AU2007200632A1

AU2007200632A1 - A catheter

Info

Publication number: AU2007200632A1
Application number: AU2007200632A
Authority: AU
Inventors: Ranier Betelia; Hung Van Vo
Original assignee: Gore Enterprise Holdings Inc
Current assignee: WL Gore and Associates Inc
Priority date: 2002-06-27
Filing date: 2007-02-14
Publication date: 2007-03-15
Anticipated expiration: 2023-06-25
Also published as: AU2007200632B2; AU2010202027B2; AU2010202028A1; AU2010202027A1; AU2010202028B2

Description

GO

GRIFFITH HACK PATENT AND TRADE MARK ATTORNEYS

SPECIFICATION

OF

PATENT APPLICATION

COUNTRY

TYPE

AUSTRALIA

Patent A CATHETER TITLE APPLICANT(S) GORE ENTERPRISE HOLDINGS, INC.

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION Standard Patent Applicant(s): GORE ENTERPRISE HOLDINGS, INC.

Invention Title: A CATHETER The following statement is a full description of this invention, including the best method for performing it known to me/us: 2 A CATHETER Field of the Invention This invention relates to apparatus and methods for removing emboli during vascular interventions. More particularly, the apparatus and methods of the present invention provide a catheter having an occlusion balloon of uniform thickness that facilitates retrograde flow and removes emboli from a treatment vessel via a funnelshaped taper of the occlusion balloon.

Background of the Invention Today there is a growing need to provide controlled access and vessel management during such procedures as stenting, atherectomy and angioplasty. Generally during these procedures there is a high opportunity for the release of embolic material. The emboli may travel downstream from the occlusion, lodging deep within the vascular bed and causing ischemia. The resulting ischemia may pose a serious threat to the health or life of a patient if the blockage forms in a critical area, such as the heart, lungs, or brain.

Several previously known apparatus and methods attempt to remove emboli formed during endovascular procedures by aspirating the emboli out of the vessel of interest using a catheter having an occlusion balloon. These previously known occlusion balloons, however, have various drawbacks, including variability in deployment of the balloon to the desired shape, inefficiency in removing emboli, and/or high cost and complicated processes associated with manufacturing the balloon.

In applicant's co-pending U. S. patent application Serial No. 09/418,727, filed October 15, 1999, which is incorporated herein by reference in its entirety, applicant describes the use of a bell or pear-shaped N \Mebourne\Cass\Paent\55DOOO55999\P5482AU I\Specis\P55482 AU I Specification 2007-2-14doc 14/02/07 3 occlusion balloon disposed on the distal end of an arterial catheter. The occlusion balloon comprises a compliant material having a variable thickness along its length to provide a bell-shape when inflated. The balloon is affixed to distal end of the catheter so that a distal portion of the balloon extends beyond the distal end of the catheter to provide an atraumatic tip or bumper for the catheter.

The balloon of that catheter may be formed using previously known techniques, such as varying the thickness of the balloon wall to achieve the preferred bell-shape in the deployed position. Such processes, however, can lead to variability in the final product due to the manufacturing process. Because variable thickness balloons present greater difficulties during manufacture than balloons having uniform wall thickness, the cost of such balloons may be higher.

In view of the foregoing limitations of previously known devices, it would be desirable to provide an apparatus for removing emboli from a vessel comprising an occlusion balloon of uniform thickness to enhance manufacturability of the occlusion balloon.

It also would be desirable to provide an apparatus for removing emboli from a vessel comprising an occlusion balloon of uniform thickness to reduce manufacturing cost and enhance product yield.

It further would be desirable to provide an apparatus for removing emboli from a vessel comprising a catheter having an occlusion balloon of uniform thickness that facilitates retrograde flow and efficiently removes emboli.

N \Mclboumc\Cases\Patent\55000-55999\P S482AU.I\Specis\P55482 AU I Specification 2007-2-14.doc 14/02107 4 Summary of the Invention According to one aspect of the present invention there is provided an apparatus comprising: a catheter having proximal and distal ends, a lumen extending therethrough and a blood outlet port in communication with the lumen; an occlusion balloon disposed on the distal end of the catheter and extending beyond the distal end of the catheter when in an expanded state to form a tapered entrance to the lumen; and a syringe adapted to be coupled to the blood outlet port.

According to a further aspect of the present invention there is provided an apparatus comprising: a catheter having a proximal and distal ends, a lumen extending therethrough and a blood outlet port in communication with the lumen; an occlusion balloon disposed on the distal end of the catheter and extending beyond the distal end of the catheter when in an expanded state to form a tapered entrance to the lumen; and a venous return catheter having a proximal end with an inlet port and a distal end with an outlet port, and a lumen extending therebetween, the blood outlet port configured to be coupled to the inlet port of the venous return catheter.

According to a still further aspect of the present invention there is provided an apparatus comprising: a catheter having proximal and distal ends, a lumen extending therethrough and a blood outlet port in communication with the lumen; an occlusion balloon disposed on the distal end of the catheter and extending beyond the distal end of the catheter when in an expanded state to form a tapered entrance to the lumen; and N \Iclbourne\Cases\Patnt\550OO-55999\P55482.AU I\Specis\PS5482AU.I Spccifcation 2007-2-14doc 4/02/07 5 a wire having a distal end and a balloon disposed on the distal end, wherein the wire and balloon are sized to pass through the lumen of the catheter.

Brief Description of the Drawings Further features of the invention, its nature and various advantages will be more apparent from the accompanying drawings and the following detailed description of the preferred embodiments, in which: Figures 1A-1B are, respectively, side and sectional views of a previously known occlusion balloon in contracted and deployed states; Figures 2A-2B are, respectively, a schematic view of apparatus in accordance with the present invention and a cross-sectional view along line A--A of Figure 2A; Figures 3A-3B are side sectional views illustrating a preferred configuration of the distal end of the catheter of Figure 2; Figures 4A-4B are side sectional views of the occlusion balloon of the present invention in contracted and deployed states, respectively; and Figure 5 is a schematic view of apparatus of the present invention being used during an interventional procedure.

Description of the Preferred Embodiments Referring to Figures 1A-1B, a bell-shaped occlusion balloon, as described in applicant's commonly assigned allowed U. S. patent application Serial No. 09/418,727, filed May 8, 2001, which is incorporated herein by reference, is described. Occlusion balloon 20 is shown in contracted and deployed states in Figures 1A and 1B, respectively. Balloon 20 is affixed to distal end 26 of N \Melboume\Cascs\atent\S5OO-S55999\P55482 AU I\Specis\PSS4SZAU I Specification 2007-2-14.doc 4/02107 6 catheter 22, for example, by gluing or a melt-bond, so that opening 27 in balloon 20 leads into lumen 28 of catheter 22. Balloon 20 preferably is wrapped and heat treated during manufacture so that distal portion 29 of the balloon extends beyond the distal end of catheter 22 and provides an atraumatic tip or bumper for the catheter.

In accordance with manufacturing techniques which are known in the art, occlusion balloon 20 comprises a compliant material, such as polyurethane, latex or io polyisoprene which has variable thickness along its length to provide a bell-shape when inflated.

As described hereinabove, the variable thickness characteristic of occlusion balloon 20, which is used to deploy the balloon to the preferred bell-shape, presents certain manufacturing challenges. In particular, manufacturing a balloon having a variable wall thickness can lead to reduced yield due to variability of the manufacturing process. Additionally, a variable thickness balloon may be difficult to manufacture and may have a higher cost relative to a balloon having a uniform thickness.

Referring now to Figures 2, a first embodiment of apparatus constructed in accordance with principles of the present invention is described. Apparatus 40 comprises catheter 41 having proximal and distal ends and working lumen 58 extending therethrough. Catheter 41 comprises occlusion balloon 42 having proximal and distal ends affixed to the distal end of catheter 41, and preferably comprises radiopaque marker band 65 disposed at the distal end of catheter 41 to facilitate positioning of the distal end of the catheter.

Occlusion balloon 42 comprises a uniform thickness material having a contracted state suitable for insertion into a vessel and a deployed state in which occlusion N \Meiboume\Cases\Patcnt\55000-55999\P55482AUAI\Specis\P55482.AU I Spccficaion 2007-2-14.doc 14/0207 7 balloon 42 occludes antegrade flow in the vessel. In the deployed state, occlusion balloon 42 comprises distal taper 66 that is configured to provide a funnel-shaped transition into working lumen 58 so that blood flows in a non-turbulent fashion from a treated vessel into catheter 41. Additionally, distal edge 68 is configured to be in Sclose proximity with an inner wall of a vessel to ND facilitate blood flow into catheter 41 and efficiently remove emboli.

SCatheter 41 preferably comprises inner layer 60 of lowfriction polymeric material, such as polytetrafluoroethylene covered with a layer of flat stainless steel wire braid 61 and polymer cover 62 g. polyurethane, polyethylene, or PEBAX), as shown in Figure 2B. Working lumen 58 is defined as a lumen within an interior surface of inner layer 60. Inflation lumen 63 preferably is disposed within polymer cover 62 so that the inflation lumen does not substantially increase the overall profile of catheter 41.

Apparatus 40 preferably further includes proximal hemostatic port 43, e. a Touhy-Borst connector, inflation port 44, and blood outlet port 48. Inflation port 44 is coupled to inflation lumen 63, which in turn is coupled to occlusion balloon 42. Proximal hemostatic port 43 and working lumen 58 of catheter 41 are sized to permit interventional devices, such as angioplasty balloon catheters, atherectomy devices and stent delivery systems to be advanced through the working lumen when a guidewire (not shown) is positioned within the working lumen.

Blood outlet port 48, which is in fluid communication with working lumen 58, may be coupled to an external aspiration device, e. a syringe, to cause blood flow distal of occlusion balloon 42 to flow into working lumen 58.

Alternatively, in a preferred embodiment, blood outlet N\.Melboume\Case\PatentU 5OOO-55999\P55482AU. I \Specis\P55482.AU. I Specification 2007-2-14.doc 1410207 8 port 48 may be coupled to a venous return catheter to form o an arterial-venous shunt suitable for providing retrograde Sflow in a treatment vessel. This aspiration embodiment comprising an arterial-venous shunt is described in detail in applicant's commonly-assigned, above-incorporated U. S.

patent application Serial No. 09/418,727.

(Nc \O Referring now to Figures 3, a preferred configuration of O catheter 41 and a preferred method for affixing occlusion 10 balloon 42 to the distal end of catheter 41 are described.

SIn Figure 3A, the distal end of catheter 41 is shown from a side sectional view as comprising inner layer 60 covered with a layer of flat stainless steel wire braid 61 and polymer cover 62. Radiopaque marker band 65 preferably is disposed at the distal end of catheter 41 between wire braid 61 and polymer cover 62, as shown in Figure 3A. In accordance with principles of the present invention, occlusion balloon 42 comprises a uniform thickness along its length, as illustrated in Figures 3A-3B.

In a preferred method of manufacture, distal end 50 of occlusion balloon 42 is positioned atop polymer cover 62 near the distal end of catheter 41 and just distal of opening 70 of polymer cover 62, as shown in Figure 3A.

Distal end 50 of occlusion balloon 42 then is affixed to polymer cover 62, preferably using a melt-bond or, alternatively, using a biocompatible glue. At this time, proximal end 52 of occlusion balloon 42 extends freely beyond the distal end of catheter 41, as shown in Figure 3A. For purposes of clarifying terminology used herein, although proximal end 52 of occlusion balloon 42 appears situated distal of distal end 50 in Figure 3A, this is because proximal end 52 will subsequently be everted to extend proximal of distal end 50, as described hereinbelow.

N \MelbounmeCases\alcrn\S5000 -55999\P55482AU I\Specis\155482AU I Spcificafion 2007-2-14doc 14/02/07 9 O In a next manufacturing step, distal section 51 of occlusion balloon 42, which is situated just proximal of Sdistal end 50, is melt-bonded to at least one polymeric layer of catheter 41. Specifically, in a preferred embodiment, distal section 51 of occlusion balloon 42 is melt-bonded to distalmost end 85 of inner layer 60 and, c optionally, to distalmost end 87 of polymer cover 62 to ND form fusion joint 67, as shown in Figure 3A. The meltbonding of the plurality of polymeric materials at fusion joint 67 provides substantially seamless transition 72 between occlusion balloon 42 and inner layer Additionally, because fusion joint 67 is formed from a plurality of compliant polymeric materials, fusion joint 67 is capable of achieving a flexible range of motion.

Proximal end 52 of occlusion balloon 42 then is everted so that it extends proximally and radially outward from catheter 41, as shown in Figures 3B and 4A. Proximal end 52 is affixed to polymer cover 62, preferably using a melt-bond or, alternatively, using a biocompatible glue, at a distance between about 10-20 mm proximal of the distal end of catheter 41, as shown in Figure 4A. This creates inflation chamber 74 between polymer cover 62 and an interior surface of balloon 42. Opening 70, which is disposed in a lateral surface of polymer cover 62, is in fluid communication with inflation lumen 63 and inflation chamber 74, as shown in Figure 3B. Proximal end 52 of occlusion balloon 42 may be stretched while it being affixed to polymer cover 62 so that apparatus 40 may achieve a reduced profile in the contracted state.

The fusion of occlusion balloon 42 to catheter 41 at fusion joint 67 and subsequent eversion of the balloon creates substantially seamless transition 72 into working lumen 58, as shown in Figure 3B. In accordance with principles of the present invention, the provision of substantially seamless transition 72 may help reduce flow N \MclIoume\Cascs\PaenI\550D0055999\P55482.AU I\Specis\P55482 AU I Specification 2007.2-14.doc 14102107 10 impedance into working lumen 58 and enhance flow within a treated vessel.

Referring now to Figures 4A-4B, deployment of apparatus within vessel V of a patient is described. In Figure 4A, occlusion balloon 42 is shown in a contracted state suitable for percutaneous and transluminal insertion into a patient's vessel. Occlusion balloon 42 is inflated via inflation port 44, inflation lumen 63 and opening 70, and deploys to a predetermined configuration having proximal taper 64 and distal taper 66, as shown in Figure 4B. The predetermined configuration may be determined, for example, using a pre-moulding process in accordance with manufacturing techniques that are known in the art. In the deployed state, an outer surface of central section which is formed between proximal and distal tapers 64 and 66, is substantially flush with an inner wall of vessel V.

As will be understood by those skilled in the art, the expanded diameter of central section 75 may be sized accordingly for different vessels.

Distal edge 68 is defined as a section of occlusion balloon 42 that is formed between central section 75 and distal taper 66. In the deployed state, distal edge 68 is configured to be in close proximity with an inner wall of vessel V to facilitate blood flow into working lumen 58 and efficiently remove emboli.

Distal taper 66 provides a funnel-shaped flow transition from distal edge 68 into working lumen 58. Additionally, as described hereinabove, fusion joint 67 provides substantially seamless transition 72 from occlusion balloon 42 into working lumen 58 due to the melt-bond between balloon 42 and inner layer 60 of catheter 41.

Referring now to Figure 5, a preferred method for using apparatus 40 of Figure 2A during an interventional N\Mclbourne\Cases\PalenI\55D00.5999\PSS482AU I\Specis\P5482AU. I Spcification 2007.2-14.doc 1410207 11 O procedure, such as balloon angioplasty, is described. In a first step, guidewire 83 is inserted into a patient's Svasculature and a distal end of guidewire 83 is disposed just proximal of stenosis S, which is located in vessel V.

A dilator (not shown) that is disposed within catheter 41 then is inserted over guidewire 83 to advance catheter 41 Sto a desired position proximal of stenosis S. When D catheter 41 is properly positioned, e. g. as determined 0 under fluoroscopy using radiopaque marker band 65, the 10 dilator may be removed. Occlusion balloon 42 then is Sinflated via inflation port 44 of Figure 2A, preferably using a radiopaque contrast solution, to occlude antegrade flow in vessel V. Aspiration is provided through working lumen 58 of catheter 41 to cause retrograde flow to occur in vessel V distal of occlusion balloon 42, as illustrated by the arrows in Figure Aspiration may be provided through working lumen 58 via blood outlet port 48 using an external aspiration device, e. a syringe, or alternatively using a venous return catheter to form an arterial-venous shunt, as described hereinabove.

An interventional instrument, such as conventional angioplasty balloon catheter 80 having balloon 82, may be loaded through hemostatic port 43 and working lumen 58 and positioned within stenosis S, preferably via guidewire 83.

Hemostatic port 43 is closed and the angioplasty balloon is actuated to disrupt stenosis S. As seen in Figure emboli E formed during the interventional procedure are directed into working lumen 58 via the retrograde flow established.

Occlusion balloon 42 provides a substantially uniform funnel-shaped transition from an inner wall of vessel V into working lumen 58 of catheter 41. Distal edge 68, which is configured to be in close proximity with an inner NWlboumc\Caws\Patent\55000-55999PSS4 I\Sp~i'PS5482AU, I Speificafion 2007-2-14 do 14/02/07 12 wall of vessel V, facilitates flow into working lumen 58 and efficiently removes emboli. Additionally, the funnelshaped transition provided by distal taper 66 and substantially seamless transition 72 into the working lumen via fusion joint 67 improves retrograde flow dynamics into working lumen 58.

Advantageously, because the present invention utilises an occlusion balloon having a uniform thickness and relies on io pre-moulding of the occlusion balloon to obtain the desired deployed shape, a variable thickness occlusion balloon is not required. As noted hereinabove, use of an occlusion balloon having a uniform thickness provides several advantages, including enhanced manufacture, reduced cost and increased reliability.

While preferred illustrative embodiments of the invention are described above, it will be apparent to one skilled in the art that various changes and modifications may be made. The appended claims are intended to cover all such changes and modifications that fall within the true spirit and scope of the invention.

In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word "comprise" or variations such as "comprises" or "comprising" is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.

N \Mclboumc\Cacs\Patcn\55OO*55999\P5548 AU. I\Spvmis\P55482 AU I Spmicaion 2007-2-14.doc 4/02107

Claims

1. Apparatus comprising: a catheter having proximal and distal ends, a lumen extending therethrough and a blood outlet port in communication with the lumen; San occlusion balloon disposed on the distal end NO of the catheter and extending beyond the distal end of the O catheter when in an expanded state to form a tapered entrance to the lumen; and Sa syringe adapted to be coupled to the blood outlet port.

2. The apparatus of claim 1 wherein the lumen has an interior polymer cover.

3. The apparatus of claim 2 wherein the distal end of the occlusion balloon is fused to the interior polymer cover.

4. The apparatus of claim 3 wherein the distal end of the occlusion balloon is adhesively bonded to the interior polymer cover.

5. The apparatus of claim 3 wherein the occlusion balloon further comprises a distal section situated just proximal of the distal end, wherein the distal section of the occlusion balloon is fused to a distalmost end of the interior polymer cover.

6. The apparatus of claim 5 wherein an exterior surface of the catheter comprises an exterior polymer cover.

7. The apparatus of claim 5 wherein the proximal end of the occlusion balloon is fused to the exterior polymer cover. N \Melboume\Cascs\Patcnt\S5000-55999\P55482AU. I\Specis\PS5482AU. I Specification 2007.2-14doc 14/02/07 14

8. The apparatus of claim 7 wherein the proximal end of the occlusion balloon is affixed to the exterior polymer cover at a distance between about 10-20 mm proximal of the distal end of the catheter.

9. The apparatus of claim 7 wherein the proximal end of the occlusion balloon is adhesively bonded to the exterior polymer cover.

10. The apparatus of claim 2 further comprising an inflation lumen disposed within the exterior polymer cover that is in fluid communication with the occlusion balloon.

11. The apparatus of claim 2 further comprising a radiopaque marker band disposed at the distal end of the catheter.

12. The apparatus of claim 11 wherein the catheter comprises a wire braid disposed between the interior polymer cover and the exterior polymer cover, the apparatus further comprising a radiopaque marker band disposed between the wire braid and exterior polymer cover.

13. The apparatus of claim 1, further comprising a wire having a distal end and a balloon disposed on the distal end, wherein the wire and balloon are sized to pass through the lumen of the catheter.

14. The apparatus of claim 1, wherein the catheter has an outer diameter sufficient to permit the catheter to be disposed in the cerebral vasculature. The apparatus of claim 1, wherein the catheter further comprises a second lumen.

N \1lbournc\Case\Paten\5O0O-55999PSS482.AU I\Spccis\P55482AU. I Specification 2007-2-I4doc 14/02/07 15

16. The apparatus of claim 13, wherein the catheter further comprises a second lumen through which the wire and balloon may be inserted.

17. The apparatus of claim 1, wherein the occlusion balloon comprises a wall having a substantially uniform thickness along its length.

18. Apparatus comprising: a catheter having a proximal and distal ends, a lumen extending therethrough and a blood outlet port in communication with the lumen; an occlusion balloon disposed on the distal end of the catheter and extending beyond the distal end of the catheter when in an expanded state to form a tapered entrance to the lumen; and a venous return catheter having a proximal end with an inlet port and a distal end with an outlet port, and a lumen extending therebetween, the blood outlet port configured to be coupled to the inlet port of the venous return catheter.

19. The apparatus of claim 18, further comprising a wire having a distal end and a balloon disposed on the distal end, wherein the wire and balloon are sized to pass through the lumen of the catheter.

The apparatus of claim 18, wherein the catheter further comprises a second lumen.

21. The apparatus of claim 19, wherein the catheter further comprises a second lumen through which the wire and balloon may be inserted.

22. The apparatus of claim 18, wherein the occlusion balloon comprises a wall having a substantially uniform thickness along its length. NVAMclbournt\Cases\Patlrn\55000.55999\PS5482 AU I\Spccis\P55482AU. I Specification 2007-2-14doc 14/02/07 16

23. Apparatus comprising: a catheter having proximal and distal ends, a lumen extending therethrough and a blood outlet port in communication with the lumen; an occlusion balloon disposed on the distal end of the catheter and extending beyond the distal end of the catheter when in an expanded state to form a tapered entrance to the lumen; and a wire having a distal end and a balloon disposed on the distal end, wherein the wire and balloon are sized to pass through the lumen of the catheter.

24. The apparatus of claim 23, further comprising a syringe adapted to be coupled to the blood outlet port.

The apparatus of claim 23, further comprising a venous return catheter having a proximal end with an inlet port and a distal end with an outlet port, and a lumen extending therebetween, the blood outlet port configured to be coupled to the inlet port of the venous return catheter.

26. The apparatus of claim 23, wherein the catheter has an outer diameter sufficient to permit the catheter to be disposed in the cerebral vasculature.

27. The apparatus of claim 23, wherein the catheter further comprises a second lumen.

28. The apparatus of claim 27, wherein the wire and balloon may be inserted through the second lumen.

29. The apparatus of claim 23, wherein the occlusion balloon comprises a wall having a substantially uniform thickness along its length. N :WUcboumc\Cascs\Patcnt\5 000-55999\P55482 AU I\Specis\PS5482 AU I Specficaton 2D07-2 -4 doc 14102/07