Multilayer balloon for bifurcated stent delivery and methods of making and using the same

• US 20080065188A1
• Filed: 09/12/2006
• Published: 03/13/2008
• Est. Priority Date: 09/12/2006
• Status: Active Grant

• Current Assignee: Boston Scientific Scimed, Inc. (Boston Scientific Corporation)
• Original Assignee: Boston Scientific Scimed, Inc. (Boston Scientific Corporation)
• Inventors: Pallazza, Stefan M.
• Granted Patent: US 8,216,267 B2
• Time in Patent Office: Days
• US Class Current: 623/1.11
• CPC Class Codes: A61F 2/856 Single tubular stent with a side portal passage
• CPC Class Codes: A61F 2/954 for placing stents or stent-grafts in a bifurcation
• CPC Class Codes: A61F 2/958 Inflatable balloons for placing stents or stent-grafts
• CPC Class Codes: A61F 2002/821 Ostial stents

Abstract

An expandable medical balloon useful for treatment at a vessel bifurcation, the balloon having at least one expanded state, the balloon having at least one inner layer and at least one outer layer, the outer layer having at least one cavity therein through which the inner layer protrudes when the balloon is in its at least one expanded state, and methods of making and using the same.

Claims

1. An expandable medical balloon useful for treatment of a bifurcated vessel, the balloon comprising at least one continuous inner layer, the inner layer having an inner surface and an outer surface, and at least one outer layer, the outer layer comprising a cavity which extends at least partially through the outer layer.

2. The expandable medical balloon of claim 1 wherein said cavity is an opening which extends through the outer layer exposing the outer surface of the inner layer.

3. The expandable medical balloon of claim 1 having at least one expanded state, the at least one inner layer protruding through the cavity in the at least one outer layer when the balloon is in said at least one expanded state.

4. The expandable medical balloon of claim 1 wherein the at least one outer layer is formed of a material having wherein said outer layer is of a first compliance, and the inner layer is formed of a material wherein said inner layer of a second compliance, the second compliance is less than the first compliance.

5. The expandable medical balloon of claim 1 wherein the at least one outer layer is formed of a material wherein said outer layer is of a first compliance, and the inner layer is formed of a material wherein the inner layer is of a second compliance, the second compliance is greater than the first compliance.

6. The expandable medical balloon of claim 1 wherein the at least one outer layer is formed from at least one material selected from the group consisting of homopolymers, copolymers and terpolymers of ethylene, polyamides, polyalkylene terephthalates, polyimides, polyesters, copolyesters, polycarbonates, polyphenylene sulfides, polypropylene, polyurethanes and mixtures thereof.

7. The expandable medical balloon of claim 1 wherein said inner layer is selected from the group consisting of homopolymers, copolymers and terpolymers of ethylene, polyesters, copolyesters, polyurethanes, polycarbonates, polyamides, polyvinyl chloride, acrylonitrile-butadiene-styrene copolymers, polyether-polyester copolymers, polyether-polyamide copolymers, block copolymers having styrene endblocks and midblocks of isoprene, butadiene, ethylene/propylene, isobutylene and ethylene/butylene, fluoropolymers, polyester-ester elastomers, polyether-ester elastomers, polyether-ether ketone, polyether-block amides and mixtures thereof.

8. The expandable medical balloon of claim 1 having more than one cavity in said at least one outer layer and wherein the inner layer protrudes into each cavity.

9. The expandable medical balloon of claim 1 in combination with a bifurcated stent, the bifurcated stent having a main branch and a side-branch and having an expanded state, and wherein the side-branch of the stent corresponds to the cavity through which the inner layer protrudes, and in the expanded state, the inner layer of the expandable medical balloon protrudes into the side-branch opening of the stent.

10. The expandable medical balloon of claim 8 in combination with a stent delivery catheter.

11. The expandable medical balloon of claim 1 wherein said balloon comprises at least a portion of a stent delivery catheter.

12. A method of making a multilayer expandable balloon for treatment at a vessel bifurcation, the balloon having at least one inner layer and at least one outer layer, the method comprising the steps of:

forming a tubular parison comprising said at least one inner layer of a first polymer material, the inner layer having an inner surface and an outer surface and said at least one outer layer of a second polymer material;

placing said tubular parison in a balloon mold form; and

radially expanding said tubular parison in said balloon mold form to form a multilayer expandable balloon wherein a protrusion of said inner layer is formed in said cavity of said at least one outer layer;

wherein the outer layer has at least one cavity extending at least partially therethrough.

13. The method of claim 12 wherein the cavity in the outer layer is an opening through which the outer layer of the inner layer is exposed.

14. The method of claim 12 wherein said forming step comprises coextruding said at least one inner layer and said at least one outer layer.

15. The method of claim 12 further comprising the step of removing material from said outer layer to form said cavity wherein said removing step comprises laser ablation, chemical etching or grinding.

16. The method of claim 12 wherein said forming step comprises the steps of forming a first tubular parison;

forming a second tubular parison; and

disposing said second tubular parison over said first tubular parison;

wherein the first tubular parison forms said at least one inner layer and said second tubular parison forms said at least one outer layer.

17. The method of claim 12 wherein said forming step comprises intermittent layer coextrusion.

18. The method of claim 12 wherein said first polymer material is different than said second polymer material.

19. The method of claim 12 wherein said at least one outer layer is of a first compliance and said at least one inner layer is of a compliance which is less than that of the outer layer.

20. The method of claim 12 wherein said at least one outer layer is of a first compliance and said at least one inner layer is of a second compliance which is less than that of the outer layer.

21. The method of claim 12 further comprising a stretching step either subsequent to coextrusion of said tubular parison or combined with radial expansion of said tubular parison.

22. The method of claim 12 further comprising heat setting of said expandable medical balloon subsequent to radial expansion.

23. The method of claim 12 further comprising the step of crimping a bifurcated stent onto said balloon, said bifurcated stent having a main branch and a side branch, said side branch corresponding to said cavity of said outer layer.

24. A method of making a multilayer expandable balloon for treatment at a vessel bifurcation, the balloon having at least one inner layer of a first polymer material and at least one outer layer of a second polymer material, the method comprising the steps of:

forming a tubular comprising said at least one inner layer formed of a first polymer material and said at least one outer layer formed of a second polymer material;

radially expanding said tubular parison in said balloon in a first mold form to form a multilayer expandable balloon having at least one inner layer and at least one outer layer;

removing material from said at least one outer layer to form cavity which extends at least partially through the outer layer;

radially expanding said multilayer expandable balloon in a second mold form wherein said a protrusion of said inner layer is formed in said cavity of said at least one outer layer.

25. The method of claim 24 wherein said cavity is an opening extending through the outer layer and exposing the outer surface of the inner layer.