Balloon catheter tapered shaft having high strength and flexibility and method of making same

• US 9,056,190 B2
• Filed: 02/25/2013
• Issued: 06/16/2015
• Est. Priority Date: 06/30/2006
• Status: Active Grant

• Current Assignee: Abbott Cardiovascular Systems Incorporated (Abbott Laboratories Incorporated)
• Original Assignee: Abbott Cardiovascular Systems Incorporated (Abbott Laboratories Incorporated)
• Inventors: Simpson, John A., Durcan, Jonathan P., Wilson, Bruce M.
• Primary Examiner(s): HUSON, MONICA ANNE
• Application Number:
  US13/775,659
• Publication Number:
  US 20130160932A1
• Time in Patent Office: 841 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: A61L 29/06 obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: A61M 2025/018 Catheters having a lateral opening for guiding elongated means lateral to the catheter
• CPC Class Codes: A61M 2025/0183 Rapid exchange or monorail catheters
• CPC Class Codes: A61M 2025/1031 Surface processing of balloon members, e.g. coating or deposition; Mounting additional parts onto the balloon member's surface
• CPC Class Codes: A61M 25/00 Catheters; Hollow probes dilators A61M29/00; peritoneal catheters A61M1/285; tracheal tubes A61M16/04; for drainage A61M27/00; for uterus, vagina or rectum A61M31/00 ; for measuring or testing A61B; materials for catheters A61L29/00
• CPC Class Codes: A61M 25/0009 Making of catheters or other medical or surgical tubes
• CPC Class Codes: A61M 25/0021 characterised by the form of the tubing A61M25/0054 takes precedence
• CPC Class Codes: A61M 25/0054 with regions for increasing flexibility
• CPC Class Codes: A61M 25/10 Balloon catheters A61M25/0125 takes precedence; embolectomy A61B17/22032; retractors A61B17/02; inflatable balloons for placing stents or stent-grafts A61F2/958 ; stomach balloons for treatment of obesity A61F5/0003; oesophagal tubes A61J15/00
• CPC Class Codes: A61M 25/1006 Balloons formed between concentric tubes
• CPC Class Codes: A61M 25/1029 Production methods of the balloon members, e.g. blow-moulding, extruding, deposition or by wrapping a plurality of layers of balloon material around a mandril
• CPC Class Codes: A61M 25/1034 Joining of shaft and balloon
• CPC Class Codes: A61M 25/1036 Making parts for balloon catheter systems, e.g. shafts or distal ends A61M25/1029 takes precedence
• CPC Class Codes: A61M 25/104 used for angioplasty
• CPC Class Codes: B29C 2049/7831 characterised by pressure values or ranges
• CPC Class Codes: B29C 2049/7879 Stretching, e.g. stretch rod
• CPC Class Codes: B29C 2791/001 Shaping in several steps
• CPC Class Codes: B29C 2949/08 Preforms made of several individual parts, e.g. by welding or gluing parts together
• CPC Class Codes: B29C 48/001 Combinations of extrusion moulding with other shaping operations
• CPC Class Codes: B29C 48/0018 combined with shaping by orienting, stretching or shrinking, e.g. film blowing B29C48/0017 takes precedence
• CPC Class Codes: B29C 48/09 : Articles with cross-sections having partially or fully enclosed cavities, e.g. pipes or channels
• CPC Class Codes: B29C 48/10 : flexible, e.g. blown foils
• CPC Class Codes: B29C 48/11 : comprising two or more partially or fully enclosed cavities, e.g. honeycomb-shaped
• CPC Class Codes: B29C 48/13 : Articles with a cross-section varying in the longitudinal direction, e.g. corrugated pipes
• CPC Class Codes: B29C 49/00 : Blow-moulding, i.e. blowing a preform or parison to a desired shape within a mould; Apparatus therefor
• CPC Class Codes: B29C 49/04 : Extrusion blow-moulding
• CPC Class Codes: B29C 49/08 : Biaxial stretching during blow-moulding
• CPC Class Codes: B29C 49/087 : Means for providing controlled or limited stretch ratio
• CPC Class Codes: B29C 49/18 : using several blowing steps B29C49/16 takes precedence
• CPC Class Codes: B29C 49/64 : Heating or cooling preforms, parisons or blown articles
• CPC Class Codes: B29C 55/26 : biaxial
• CPC Class Codes: B29C 65/02 : by heating, with or without pressure
• CPC Class Codes: B29C 65/48 : using adhesives , i.e. using supplementary joining material; solvent bonding
• CPC Class Codes: B29C 66/1122 : Single lap to lap joints, i.e. overlap joints B29C66/45, B29C66/472, B29C66/52272 take precedence
• CPC Class Codes: B29C 66/24221 : being circular B29C66/51 takes precedence
• CPC Class Codes: B29C 66/53241 : said articles being tubular and said substantially annular single elements being of finite length relative to the infinite length of said tubular articles making T-shaped pieces by joining tubular articles B29C66/52241
• CPC Class Codes: B29C 66/534 : Joining single elements to open ends of tubular or hollow articles or to the ends of bars
• CPC Class Codes: B29C 66/73711 : oriented
• CPC Class Codes: B29C 66/73713 : bi-axially or multi-axially
• CPC Class Codes: B29D 23/001 : Pipes; Pipe joints pleated hoses B29D23/18
• CPC Class Codes: B29K 2105/258 : Tubular
• CPC Class Codes: B29L 2022/022 : Balloons
• CPC Class Codes: B29L 2031/7542 : Catheters

Abstract

Method of making a balloon catheter includes melt-extruding a thermoplastic polymeric material into a tube, cooling the extruded tube, placing the extruded tube within a capture member and biaxially orienting the polymeric material of the extruded tube while simultaneously tapering at least a section of the extruded tube by radially expanding the extruded tube with pressurized media in the tube lumen and axially expanding the extruded tube with an external load applied on at least one end of the tube as an external heat supply traverses longitudinally from a first end to a second end of the extruded tube in the capture member, wherein an overall axial load on the tubing is varied as at least a section of the tube is heated. The method includes cooling the expanded tube to form a tapered biaxially oriented nonporous thermoplastic polymer tubular member and sealingly securing a balloon proximate a distal end of the tubular member.

Claims

1. A method of making a balloon catheter comprising:

a) melt-extruding a thermoplastic polymeric material having a Shore durometer hardness of less than about 75 D at an elevated temperature into a tube having a first outer diameter, a first inner diameter, and a tube lumen defined therein, and cooling the extruded tube to a temperature less than the elevated temperature of the melt-extrusion;

b) placing the extruded tube within a capture member and biaxially orienting the polymeric material of the extruded tube while simultaneously tapering at least a section of the extruded tube by radially expanding the extruded tube with pressurized media in the tube lumen and axially expanding the extruded tube with an external load applied on at least one end of the tube as an external heat supply traverses longitudinally from a first end to a second end of the extruded tube in the capture member, wherein an overall axial load on the tube is varied as at least a section of the tube is heated, wherein varying the overall axial load comprises varying at least one of (i) the external load applied to the end of the tube or (ii) the pressure of the pressurized media in the tube lumen, as the external heat supply traverses along the tube;

c) cooling the expanded tube to room temperature to form a tapered biaxially oriented nonporous thermoplastic polymer tubular member with an inflation lumen defined therein; and

d) sealingly securing a balloon proximate a distal end of the tubular member with an interior of the balloon in fluid communication with the inflation lumen.

2. The method of claim 1 wherein the capture member tapers from a smaller to a larger inner diameter along at least a section of the capture member, and the overall axial load is decreased as the heating nozzle traverses along the tapered section of the capture member from the smaller to the larger inner diameter.

3. The method of claim 1 wherein the overall axial load decreases by an amount such that the tapered section of the tubular member has a tapering outer diameter and wall thickness and a constant inner diameter.

4. The method of claim 1 wherein the overall axial load decreases by an amount such that the tapered section of the tubular member has a tapering outer and inner diameter and a constant wall thickness.

5. The method of claim 1 wherein the capture member has a uniform inner diameter, and the overall axial load is constant as the section is heated.

6. The method of claim 1 including heat stabilizing the expanded tube after b) by heating the tube to a heat stabilizing temperature sufficient to stabilize the polymeric material of the tube.

7. The method of claim 6, wherein the expanded tube is heat stabilized by placing the tube on a mandrel with an outer surface having a shape corresponding to the inner surface shape of the tube.

8. The method of claim 6, wherein the polymeric material is a polyether block amide, and the heat stabilization comprises heating the expanded tube at about 100 to about 140°

C., for about 10 to about 15 minutes.

9. The method of claim 1 wherein the thermoplastic polymeric material has a Shore durometer hardness of between about 55 D and about 75 D.

10. The method of claim 1 wherein the tapered section of the extruded tube comprises at least about 30% of the length of the tubular member.

11. The method of claim 1 wherein the capture member comprises a metallic tube having a lubricious polymeric inner liner, and the pressurized media is a gas at an elevated pressure sufficient to radially expand the extruded tube into contact with an inner surface of the capture member without increasing an outer diameter of the capture member.

12. The method of claim 1 wherein the extruded tube is cooled to room temperature after extrusion and before the radial and axial expansion of the extruded tube.

13. The method of claim 1 wherein the tube is extruded to the first outer diameter of about 0.021 to about 0.023 inches, and the first inner diameter of about 0.004 to about 0.006 inches.

14. The method of claim 1, wherein the thermoplastic polymeric material has a Shore durometer hardness of about 63 D.

15. The method of claim 1, wherein the extruded tube has a maximum blow-up-ratio and the extruded tube is radially expanded to at least 80% of the maximum blow-up-ratio.

16. The method of claim 1, wherein the extruded tube is radially expanded such that the expanded tube has a second inner diameter which is at least about 5 times greater than the first inner diameter of the extruded tube.

17. The method of claim 1, wherein the extruded tube is simultaneously radially and axially expanded.

18. A method of making a balloon catheter comprising:

a) extruding a thermoplastic polymeric material having a Shore durometer hardness of less than about 75 D into a tube having a lumen defined therein;

b) placing the extruded tube in a capture member having an inner diameter which is uniform along a first section extending from a first end of the capture member and which tapers along a second section from a second end of the capture member to the uniform diameter first section, and biaxially expanding the extruded tube to thereby biaxially orient the polymeric material of the extruded tube and taper the wall thickness of the extruded tube, the biaxial expansion comprising;

i) longitudinally traversing a heating nozzle along the length of the capture member to heat the extruded tube therein;

ii) pressurizing the interior of the extruded tube to radially expand the extruded tube; and

iii) applying an external load on at least one end of the extruded tube to axially expand the extruded tube, wherein the external load is substantially constant as the heating nozzle traverses the uniform diameter first section of the capture member and decreases as the heating nozzle traverses along the increasing inner diameter of the second section of the capture member, to form a tapered biaxially oriented tubular member having a first section with a substantially constant outer and inner diameter and wall thickness, and a second section with a substantially constant inner diameter and a tapering outer diameter and wall thickness;

c) heat stabilizing the expanded tube by heating the tube to a heat stabilizing temperature sufficient to stabilize the polymeric material of the tube, wherein the tube is allowed to radially and axial shrink during the heat stabilization;

d) cooling the expanded tube to room temperature to form a biaxially oriented nonporous thermoplastic polymer tubular member with a tapered proximal section and an inflation lumen defined therein; and

e) sealingly securing a proximal skirt section of the balloon to a distal end of the tubular member with an interior of the balloon in fluid communication with the inflation lumen.

19. The method of claim 18, wherein the expanded tube is heat stabilized by placing the tube on a mandrel with an outer surface having a shape corresponding to the inner surface shape of the tube.

20. The method of claim 18 wherein the expanded tube inner diameter radially shrinks by no more than about 10 percent during the heat stabilization.

21. The method of claim 18, wherein the thermoplastic polymeric material has a Shore durometer hardness of between about 55 D and about 75 D.

22. The method of claim 18, wherein the thermoplastic polymeric material has a Shore durometer hardness of about 63 D.

23. The method of claim 18, wherein the extruded tube has a maximum blow-up-ratio and the extruded tube is radially expanded to at least 80% of the maximum blow-up-ratio.

24. A method of making a balloon catheter comprising:

a) melt-extruding a thermoplastic polymeric material having a Shore durometer hardness of less than about 75 D at an elevated temperature into a tube having a first outer diameter, a first inner diameter, and a tube lumen defined therein, and cooling the extruded tube to a temperature less than the elevated temperature of the melt-extrusion;

b) placing the extruded tube within a capture member and biaxially orienting the polymeric material of the extruded tube while simultaneously tapering at least a section of the extruded tube by radially expanding the extruded tube with pressurized media in the tube lumen and axially expanding the extruded tube with an external load applied on at least one end of the tube as an external heat supply traverses longitudinally from a first end to a second end of the extruded tube in the capture member, wherein an overall axial load on the tube is varied as at least a section of the tube is heated;

c) heat stabilizing the expanded tube by heating the tube to a heat stabilizing temperature sufficient to stabilize the polymeric material of the tube;

d) cooling the expanded tube to room temperature to form a tapered biaxially oriented nonporous thermoplastic polymer tubular member with an inflation lumen defined therein; and

e) sealingly securing a balloon proximate a distal end of the tubular member with an interior of the balloon in fluid communication with the inflation lumen.