Dual curve ablation catheter

• US 5,916,214 A
• Filed: 03/28/1997
• Issued: 06/29/1999
• Est. Priority Date: 05/01/1995
• Status: Expired due to Term

• Current Assignee: Medtronic Cardiorhythm
• Original Assignee: Medtronic Cardiorhythm
• Inventors: Nguyen, Frank, Maguire, Mark A., Cosio, Francisco G.
• Primary Examiner(s): Cohen, Lee S.
• Application Number:
  US08/825,425
• Time in Patent Office: 823 Days
• Field of Search: 606/41, 606/45, 606/49, 128/642, 607/122, 600/374
• US Class Current: 606/41
• CPC Class Codes: A61B 18/14 Probes or electrodes therefor
• CPC Class Codes: A61B 2018/00946 slidable
• CPC Class Codes: A61B 2018/00952 rotatable
• CPC Class Codes: A61M 2025/015 Details of the distal fixation of the movable mechanical means
• CPC Class Codes: A61M 2025/0161 wherein the distal tips have two or more deflection regions
• CPC Class Codes: A61M 25/0054 with regions for increasing flexibility
• CPC Class Codes: A61M 25/0141 having flexible regions as a result of using materials with different mechanical properties
• CPC Class Codes: A61M 25/0144 having flexible regions as a result of inner reinforcement means, e.g. struts or rods
• CPC Class Codes: A61M 25/0147 with movable mechanical means, e.g. pull wires

Abstract

A dual curve ablation catheter (2), especially suited for treating atrial flutter, includes a shaft (4) with a deflectable tip (20) at the distal end (6) and a handle (10) at the proximal end (8). The tip includes a highly flexible distal segment (30), a relatively stiff intermediate segment (28) and a flexible proximal segment (26) so that pulling on a manipulator wire (16) attached to the distal segment causes the distal segment to curve and engage, for example, an isthmus of tissue (106) adjacent the tricuspid valve (104) and the inferior vena cava (98) and causes the proximal segment to curve and press against the wall (110) of the inferior vena cava so to stabilize the catheter. Ablation energy can be supplied through the ablation electrodes (48, 68) simultaneously or one at a time to ablate tissue at the isthmus without the need for moving the catheter.

Claims

1. An anatomically-conforming dual curve ablation catheter comprising:

a shaft having proximal and distal ends with a deflectable tip at the distal end;

said tip including a curved distal segment, an intermediate segment and a curved proximal segment spaced apart from the distal segment by the intermediate segment;

at least one ablation-capable electrode positioned along at least the distal segment of the deflectable tip;

a handle at the proximal end of the shaft;

an ablation energy conductor extending along the shaft between each of said at least one ablation-capable electrode and the handle;

the distal, proximal and intermediate segments have first, second and third stiffnesses, said third stiffness being substantially greater than the second stiffness and the second stiffness being at least as stiff as the first stiffness;

a movable tip deflector device mounted to the handle; and

an axially movable manipulator wire coupling the distal end to the tip deflector device so that movement of the tip deflector device causes the manipulator wire to pull on said distal end causing said distal and proximal curved segments to bend to a first chosen shape, to be conformingly engageable with an ablation target site, and to a second chosen shape, respectively, while said intermediate segment is sufficiently stiff so to remain substantially straight.

2. The catheter according to claim 1 wherein the second stiffness is greater than the first stiffness.

3. An atrial flutter ablation catheter comprising:

a shaft having proximal and distal ends with a deflectable tip at the distal end;

said tip including a distal segment, an intermediate segment and a proximal segment spaced apart from the distal segment by the intermediate segment;

ablation-capable, electrically isolated electrodes positioned along at least the distal segment of the deflectable tip, said electrodes including a tip electrode;

a handle at the proximal end of the shaft;

a movable tip deflector device mounted to the handle;

an axially movable manipulator wire coupling the distal end to the tip deflector device so that movement of the tip deflector device causes the manipulator wire to pull on said distal end causing said distal and proximal segments to bend to first and second chosen shapes while said intermediate segment is sufficiently stiff so to remain substantially straight;

conductors extending along the shaft between the ablation-capable electrodes and the handle;

the distal segment with said first chosen shape conformingly engageable with an isthmus of tissue adjacent a tricuspid valve and an inferior vena cava opening into a right atrium; and

the proximal segment with said second chosen shape pressable against a wall of the inferior vena cava so to stabilize the catheter while ablation energy is deliverable to the isthmus of tissue through said ablation-capable electrodes.

4. The catheter according to claim 3 further comprising a temperature sensor associated with at least one of said ablation-capable electrodes.

5. The catheter according to claim 3 further comprising at least one mapping electrode along the distal segment.

6. An atrial flutter ablation catheter comprising:

a shaft having proximal and distal ends with a deflectable tip at the distal end;

said tip including a distal segment, an intermediate segment and a proximal segment spaced apart from the distal segment by the intermediate segment;

the distal, proximal and intermediate segments having first, second and third stiffnesses, said third stiffness being substantially greater than the second stiffness and the second stiffness being at least as stiff as the first stiffness;

a series of ablation-capable, electrically isolated electrodes positioned along at least the distal segment of the deflectable tip, said electrodes including a tip electrode and a series of circumferential electrodes circumscribing the shaft;

a handle at the proximal end of the shaft;

a movable tip deflector device mounted to the handle;

an axially movable manipulator wire coupling the distal end to the tip deflector device so that movement of the tip deflector device causes the manipulator wire to pull on said distal end causing said distal and proximal segments to bend to first and second chosen shapes while said intermediate segment is sufficiently stiff so to remain substantially straight;

ablation energy conductors extending along the shaft between the ablation-capable electrodes and the handle;

at least one mapping electrode along the distal segment electrically coupled to the handle;

the distal segment with said first chosen shape conformingly engageable with an isthmus of tissue adjacent a tricuspid valve and an inferior vena cava opening into a right atrium; and

the proximal segment with said second chosen shape pressable against a wall of the inferior vena cava so to stabilize the catheter while ablation energy is deliverable to the isthmus of tissue through said ablation-capable electrodes.

7. The catheter according to claim 6 further comprising a temperature sensor associated with at least one of said ablation-capable electrodes.

8. An anatomically-conforming dual curve catheter comprising:

a shaft having proximal and distal ends with a deflectable tip at the distal end;

said tip including a bendable distal segment, an intermediate segment and a bendable proximal segment spaced apart from the distal segment by the intermediate segment;

at least one electrode positioned on the deflectable tip;

a handle at the proximal end of the shaft;

an energy conductor extending along the shaft between said at least one electrode and the handle;

the distal, proximal and intermediate segments having first, second and third stiffnesses, said third stiffness being substantially greater than the second stiffness and the second stiffness being at least as stiff as the first stiffness;

a movable tip deflector device mounted to the handle; and

an axially movable manipulator wire coupling the distal end to the tip deflector device so that movement of the tip deflector device causes the manipulator wire to pull on said distal end causing said distal and proximal segments to bend to a first chosen shape, to be conformingly engageable with a target site, and to a second chosen shape, respectively, while said intermediate segment is sufficiently stiff so to remain substantially straight.

9. An anatomically-conforming dual curve catheter comprising:

a shaft having proximal and distal ends with a deflectable tip at the distal end;

said tip including a bendable distal segment, an intermediate segment and a bendable proximal segment spaced apart from the distal segment by the intermediate segment;

means, actuatable from the proximal end of the shaft, for forming first and second curves along said distal and proximal segments so a part of said deflectable tip is generally conformingly engageable with a target site;

at least one electrode positioned along at least one of the intermediate and distal segments of the deflectable tip;

a handle at the proximal end of the shaft;

an energy conductor extending along the shaft between said at least one electrode and the handle;

the distal segment having a first chosen shape, said distal segment conforming with an isthmus of tissue, located adjacent a tricuspid valve and an inferior vena cava opening into a right atrium, as the target site; and

the proximal segment having a second chosen shape, said proximal segment positioned to be pressable against a wall of the inferior vena cava so to stabilize the catheter while ablation energy is delivered to the isthmus of tissue through said at least one electrode.