Steerable and aimable catheter

• US 4,601,705 A
• Filed: 05/03/1985
• Issued: 07/22/1986
• Est. Priority Date: 10/31/1983
• Status: Expired due to Term

• Current Assignee: Catheter Research Incorporated
• Original Assignee: William C. Mccoy
• Inventors: McCoy, William C.
• Primary Examiner(s): NOT, DEFINED
• Assistant Examiner(s): Smith, Jr., Jerome R.
• Application Number:
  US06/728,634
• Time in Patent Office: 445 Days
• Field of Search: 604/95, 604/264, 604/280, 604/281, 128/6, 128/657
• US Class Current: 604/95.05
• CPC Class Codes: A61B 1/0051 with controlled bending of insertion part
• CPC Class Codes: A61M 25/0158 with magnetic or electrical means, e.g. by using piezo materials, electroactive polymers, magnetic materials or by heating of shape memory materials
• CPC Class Codes: C08L 2201/12 Shape memory
• CPC Class Codes: H01H 37/323 making use of shape memory materials in thermal relays H01H61/0107; release mechanism H01H71/145; treatment of SMF alloys C22F1/006; for control of temperature G05D23/024
• CPC Class Codes: H01H 37/50 with extensible wires under tension

Abstract

A catheter or the like is steerable through cavities within a body and aimable toward organs or tissue within the body. The catheter includes an elongated tubular member having a proximal end and a distal end for insertion into the body, a plurality of temperature-activated memory elements in the distal end of the tubular member, and a core for supporting the memory elements. Each memory element assumes a preset shape when heated to a predetermined temperature. A sleeve is provided to couple slidably each memory element to the core so that each memory element is permitted to slip in relation to the core and also to couple each memory element so that movement of one element results in movement of the other elements. Each memory element is moved to another shape when the memory element coupled thereto is heated to the predetermined temperature. A control system adjacent the proximal end of the tubular member allows an operator to control selectively the temperature of each temperature-activated element to deflect the distal end of the tubular member so as to either direct the course of the tubular member or to direct the distal end of the tubular member toward an organ or tissue within the body.

Claims

1. A catheter comprising

an elongated hollow tubular member having a proximal end and a distal end for insertion into the body,

a core member within the distal end of the hollow tubular member,

at least two temperature-activated memory elements within the distal end of the hollow tubular member, each memory element moving to assume a predetermined shape when heated to a predetermined temperature,

coupling means for coupling one memory element to another memory element so that when the one memory element moves in a first direction to assume its predetermined shape a force is applied to move the other memory element in the first direction and when the other memory element moves in a second direction to assume its predetermined shape a force is applied to move the one memory element in the second direction, the coupling means including sleeve means for slidably coupling each memory element to the core member so that each memory element is permitted to slip in relation to the adjacent core member when at least one of the memory elements moves to assume its predetermined shape, and

control means for selectively heating each memory element to move at least one of the memory elements to assume its predetermined shape to deflect the distal end of the tubular member in a selected direction and to slide each memory element in relation to the adjacent core member so that the memory elements are able to move in slipping relation to the distal end of the core member, whereby maneuverability of the tubular member within the body toward a selected deflected position is increased.

2. The catheter of claim 1, wherein the sleeve means is a resilient tubular jacket for embracing the core member and the memory elements, the tubular jacket having an inner wall defining a slip chamber in which each memory element is able to slip in relation to the core member during selective heating of at least one of the memory elements.

3. The catheter of claim 1, wherein first and second memory elements are coupled to the core member, and the first memory element has a first radius of curvature and the second memory element has a second radius of curvature that is greater than the first radius of curvature when the first memory element moves to assume its predetermined shape.

4. The catheter of claim 1, each memory element includes a tip portion and a body portion and the coupling means further includes wrap means for slidably coupling at least a segment of the body portion of the core member so that the body portion segment is permitted to slip in relation to the core member when at least one of the memory elements moves to assume its predetermined shape.

5. The catheter of claim 1, wherein the core member includes a distal end positioned within the distal end of the hollow tubular member and the sleeve means couples each memory element to the distal end of the core member.

6. The catheter of claim 5, wherein each memory element includes a tip portion and a body portion, and the sleeve means is a tubular jacket including an axially inner sleeve portion for the reception of the distal end of the core member and the tip portions of each memory element and an axially outer sleeve portion for the reception of the distal end of the core member.

7. The catheter of claim 6, wherein the tubular jacket is formed of a resilient material to embrace elastically the received memory elements so that each received memory element both is retainable in a core-guiding position and movable within the resilient tubular jacket to guide the distal end of the core to a selected position.

8. The catheter of claim 7, wherein the core and the tubular member are interconnected so that guided movement of the core in response to operation of at least one memory element moves the tubular member to a selected deflected position.

9. The catheter of claim 5, wherein the distal end of the core member has a forward tip portion, each memory element has a forward tip portion in close proximity to the distal end of the core member, first and second memory elements are positioned on opposite sides of the core member in spaced relation so that the core member is intermediate the first and second memory elements, and movement of the first memory element to assume its predetermined position causes the forward tip portion of the first memory element to move toward the forward tip portion of the core member and the forward tip portion of the second memory element to move away from the forward tip portion of the core member.

10. A catheter comprising

an elongated hollow tubular member having a proximal end and a distal end for insertion into the body,

a core member having a distal end positioned within the distal end of the hollow tubular member and movable therein,

at least two temperature-activated memory elements within the distal end of the hollow tubular member, each memory element having a tip portion and a body portion and moving to assume a predetermined shape when heated to a predetermined temperature,

sleeve means for slidably coupling the tip portion of each memory element to the distal end of the core member so that the tip portion of each memory element is permitted to slip in relation to the adjacent core member when at least one of the memory elements moves to assume its predetermined shape,

wrap means for slidably coupling at least a segment of the body portion to the core member so that the body portion segment is permitted to slip in relation to the adjacent core member when at least one of the memory elements moves to assume its predetermined shape, and

control means for selectively heating each memory element to move at least one of the elements to assume its predetermined shape to deflect the distal end of the tubular member in a selected direction and to slide the tip portion and the body portion segment of each memory element in relation to the adjacent core member so that the memory elements are able to move in slipping relation to the core member, whereby maneuverability of the tubular member within the body toward a selected deflected position is increased.

11. The catheter of claim 10, wherein the wrap means is a continuous filament.

12. The catheter of claim 11, wherein the filament embraces a radially outwardly-facing surface of each of the memory elements in sufficiently tight relation to retain the memory elements in their coupled position while permitting relative slipping movement between each coupled memory element and the core member.

13. The catheter of claim 10, wherein the continuous filament defines a plurality of winding bunches disposed along the length of the core member in spaced-apart relation so that the windings can move along the core member in relation to one another in the spaces therebetween during deflection of the distal end of the tubular member.

14. The catheter of claim 13, wherein each winding bunch includes three filament windings.

15. A catheter comprising

an elongated hollow tubular member having a proximal end and a distal end for insertion into the body,

a core member having a distal end positioned within the distal end of the hollow tubular member and movable therein,

at least two temperature-activated memory elements within the distal end of the hollow tubular member, each memory element assuming a predetermined shape when heated to a predetermined temperature,

sleeve means for slidably coupling each memory element to the distal end of the core member so that each memory element is permitted to slip in relation to the adjacent core member when at least one of the memory elements moves to assume its predetermined shape and for coupling one memory element to another memory element so that when the one memory element moves in a first direction to assume its predetermined shape a force is applied to move the other memory element in the first direction and when the other memory element moves in a second direction to assume its predetermined shape a force is applied to move the one memory element in the second direction, and

control means for selectively heating each memory element so that each memory element slides in relation to the adjacent core member, the one memory element is moved to deflect the distal end of the tubular member in the second direction when the other memory element is heated to assume its predetermined shape, and the other memory element is moved to deflect the distal end of the tubular member in the first direction when the one memory element is heated to assume its predetermined shape, whereby maneuverability of the tubular member within the body toward a selected deflected position is increased.