phase which is stable at body temperature and exhibiting a stressed
induced austenite-to-martinsite phase transformation. The hypotube
98 extends at least the length of the proximal section of the
catheter to a location proximal to the dilation balloon 95. Both
proximal and distal shaft sections 92 and 91 have eliptical
transverse cross-sections with the inflation lumen 93 and the
guidewire receiving lumen 94 being stacked in the long direction of
the transverse cross-sectional profile. The embodiment shown in
FIGS. 19-20 depict an over-the-wire version of the catheter 90 with
a guidewire 99 extending through the guidewire lumen 94 throughout
its entire length.
[0054] FIG. 21 illustrates a modification of the catheter 90 shown
in FIGS. 19-20 which is provided with a proximal guidewire port 100
in communication with the guidewire receiving lumen 94. A plug 101
may be provided in the guidewire receiving lumen 94 to urge the
proximal end of guidewire 100 when the latter is advanced
proximally through the guidewire lumen 94. If desired, the
guidewire lumen 94 and the adaptor 97 may be provided with a slit
102 such as described in U.S. Pat. No. 4,748,982 (Horzewski) and
U.S. Pat. No. 5,135,535 (Kramer) which are incorporated herein by
reference.
[0055] Another alternative embodiment of the invention is shown in
FIGS. 22-24 wherein the dilatation catheter 110 has a catheter
shaft 111 with a distal section 112 having an oblong transverse
cross-sectional shape and a proximal section 113 having an inner
tubular member 114 and an outer tubular member 115. The distal end
of the outer tubular member 115 is secured about the exterior of
the proximal end of the distal section 112 and the distal end of
the inner tubular member 114 is secured to a cylindrical extension
116 of the distal shaft section 112. The distal shaft section 112
preferably tapers to smaller dimensions at location 117 to increase
the flexibility of the distal most portion of the catheter shaft. A
guidewire receiving inner lumen 118 extends within the inner
tubular member 114 from the central arm 119 of the adapter 120 on
the proximal end of the catheter shaft 111 through the distal
section 112 to a guidewire port 121 in the distal end of the shaft.
An inflation lumen 122 extends from the second arm 123 of adapter
120 through the annular space between the inner and outer tubular
members 114 and 115, through the distal shaft section 112 into the
interior of the inflatable member 124.
[0056] The various components of the catheters and guidewires of
the invention can be formed from a wide variety of conventional
materials. The catheter shaft, including the inner and outer
tubular members may be made from polymeric materials such as
polyethylene, polyamide, polyvinyl chloride, polyester (e.g.
Hytrel.RTM. which is available from DuPont), polyetheretherketone
(e.g. Grade 381G from Victrex U.S.A.) and other suitable polymeric
materials. The hypotubing may be formed of stainless steel or NiTi
superelastic alloy material, such as described previously. The
balloon may be made from polyethylene, polyethylene terephthalate
and other relatively inelastic polymers and other materials.
[0057] The dimensions of the catheters generally follow the
dimensions of conventional intravascular catheters. For coronary
use the length is typically about 135 cm and the maximum outer
diameter of the outer tubular member is about 0.02 to about 0.06
inch (0.51-1.52 mm). The transverse shape of, the proximal section
of the catheter shaft may be circular, oviform or elliptical.
[0058] While the invention has been described herein primarily in
terms of certain preferred embodiments, the invention may be
employed in a wide variety of embodiments. Additionally,
modifications and improvements can be made to the invention without
departing from the scope thereof. Although individual features of
embodiments of the invention may be shown in some of the drawings
and not in others, those skilled in the art will recognize that
individual features of-one embodiment of the invention can be
combined with any or all the features of another embodiment.
* * * * *