Torquable catheter and method

• US 5,228,441 A
• Filed: 11/25/1992
• Issued: 07/20/1993
• Est. Priority Date: 02/15/1991
• Status: Expired due to Term

• Current Assignee: BioCardia, Inc
• Original Assignee: Ingemar H. Lundquist
• Inventors: Lundquist, Ingemar H.
• Primary Examiner(s): Cohen, Lee S.
• Assistant Examiner(s): Jastrzab, Jeffrey R.
• Application Number:
  US07/982,237
• Time in Patent Office: 237 Days
• Field of Search: 128/642, 128/784-786, 128/772, 128/774, 128/4, 128/6, 604/95, 604/96, 604/280, 604/282
• US Class Current: 600/380
• CPC Class Codes: A61B 18/14 Probes or electrodes therefor
• CPC Class Codes: A61B 18/1492 having a flexible, catheter-like structure, e.g. for heart ablation A61B18/1477 takes precedence
• CPC Class Codes: A61B 2018/00577 Ablation
• CPC Class Codes: A61B 2018/0091 Handpieces of the surgical instrument or device
• CPC Class Codes: A61B 2018/00916 with means for switching or controlling the main function of the instrument or device
• CPC Class Codes: A61M 25/005 with embedded materials for reinforcement, e.g. wires, coils, braids
• CPC Class Codes: A61M 25/0051 made from fenestrated or weakened tubing layer
• 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
• CPC Class Codes: A61M 25/0136 Handles therefor
• CPC Class Codes: A61M 25/0138 having flexible regions as a result of weakened outer material, e.g. slots, slits, cuts, joints or coils
• CPC Class Codes: A61M 25/0147 with movable mechanical means, e.g. pull wires
• CPC Class Codes: A61N 1/06 for high-frequency therapy

Abstract

Catheter having a high torque capability adapted to be inserted into and through a lumen of a blood vessel comprising a flexible elongate tubular shaft having proximal and distal extremities. The shaft is comprised of a torque tube extending substantially the entire length of the shaft. The torque tube has a cylindrical wall with at least one flexible portion therein with the flexible portion being characterized in that at least one slot is provided in the cylindrical wall subtending an angle of less than 360°. A flexible sleeve encloses the torque tube and serves to cover the flexible portion while permitting the torque tube to bend in the vicinity of the slot a predetermined amount which is less than that which would create a permanent strain in the torque tube.

Claims

1. A catheter for use with a medical device having a high torque capability adapted to be inserted into and through a lumen of a blood vessel comprising a flexible elongate tubular shaft having proximal and distal extremities and a longitudinal axis, said shaft being comprised of a torque tube extending substantially the entire length of the shaft, said torque tube having a cylindrical wall with at least one flexible portion therein, said flexible portion being characterized in that at least one slot is provided in said cylindrical wall subtending an angle of less than 360°

, a flexible sleeve enclosing said torque tube and serving to cover said flexible portion and permitting said torque tube to bend in the vicinity of said slot, a handle adapted to be grasped by the human hand and secured to the proximal extremity of said tubular shaft for causing rotation of the tubular shaft said torque tube being provided with a centrally disposed lumen, a side arm adapter disposed adjacent the handle and having a side arm lumen in communication with the central lumen to permit the medical device to be inserted through the side arm lumen and into the central lumen extending through the torque shaft.

2. A catheter having a high torque capability adapted to be inserted into and through a lumen of a blood vessel comprising a flexible elongate tubular shaft having proximal and distal extremities and a longitudinal axis, said shaft being comprised of a torque tube extending through at least of a portion of the length of the shaft, said torque tube having a cylindrical wall with at least one flexible portion therein, said flexible portion being characterized in that at least one slot is provided in said cylindrical wall subtending an angle of less than 360°

and a flexible sleeve enclosing said torque tube and serving to cover said flexible portion and permitting said torque tube to bend in the vicinity of said slot, said torque tube being segmented into a plurality of separate spaced apart axially aligned parts with slots therebetween and having interconnecting hinges permitting bending at the hinges.

3. A catheter as in claim 2 together with superelastic memory metal elements disposed within the hinges and extending into the segments to cause the segments to return to a position in which the hinges are not bent.

4. A catheter as in claim 3 wherein said superelastic memory elements are formed of TINEL.

5. A catheter as in claim 3 together with first and second pull elements extending longitudinally of the torque tube and being connected to opposite sides of the torque tube adjacent the distal extremity thereof and means connected to the torque tube for operating on the pull elements to cause bending motion of the distal extremity of the catheter.

6. A catheter as in claim 2 wherein said flexible sleeve is formed of a plastic.

7. A catheter as in claim 6 wherein said plastic is a polyolefin.

8. A catheter as in claim 2 wherein said torque tube has a central lumen extending therethrough having a diameter greater than 0.020".

9. A catheter having a high torque capability adapted to be inserted into and through a lumen of a blood vessel comprising a flexible elongate tubular shaft having proximal and distal extremities and a longitudinal axis, said shaft being comprised of a torque tube extending through at least a portion of the length of the shaft, said torque tube having a cylindrical wall with at least one flexible portion therein, said flexible portion being characterized in that at least one slot is provided in said cylindrical wall subtending an angle of less than 360°

and a flexible sleeve enclosing said torque tube and serving to cover said flexible portion and permitting said torque tube to bend in the vicinity of said slot, said torque tube being segmented into a plurality of separate axially aligned segments with slots therebetween and having interconnecting hinges permitting bending at the hinges, said hinges between adjacent segments being spaced 180°

apart with an imaginary axis extending therethrough about which the segments can bend with respect to each other.

10. A catheter as in claim 9 wherein the catheter is provided with a distal extremity and wherein the torque tube at the distal extremity is provided with hinges which lie in a plane longitudinal to the catheter to permit only 2-way bending in a portion of the distal extremity of the catheter.

11. A catheter as in claim 10 wherein the torque tube at another portion of the distal extremity of the catheter is provided with alternate hinges offset by 90°

with respect to each other to permit four-way bending in four directions at said another portion of the catheter.

12. A catheter as in claim 11 together with a coil spring disposed interiorally of the torque tube in the proximal extremity of the catheter.

13. A catheter as in claim 11 wherein the proximal extremity permitting 4-way bending has a length ranging from 2-3 feet and wherein said distal extremity permitting 2-way bending has a length ranging from 2-4 inches.

14. A catheter comprising an elongate flexible body having a longitudinal axis, a proximal end and a distal end, at least a portion of said body having first and second slotted-wall segmants therein, said slotted-wall segments having a plurality of spaced-apart slots spaced longitudinally of the longitudinal axis, certain of said slots in said first segment being radially aligned and certain of the said slots in said second segment being radially aligned but offset readially with respect to the slots as the first segment whereby the first segment can bend in one direction and the second segment can bend in another direction, first means on the proximal end of the body for rotating the body about the longitudinal axis by transmitting twisting torque through the first and second slotted-wall segments and second means on the proximal end of the body for creating bending of the first slotted segment in said one direction and for causing bending of the second slotted segment in said another direction.

15. A catheter according to claim 14 wherein additional of said slots in said first slotted-wall segment are radially aligned but radially offset with respect to said certain slots in the first segemnt whereby the first slotted-wall segment can be bent in two directions in response to operation of the second means.

16. A catheter according to claim 14 wherein additional of said slots in said second slotted-wall segemnt are radially aligned but radially offset with respect to said certain slots in the second segment whereby the second slotted-wall segemnt can be bent in two directions.

17. A catheter as in claim 14 wherein additional of said slots in said second slotted-wall segment are radially aligned in three different portions offset radially to said certain slots whereby the second slotted-wall segment can be bent in four directions.

18. A catheter as in claim 14 wherein said slots subtend at angles of less then 360°

.