CATHETER SYSTEM WITH BALLOON-MOUNTED PLAQUE-MODIFYING ELEMENTS

• US 20130150874A1
• Filed: 12/12/2011
• Published: 06/13/2013
• Est. Priority Date: 12/12/2011
• Status: Active Grant

• Current Assignee: Kassab Kughn Endovascular Devices, LLC
• Original Assignee: Kassab Kughn Endovascular Devices, LLC
• Inventors: Kassab, Elias H.
• Granted Patent: US 8,574,248 B2
• Time in Patent Office: Days
• US Class Current: 606/159
• CPC Class Codes: A61B 17/320725 with radially expandable cutting or abrading elements A61B17/32075 takes precedence
• CPC Class Codes: A61B 2017/22061 for spreading elements apart
• CPC Class Codes: A61L 29/00 Materials for catheters, medical tubing, cannulae, or endoscopes or for coating catheters shape or structure of catheters A61M25/00
• CPC Class Codes: A61M 2025/105 having a balloon suitable for drug delivery, e.g. by using holes for delivery, drug coating or membranes
• CPC Class Codes: A61M 2025/1081 having sheaths or the like for covering the balloon but not forming a permanent part of the balloon, e.g. retractable, dissolvable or tearable sheaths
• CPC Class Codes: A61M 2025/1086 having a special balloon surface topography, e.g. pores, protuberances, spikes or grooves
• CPC Class Codes: A61M 2025/109 having balloons for removing solid matters, e.g. by grasping or scraping plaque, thrombus or other matters that obstruct the flow
• CPC Class Codes: A61M 25/104 used for angioplasty

Abstract

A plaque-modifying balloon and method for use in an endovascular procedure includes an elongated balloon that defines a longitudinal axis and is inflatable from a first deflated configuration to a second radially expanded configuration. One or more plaque-modifying elements are mounted on the outside of the inflatable balloon. Optionally, a compressible sheath made of a relatively low durometer, flexible material is mounted on the balloon to cover the elements during transit of the plaque-modifying balloon to and from the treatment site.

Claims

1. A plaque-modifying catheter system comprising:

a catheter having a proximal end, a distal end and an intermediate section therebetween;

an inner lumen between the proximal and distal ends through which a medical device or fluid may pass without interruption or interference through the inner lumen;

an expandable balloon located between the proximal and distal ends of the catheter and circumscribing at least the intermediate section of the catheter, the balloon receiving a pressurizing fluid between the catheter and the balloon which causes the balloon to inflate, the balloon having an outer surface; and

an assembly of plaque-modifying elements mounted on at least a part of the outer surface of the balloon, thereby creating an array of weakened areas in a vessel wall when the balloon is urged into contact with the vessel wall, at least some of the modifying elements having a tip situated atop a plaque-modifying element, the tip having a cross section geometry selected from the group consisting of a polygon, an oval, a circle, a dome, an ellipse, an “

x”

shape, a star shape and a “

y”

shape.

2. The plaque-modifying catheter system of claim 1, further including:

a retractable sheath that at least partially covers the modifying elements as the catheter system is maneuvered through a tortuous vasculature, is retracted to expose at least a part of the plaque-modifying assembly when the assembly is juxtaposed with a site to be treated, and is repositioned to cover the plaque-modifying assembly before the catheter system is withdrawn.

5. The plaque-modifying catheter system of claim 1, wherein:

the assembly of plaque-modifying elements is normally in a radially collapsed configuration and expansible to a radially expanded configuration, wherein the assembly returns to its radially collapsed configuration when the balloon is deflated;

wherein the plaque-modifying elements are adapted to at least partially penetrate hardened stenotic material when expanded by the balloon in a blood vessel lumen; and

wherein said one or more plaque-modifying elements are disposed between the proximal and distal ends of the catheter proximate a distal end region, the balloon being at least partially covered by a sheath that extends over the elements as the balloon is inflated and deflated.

3. A plaque-modifying expansible assembly extending from a balloon of a balloon catheter, comprising:

a plurality of one or more plaque-modifying elements, the elements being normally in a radially collapsed configuration when the balloon is deflated and being movable to a radially expanded configuration when the balloon is inflated, then returning to its radially collapsed configuration when the balloon is deflated;

the elements being adapted to interface with hardened stenotic material when expanded by the balloon in a blood vessel lumen;

wherein the one or more plaque-modifying elements are disposed at least partially between a proximal and a distal end region of the balloon; and

the balloon having end regions mounted over the catheter, the end regions retaining a pressurizing fluid inside the balloon and outside the catheter as the balloon as the balloon is inflated and deflated.

4. A method for dilating a stenosed region in a blood vessel, the method having steps including:

expanding an inflatable balloon that supports an assembly of plaque-modifying elements to radially outwardly displace the elements within the stenosed region, the assembly extending from an outer surface of the balloon;

wherein the elements are disposed between the balloon and the stenosed region, expanding the balloon causing the elements to influence at least a part of the stenotic material to impart a modified pattern in the stenotic material about an inner wall of the blood vessel as the balloon is in an expanded state; and

radially contracting the balloon, wherein the assembly lies in folds of the balloon as the balloon is being expanded and contracted.

6. A method for dilating a stenosed region in a blood vessel, said method comprising:

expanding an assembly of plaque-modifying elements to radially displace the elements outwardly within a stenosed region of the blood vessel;

wherein the elements are disposed between an expansible balloon and the stenosed region and expanding the balloon causes the elements to modify the stenotic material to leave an impression in the stenotic material about the inner wall of the blood vessel as the balloon is in an expanded state; and

radially contracting the balloon, wherein the elements extend from the balloon as the balloon is expanded and contracted.

21. The method of claim 6, wherein the expanding step is completed in about 1-5 seconds.

22. The method of claim 6, wherein the contracting step is completed in about 1-5 seconds.

23. The method of claim 6, wherein the step of expanding the balloon to modify the stenotic material is completed over a dwell time of about 1-5 minutes.

7. A plaque-modifying catheter system for modifying tissue at a treatment site in a body vessel of a patient, the plaque-modifying balloon comprising:

an elongated balloon defining a longitudinal axis, said balloon being inflatable from a first deflated configuration to a second radially expanded configuration;

an assembly of plaque-modifying elements mounted on said balloon, said elements extending radially from said balloon when said balloon is in an inflated configuration; and

a sheath that covers said elements during transit to and from the treatment site and for withdrawal from between the tissue and the elements to expose the elements for tissue modification upon inflation of the balloon.

8. The plaque-modifying balloon as recited in claim 7 further comprising mounting pads for attaching the elements to the balloon.

9. The plaque-modifying balloon as recited in claim 7 wherein a tip of each element extends a radial distance (X) from said balloon and said balloon inflates by a radial distance (x) where X>

x.

10. The plaque-modifying balloon as recited in claim 7 wherein at least some of the elements has a cross section that is a geometry selected from the group consisting of a polygon, an oval, a circle, a dome, an ellipse, an “

x”

shape, a star shape and a “

y”

shape.

11. The plaque-modifying balloon as recited in claim 9 wherein the distance (X) that characterizes elements closer to the distal end is less than the distance (X) that characterizes elements closer to the proximal end of the balloon to facilitate insertion of the catheter system into the vasculature.

12. The plaque-modifying balloon as recited in claim 9 wherein the balloon covers approximately a distal third of the length of the catheter.

13. The plaque-modifying balloon as recited in claim 7 further including means for delivering maintaining and removing a pressurizing fluid to a chamber located between an inside surface of the balloon and an outside surface of the catheter.

14. The plaque-modifying balloon as recited in claim 7 further including a radio-opaque tip located at the distal end of the balloon.

15. The plaque-modifying balloon as recited in claim 7 wherein the balloon includes polyethylene terephthalate (PET).

16. The plaque-modifying balloon as recited in claim 7 wherein at least some of the plaque-modifying elements include a hard plastic such as polytetrafluoroethylene (PTFE).

17. The plaque-modifying balloon as recited in claim 7 further including a pressurizing fluid selected from the group consisting of a saline solution mixed with an x-ray contrast material or gas selected from the group consisting of nitrous oxide, CO₂, and mixtures thereof.

18. The plaque-modifying balloon as recited in claim 7 wherein the plaque-modifying elements are aligned in longitudinally oriented rows on an outside surface of the balloon.

19. The plaque-modifying balloon as recited in claim 7 wherein the plaque-modifying elements are aligned in laterally oriented rows on an outside surface of the balloon.

20. The plaque-modifying balloon as recited in claim 19 wherein the plaque-modifying elements are staggered so that an element in a row lies longitudinally between adjacent elements in a neighboring lateral row.