Thinwall guide catheter

• US 5,755,704 A
• Filed: 10/29/1996
• Issued: 05/26/1998
• Est. Priority Date: 10/29/1996
• Status: Expired due to Term

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Lunn, Peter A.
• Primary Examiner(s): Yasko, John D.
• Application Number:
  US08/739,337
• Time in Patent Office: 574 Days
• Field of Search: 604/282, 604/281, 604/280, 604/264, 604/95, 128/656-658
• US Class Current: 604/527
• CPC Class Codes: A61M 2025/0047 the inner layer having a higher lubricity
• CPC Class Codes: A61M 25/0012 with embedded structures, e.g. coils, braids, meshes, strands or radiopaque coils
• CPC Class Codes: A61M 25/005 with embedded materials for reinforcement, e.g. wires, coils, braids
• CPC Class Codes: A61M 25/0053 having a variable stiffness along the longitudinal axis, e.g. by varying the pitch of the coil or braid

Abstract

An apparatus and method of making a thinwall guide catheter useful in delivery of therapeutic devices through a body vessel. The method comprises braiding a flat wire over the surface of a cylindrical core, placing a heat bondable polymer tube over the braid, surrounding the polymer tube with a heat shrink sleeve, heating the assembly to a temperature and for a time period sufficient to expand the core into braid interstices and bond the polymer tube to substantially only the outer surface of the braid and finally removing the heat shrink sleeve and core. The resulting guide catheter has approximately half the wall thickness of prior guide catheters and has excellent column stiffness and kink resistance.

Claims

1. A thinwall guide catheter, comprising:

an elongated braided tube, the braided tube having an outer diameter and an inner diameter, the braided tube having a plurality of elongated wires, one of each of the elongated wires being meshed with an other of each of the elongated wires, one of each of the elongated wires defining with the other of each of the elongated wires a plurality of cross-over points, one of each of the cross-over points having an outer surface, an inner surface, and an intermediate surface, one of each of the cross-over points defining a plurality of interstices, one of each of four adjacent cross-over points defining one of each of the interstices therebetween;

an elongated jacket, the elongated jacket having an inner diameter and an outer diameter, the inner diameter of the elongated jacket being disposed over the outer diameter of the braided tube, the elongated jacket being bonded to one of each of the outer surface of the cross-over points, the elongated jacket being unbonded to one of each of the intermediate surface of the cross-over points, the elongated jacket being unbonded to one of each of the inner surface of the cross-over points;

so that, in response to bending, axial, or torsional loads impressed on the catheter, one of each of the inner and intermediate surfaces of the cross-over points permit one of each of the elongated wires to expand and contract relative to another of each of the elongated wires.

2. The thinwall guide catheter according to claim 1 wherein the braided tube and the elongated jacket have a combined thickness of from about 0.004 to 0.005 inch.

3. The thinwall guide catheter according to claim 1 wherein the elongated wires have a width of from about 0.005 to 0.015 inch and a thickness of from about 0.0007 to 0.0010 inch and the width lies generally parallel to the outer diameter of the braided tube.

4. The thinwall guide catheter according to claim 1 wherein the elongated jacket is formed from a polymer selected from the group consisting of polyether block amides, polyurethanes, polyethylene, polyamides and mixtures thereof.

5. The thinwall guide catheter according to claim 1 wherein the elongated wires are formed from 304 fully tempered stainless steel.

6. The thinwall guide catheter according to claim 1 wherein the braided tube has a predetermined pic count along regions of the catheter when straight, a higher pic count along the inside of regions when bent and a lower pic count along the outside surface of regions when bent.

7. A thinwall guide catheter, comprising:

an elongated braided tube, the braided tube having an outer diameter and an inner diameter, the braided tube having a plurality of elongated wires, one of each of the elongated wires being meshed with an other of each of the elongated wires, one of each of the elongated wires defining with the other of each of the elongated wires a plurality of cross-over points, one of each of the cross-over points having an outer surface, an inner surface, and an intermediate surface, one of each of the cross-over points defining a plurality of interstices, one of each of four adjacent cross-over points defining one of each of the interstices therebetween;

an elongated jacket, the elongated jacket having an inner diameter and an outer diameter, the inner diameter of the elongated jacket being disposed over the outer diameter of the braided tube, the elongated jacket being bonded to one of each of the outer surface of the cross-over points, the elongated jacket being unbonded to one of each of the intermediate surface of the cross-over points, the elongated jacket being unbonded to one of each of the inner surface of the cross-over points, the elongated jacket having a first thickness where the elongated jacket is bonded to one of each of the outer surface of the cross-over points, the elongated jacket having a varying thickness over one of each of the interstices, the elongated jacket having a minimum thickness over the center of one of each of the interstices;

so that, in response to bending, axial, or torsional loads impressed on the catheter, one of each of the inner and intermediate surfaces of the cross-over points permit one of each of the elongated wires to expand and contract relative to another of each of the elongated wires and the elongated jacket is permitted to expand and contract over the interstices.

8. The thinwall guide catheter according to claim 7 wherein the braided tube and the elongated jacket have a combined thickness of from about 0.004 to 0.005 inch.

9. The thinwall guide catheter according to claim 7 wherein the elongated wires have a width of from about 0.005 to 0.015 inch and a thickness of from about 0.0007 to 0.0010 inch and the width lies generally parallel to the outer diameter of the braided tube.

10. The thinwall guide catheter according to claim 7 wherein the elongated jacket is formed from a polymer selected from the group consisting of polyether block amides, polyurethanes, polyethylene, polyamides and mixtures thereof.

11. The thinwall guide catheter according to claim 7 wherein the elongated wires are formed from 304 fully tempered stainless steel.

12. The thinwall guide catheter according to claim 7 wherein the braided tube has a predetermined pic count along regions of the catheter when straight, a higher pic count along the inside of regions when bent and a lower pic count along the outside surface of regions when bent.

13. The thinwall guide catheter according to claim 7 wherein the elongated jacket defines a generally hemispherical shape over one of each of the interstices.

14. A thinwall guide catheter, comprising:

an elongated braided tube, the braided tube having an outer diameter and an inner diameter, the braided tube having a plurality of elongated wires, the braided tube having a predetermined pic count along regions of the catheter when straight, one of each of the elongated wires having a width of from about 0.005 to 0.015 inch and a thickness of from about 0.0007 to 0.0010 inch and the width lies generally parallel to the outer diameter of the braided tube, one of each of the elongated wires being formed from 304 fully tempered stainless steel, one of each of the elongated wires being meshed with an other of each of the elongated wires, one of each of the elongated wires defining with the other of each of the elongated wires a plurality of cross-over points, one of each of the cross-over points having an outer surface, an inner surface, and an intermediate surface, one of each of the cross-over points defining a plurality of interstices, one of each of four adjacent cross-over points defining one of each of the interstices therebetween;

an elongated jacket, the elongated jacket having an inner diameter and an outer diameter, the elongated jacket is formed from a polymer selected from the group consisting of polyether block amides, polyurethanes, polyethylene, polyamides and mixtures thereof, the inner diameter of the elongated jacket being disposed over the outer diameter of the braided tube, the elongated jacket being bonded to one of each of the outer surface of the cross-over points, the elongated jacket being unbonded to one of each of the intermediate surface of the cross-over points, the elongated jacket being unbonded to one of each of the inner surface of the cross-over points, the elongated jacket having a first thickness where the elongated jacket is bonded to one of each of the outer surface of the cross-over points, the elongated jacket having a varying thickness over one of each of the interstices, the elongated jacket having a minimum thickness over the center of one of each of the interstices, the elongated jacket defining a generally hemispherical shape over one of each of the interstices;

so that, the braided tube and the elongated jacket have a combined thickness of from about 0.004 to 0.005 inch, and that, in response to bending, axial, or torsional loads impressed on the catheter, one of each of the inner and intermediate surfaces of the cross-over points permit one of each of the elongated wires to expand and contract relative to another of each of the elongated wires resulting in a higher pic count along the inside of regions when bent and a lower pic count along the outside surface of regions when bent and the elongated jacket is permitted to expand and contract over the interstices.