Deflectable catheter

• US 5,865,800 A
• Filed: 10/08/1996
• Issued: 02/02/1999
• Est. Priority Date: 08/19/1993
• Status: Expired due to Fees

• Current Assignee: Boston Scientific Corporation
• Original Assignee: Boston Scientific Corporation
• Inventors: Koblish, Josef V., Kline, Craig R., Hunjan, Kulbir S., Peterson, Thomas H., Mirarchi, Thomas F.
• Primary Examiner(s): Dawson, Glenn K.
• Application Number:
  US08/727,077
• Time in Patent Office: 847 Days
• Field of Search: 604/95, 604/280, 604/264, 604/281, 604/282, 604/164, 606/1, 606/32, 606/34, 606/41, 606/108, 600/433-435, 600/585
• US Class Current: 604/95.04
• CPC Class Codes: A61B 17/221 Gripping devices in the form of loops or baskets for gripping calculi or similar types of obstructions surgical snare instruments A61B17/32056
• CPC Class Codes: A61B 17/2909 Handles
• CPC Class Codes: A61B 17/32056 Surgical snare instruments for removing or smashing calculi A61B2017/2212; tonsillotomes A61B17/26
• CPC Class Codes: A61B 18/24 with a catheter A61B18/26, A61B18/28 take precedence
• CPC Class Codes: A61B 2017/00849 with respect to tissue, e.g. hollow organs
• CPC Class Codes: A61B 2017/00853 low friction, hydrophobic and corrosion-resistant fluorocarbon resin coating (ptf, ptfe, polytetrafluoroethylene)
• CPC Class Codes: A61B 2017/22038 with a guide wire
• CPC Class Codes: A61B 2017/22051 with an inflatable part, e.g. balloon, for positioning, blocking, or immobilisation A61B2017/22048, A61B2017/3486 take precedence
• CPC Class Codes: A61B 2017/2212 having a closed distal end, e.g. a loop
• CPC Class Codes: A61B 2017/2215 having an open distal end
• CPC Class Codes: A61B 2017/2912 transmission of forces to actuating rod or piston
• CPC Class Codes: A61B 2017/292 connection of actuating rod to handle, e.g. ball end in recess
• CPC Class Codes: A61B 2017/301 with three legs
• CPC Class Codes: A61B 2018/1407 Loop
• CPC Class Codes: A61M 2025/015 Details of the distal fixation of the movable mechanical means
• CPC Class Codes: A61M 25/0133 Tip steering devices
• CPC Class Codes: A61M 25/0136 Handles therefor
• CPC Class Codes: A61M 25/0147 with movable mechanical means, e.g. pull wires
• 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

Abstract

For achieving, e.g., an improved electrophysiology catheter for examination of the heart, or a catheter accessing the brain, the invention, in one aspect, features an elongated wound wire coil extending through the hollow catheter body of a steerable catheter. The coil is constructed and arranged to enable the catheter body to withstand reactive compressive load without distortion during application of tension on the pull wire and to transmit torque from the proximal to the distal tip portion of the catheter to enhance fidelity of rotational positioning of the distal tip in response to rotational orientation of the proximal portion of the catheter. The coil is shown in frictional torque-transmitting relationship with the interior of the hollow shaft substantially along the common length of the catheter body when the catheter is bent. Steerable catheters with augmented throw for one-handed operation and important improvements in construction features are also shown.

Claims

1. An axially elongated steerable catheter comprising:

an elongated flexible outer hollow catheter body defining a proximal portion and a longitudinal axis;

a deflectable tip portion deflectable relative to said hollow catheter body;

a pull wire extending through said hollow catheter body to a region on said deflectable tip portion distal of the region about which said deflectable tip portion deflects, said pull wire arranged to apply tension on said deflectable portion to produce tip deflection tip; and

an elongated wound wire coil extending through the hollow catheter body,

said coil constructed and arranged to enable said hollow catheter body to withstand reactive compressive load without distortion during application of tension on said pull wire and to transmit torque along the longitudinal axis from the proximal portion to the deflectable tip portion of said catheter to enhance the fidelity of rotational positioning of the deflectable tip portion in response to change of rotational orientation of the proximal portion of the hollow catheter body, said coil being in torque-transmitting relationship with the interior of said hollow catheter body substantially along the common length of the hollow catheter body and the coil, so that when said catheter is bent within the body such that rotational drag is imposed on said hollow catheter body that tends to cause the deflectable tip portion to lag the proximal portion, said coil applies torque to said hollow catheter body to provide high fidelity transmission of rotational position from the proximal end to said deflectable tip portion of said catheter.

2. The steerable catheter of claim 1 wherein said coil is formed separately from said hollow catheter body, said coil comprises an elongated tightly wound wire, and the ratio of the clearance between the outer surface of the coil and the internal surface of the hollow catheter body and the transverse cross-sectional dimension of said wire in the radial direction of said coil, is less than 0.9.

3. The steerable catheter of claim 2 wherein the tightly wound wire comprises wire with a circular cross-section and said ratio of said clearance to the diameter of said wire is less than 0.6.

4. The catheter of claim 2 wherein said surfaces are exposed and adapted for torque-transmitting contact with each other in regions where the hollow catheter body is bent, the coefficient of friction of the internal surface of said hollow catheter body being at least about 0.3.

5. The catheter of claim 4 wherein the internal surface of said hollow catheter body is a urethane polymer, and the outside surface of said coil is metal.

6. The catheter of claim 1 wherein the proximal end of said coil is fixedly attached to the proximal end of said hollow catheter body.

7. The catheter of claim 1 wherein the distal end of said coil is fixedly attached to the distal end of said hollow catheter body.

8. The catheter of claim 1 wherein said coil has an outside diameter that is at most 0.010 inch less than the internal diameter of said hollow catheter body.

9. The hollow catheter body of claim 1 wherein said catheter is an electrophysiology catheter further comprising at least one electrode mounted on said deflectable tip portion, and an insulated conducting wire fixedly attached to said electrode extends through said hollow catheter body to the proximal end, said conducting wire constructed to deliver electrical signals to and from said electrode for mapping or ablation of myocardium tissue.

10. The catheter of claim 1 wherein said pull wire is generally coaxial with said hollow catheter body.

11. An axially elongated steerable catheter, comprising:

an elongated flexible outer hollow catheter body defining a proximal portion and a longitudinal axis;

a deflectable tip portion deflectable relative to said hollow catheter body;

a pull wire extending through said hollow catheter body to a region on said deflectable tip portion distal of the region about which said deflectable tip portion deflects, said pull wire arranged to apply tension on said deflectable tip portion to produce tip deflection; and

an elongated wound wire coil extending through the hollow catheter body formed separately from said hollow catheter body from an elongated tightly wound wire having a rectangular cross-section,

said coil constructed and arranged to enable said hollow catheter body to withstand reactive compressive load without distortion during application of tension on said pull wire and to transmit torque along the longitudinal axis from the proximal portion to the deflectable tip portion of said catheter to enhance the fidelity of rotational positioning of the deflectable tip portion in response to change of rotational orientation of the proximal portion of the hollow catheter body, said coil being in torque-transmitting relationship with the interior of said hollow catheter body substantially along the common length of the catheter hollow body and the coil so that when said hollow catheter body is bent within the body such that rotational drag is imposed on said hollow catheter body that tends to cause the deflectable tip portion to lag the proximal portion, said coil applies torque to said hollow catheter body to provide high fidelity transmission of rotational position from the proximal end of said hollow catheter body to said deflectable tip portion of said hollow catheter body;

whereby the ratio of the clearance between the outer surface of the coil and the internal surface of the hollow catheter body and the transverse cross-sectional dimension of said wire in the radial direction of said coil, being less than 0.9.

12. A axially elongated steerable catheter, comprising:

an elongated flexible outer hollow catheter body defining a proximal portion and a longitudinal axis and being formed from a braided metal wire shaft with a polymeric coating;

a deflectable tip portion deflectable relative to said hollow catheter body;

a pull wire extending through said hollow catheter body to a region on said deflectable tip portion distal of the region about which said deflectable tip potion deflects, said pull wire arranged to apply tension on said deflectable portion to produce tip deflection tip; and

an elongated wound wire coil extending through the hollow catheter body;

said coil constructed and arranged to enable said hollow catheter body to withstand reactive compressive load without distortion during application of tension on said pull wire and to transmit torque along the longitudinal axis from the proximal portion to the deflectable tip portion of said catheter to enhance the fidelity of rotational positioning of the deflectable tip portion in response to change of rotational orientation of the proximal portion of the hollow catheter body, said coil being in torque-transmitting relationship with the interior of said hollow catheter body substantially along the common length of the hollow catheter body and the coil, so that when said hollow catheter body is bent within the body such that rotational drag is imposed on said hollow catheter body that tends to cause the deflectable tip portion to lag the proximal portion, said coil applies torque to said hollow catheter body to provide high fidelity transmission of rotational position from the proximal end to said deflectable tip portion of said hollow catheter body.

13. An axially elongated steerable catheter, comprising:

an elongated flexible outer hollow catheter body defining a proximal portion and a longitudinal axis;

a deflectable tip portion deflectable relative to said hollow catheter body;

a pull wire extending through said hollow catheter body to a region on said deflectable tip portion distal of the region about which said deflectable tip potion deflects, said pull wire arranged to apply tension on said deflectable tip portion to produce tip deflection; and

an elongated wound wire coil extending through the hollow catheter body, at least a distal portion of said coil including a flattened region constructed and arranged to facilitate bending of said coil in the direction of deflection of said deflectable tip portion when tension is applied to said pull wire,

said coil constructed and arranged to enable said hollow catheter body to withstand reactive compressive load without distortion during application of tension on said pull wire and to transmit torque along the longitudinal axis from the proximal portion to the deflectable tip portion of said catheter to enhance the fidelity of rotational positioning of the deflectable tip portion in response to change of rotational orientation of the proximal portion of the hollow catheter body, said coil being in torque-transmitting relationship with the interior of said hollow catheter body substantially along the common length of the catheter body and the coil, so that when said hollow catheter body is bent within the body such that rotational drag is imposed on said hollow catheter body that tends to cause the deflectable tip portion to lag the proximal portion, said coil applies torque to said hollow body to provide high fidelity transmission of rotational position from the proximal end to said deflectable portion of said hollow catheter body.

14. An axially elongated steerable catheter, comprising:

an elongated flexible outer hollow catheter body defining a proximal portion and a longitudinal axis;

a deflectable tip portion deflectable relative to said hollow catheter body;

a pull wire extending through said hollow catheter body to a region on said deflectable tip portion distal of the region about which said deflectable tip potion deflects, said pull wire arranged to apply tension on said deflectable tip portion to produce tip deflection;

an elongated wound wire coil extending through the hollow catheter body,

said coil constructed and arranged to enable said hollow catheter body to withstand reactive compressive load without distortion during application of tension on said pull wire and to transmit torque along the longitudinal axis from the proximal portion to the deflectable tip portion of said catheter to enhance the fidelity of rotational positioning of the deflectable tip portion in response to chance of rotational orientation of the proximal portion of the hollow catheter body, said coil being in torque-transmitting relationship with the interior of said hollow body substantially along the common length of the hollow catheter body and the coil, so that when said hollow catheter body is bent within the body such that rotational drag is imposed on said hollow catheter body that tends to cause the deflectable tip portion to lag the proximal portion, said coil applies torque to said hollow catheter body to provide high fidelity transmission of rotational position from the proximal end to said deflectable tip portion of said hollow catheter body; and

a control handle at the proximal end of the hollow catheter body including

a housing having a piston chamber therein, and

a piston having proximal and distal ends and a longitudinal bore therethrough, said piston being slidably mounted in the piston chamber, said distal end of said piston being fixedly coupled to the proximal end of said hollow catheter body,

the proximal end of said pull wire being attached to said housing at a location proximal to the piston chamber, said pull wire extending through the bore on the piston, the interior of the hollow catheter body and into the distal lumen of the deflectable tip portion, whereby longitudinal movement of the piston relative to the housing results in deflection of the deflectable tip portion.

15. An axially elongated steerable catheter, comprising:

an elongated flexible outer hollow catheter body defining a proximal portion and a longitudinal axis;

a deflectable tip portion deflectable relative to said hollow catheter body;

a pull wire extending through said hollow catheter body to a region on said deflectable tip portion distal of the region about which said deflectable tip potion deflects, said pull wire arranged to apply tension on said deflectable tip portion to produce tip deflection;

an elongated wound wire coil extending through the hollow catheter body,

said coil constructed and arranged to enable said hollow catheter body to withstand reactive compressive load without distortion during application of tension on said pull wire and to transmit torque along the longitudinal axis from the proximal portion to the deflectable tip portion of said catheter to enhance the fidelity of rotational positioning of the deflectable tip portion in response to change of rotational orientation of the proximal portion of the hollow catheter body, said coil being in torque-transmitting relationship with the interior of said hollow body substantially along the common length of the hollow catheter body and the coil, so that when said hollow catheter body is bent within the body such that rotational drag is imposed on said hollow catheter body that tends to cause the deflectable tip portion to lag the proximal portion, said coil applies torque to said hollow catheter body to provide high fidelity transmission of rotational position from the proximal end to said deflectable tip portion of said hollow catheter body; and

a handle attached to the proximal portion of said hollow catheter body, and constructed for one-handed operation, said handle having a movable member attached to the proximal portion of said pull wire, said hollow handle being characterized in that movement of said member a given distance relative to said catheter body, causes said pull wire to move a substantially greater distance than said given distance, to enhance the range of tip deflection.

16. The catheter of claim 15 wherein said movable member includes a pulley surface bodily movable therewith, said pull wire being trained about said pulley surface.

17. The catheter of claim 16 wherein said pulley surface is defined by a rigid formation rigidly joined to said movable member, about which relative sliding motion of said pull wire occurs during actuation.

18. An axially elongated steerable catheter, comprising:

an elongated flexible outer hollow catheter body defining a proximal portion and a longitudinal axis,

a deflectable tip portion deflectable relative to said hollow catheter body, the proximal end of said deflectable tip portion being bonded to the distal end of said hollow catheter body;

said proximal end of said deflectable tip portion being constructed from a material more flexible than said hollow catheter body;

a pull wire extending through said hollow catheter body to a region on said deflectable tip portion distal of the region about which said deflectable tip portion deflects, said pull wire arranged to apply tension on said deflectable tip portion to produce tip deflection;

an elongated wound wire coil extending through the hollow catheter body,

said coil constructed and arranged to enable said hollow catheter body to withstand reactive compressive load without distortion during application of tension on said pull wire and to transmit torque along the longitudinal axis from the proximal portion to the deflectable tip portion of said catheter to enhance the fidelity of rotational positioning of the deflectable tip portion in response to change of rotational orientation of the proximal portion of the hollow catheter body, said coil being in torque-transmitting relationship with the interior of said hollow catheter body substantially along the common length of the hollow catheter body and the coil, so that when said hollow catheter body is bent within the body such that rotational drag is imposed on said hollow catheter body that tends to cause the deflectable tip portion to lag the proximal portion, the coil applies torque to said hollow body to provide high fidelity transmission of rotational position from the proximal end to said deflectable tip portion of said hollow catheter body; and

a safety wire fixedly attached to both said deflectable tip portion and said catheter body for providing flexible attachment therebetween.

19. An axially elongated steerable electrophysiology catheter of the type having a distal tip portion deflectable in a plane in response to a pull wire within the catheter and capable of being torqued at its proximal portion to change the rotational orientation of the tip portion about the longitudinal axis, said catheter comprising:

an elongated flexible outer hollow catheter body;

a deflectable tip portion deflectable relative to said hollow catheter body;

a pull wire extending through said hollow catheter body to a region on said deflectable tip portion distal of the region about which said deflectable tip portion deflects, said pull wire arranged to apply tension on said deflectable portion to produce tip deflection;

a handle attached to the proximal portion of said hollow catheter body, said handle having a movable member attached to the proximal portion of said pull wire, said handle being characterized in that movement of said member a given distance relative to said hollow catheter body causes said pull wire to move a substantially greater distance than said given distance, thereby applying tension on said deflectable portion to produce tip deflection;

at least one electrode mounted on said deflectable tip portion; and

an insulated conducting wire fixedly attached to said electrode extending through said catheter to the proximal end, said conducting wire constructed to deliver electrical signals to and from said electrode for mapping or ablation of myocardium tissue.

20. A catheter, comprising:

a substantially elongate, flexible and hollow catheter body defining a proximal portion, a distal portion and a longitudinal axis;

a deflectable tip portion associated with the distal portion of the catheter body and deflectable relative to the catheter body;

a pull wire extending through the catheter body to a region of the deflectable tip portion, the pull wire being arranged to apply tension to the deflectable tip portion to produce tip portion deflection; and

an elongate wire coil, extending through the catheter body and adapted to transmit torque to the catheter body in response to a change in rotational orientation of the proximal portion of the catheter body when the catheter body is bent;

wherein the catheter body defines an interior surface, the coil defines an exterior surface and the distance between the interior surface of the catheter body and the exterior surface of the coil is at most 0.005 inch when the coil and catheter body are coaxial.

21. A catheter, comprising:

a substantially elongate, flexible and hollow catheter body defining a proximal portion, a distal portion and a longitudinal axis;

a deflectable tip portion associated with the distal portion of the catheter body and deflectable relative to the catheter body;

a pull wire extending through the catheter body to a region of the deflectable tip portion, the pull wire being arranged to apply tension to the deflectable tip portion to produce tip portion deflection; and

an elongate wire coil, extending through the catheter body and adapted to transmit torque to the catheter body in response to a change in rotational orientation of the proximal portion of the catheter body when the catheter body is bent;

wherein the coil comprises a wire having a rectangular cross-section and defines an exterior surface, the catheter body defines an interior surface, and the ratio of clearance between the exterior surface of the coil and the interior surface of the catheter body to the transverse cross-sectional dimension of the wire in the radial direction of said coil, is less than 0.9.

22. A catheter, comprising:

a substantially elongate, flexible and hollow catheter body defining a proximal portion, a distal portion and a longitudinal axis;

a deflectable tip portion associated with the distal portion of the catheter body and deflectable relative to the catheter body;

a pull wire extending through the catheter body to a region of the deflectable tip portion, the pull wire being arranged to apply tension to the deflectable tip portion to produce tip portion deflection; and

an elongate wire coil, extending through the catheter body and adapted to transmit torque to the catheter body in response to a change in rotational orientation of the proximal portion of the catheter body when the catheter body is bent;

wherein the coil comprises a wire having a circular cross-section and defines an exterior surface, the catheter body defines an interior surface, and the ratio of clearance between the exterior surface of the coil and the interior surface of the catheter body to the diameter of the wire, is less than 0.6.

23. A catheter, comprising:

a substantially elongate, flexible and hollow catheter body defining an interior surface, a proximal portion, a distal portion and a longitudinal axis;

a deflectable tip portion associated with the distal portion of the catheter body and deflectable relative to the catheter body;

a pull wire extending through the catheter body to a region of the deflectable tip portion, the pull wire being arranged to apply tension to the deflectable tip portion to produce tip portion deflection; and

a spring coil defining an exterior surface extending through the catheter body, the exterior surface of the spring coil and the interior surface of the catheter body defining a predetermined distance therebetween, the predetermined distance being such that the spring coil will transmit torque to the catheter body in response to a change in rotational orientation of the proximal portion of the catheter body when the catheter body is bent;

wherein the distance between the interior surface of the catheter body and the exterior surface of the coil is at most 0.005 inch when the coil and catheter body are coaxial.

24. A catheter, comprising:

a substantially elongate, flexible and hollow catheter body defining an interior surface, a proximal portion, a distal portion and a longitudinal axis;

a deflectable tip portion associated with the distal portion of the catheter body and deflectable relative to the catheter body;

a pull wire extending through the catheter body to a region of the deflectable tip portion, the pull wire being arranged to apply tension to the deflectable tip portion to produce tip portion deflection; and

a spring coil defining an exterior surface extending through the catheter body, the exterior surface of the spring coil and the interior surface of the catheter body defining a predetermined distance therebetween, the predetermined distance being such that the spring coil will transmit torque to the catheter body in response to a change in rotational orientation of the proximal portion of the catheter body when the catheter body is bent;

wherein the coil comprises a wire having a rectangular cross-section and the ratio of clearance between the exterior surface of the coil and the interior surface of the catheter body to the transverse cross-sectional dimension of the wire in the radial direction of said coil, is less than 0.9.

25. A catheter, comprising:

a substantially elongate, flexible and hollow catheter body defining an interior surface, a proximal portion, a distal portion and a longitudinal axis;

a deflectable tip portion associated with the distal portion of the catheter body and deflectable relative to the catheter body;

a pull wire extending through the catheter body to a region of the deflectable tip portion, the pull wire being arranged to apply tension to the deflectable tip portion to produce tip portion deflection; and

a spring coil defining an exterior surface extending through the catheter body, the exterior surface of the spring coil and the interior surface of the catheter body defining a predetermined distance therebetween, the predetermined distance being such that the spring coil will transmit torque to the catheter body in response to a change in rotational orientation of the proximal portion of the catheter body when the catheter body is bent;

wherein the coil comprises a wire having a circular cross-section and the ratio of clearance between the exterior surface of the coil and the interior surface of the catheter body to the diameter of the wire, is less than 0.6.