Catheter apparatus for treatment of heart arrhythmia

• US 20050038333A1
• Filed: 08/12/2004
• Published: 02/17/2005
• Est. Priority Date: 02/05/2002
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Sra, Jasbir S.
• Granted Patent: US 7,311,705 B2
• Time in Patent Office: Days
• US Class Current: 600/374
• 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 2017/00039 Electric or electromagnetic phenomena other than conductivity, e.g. capacity, inductivity, Hall effect
• CPC Class Codes: A61B 2017/00044 Sensing electrocardiography, i.e. ECG
• CPC Class Codes: A61B 2017/003 Steerable
• CPC Class Codes: A61B 2017/00703 correcting for movement of heart, e.g. ECG-triggered
• CPC Class Codes: A61B 2018/00351 Heart
• CPC Class Codes: A61B 2018/00375 Ostium, e.g. ostium of pulmonary vein or artery
• CPC Class Codes: A61B 2018/00839 Bioelectrical parameters, e.g. ECG, EEG
• CPC Class Codes: A61B 2090/376 using X-rays, e.g. fluoroscopy
• CPC Class Codes: A61B 90/30 Devices for illuminating a surgical field, the devices having an interrelation with other surgical devices or with a surgical procedure

Abstract

A catheter apparatus is provided for use in the treatment of heart arrhythmia having a catheter shaft, a mapping and ablation catheter disposed within the shaft, and a control mechanism coupled to both the shaft and catheter. The catheter shaft includes a main body and a coaxial tip section joined to the main body. The tip section can be rotated about a central axis and curved away from the central axis in a controlled manner. The mapping and ablation catheter can be extended outward from the catheter shaft where it is able to take the form of a pre-stressed curve. The control mechanism controls axial rotation of the tip section, the degree of deflection of the tip section and longitudinal movement of the mapping and ablation catheter with respect to the catheter shaft. Preferably, the mapping and ablation catheter forms a pre-stressed loop when it is fully extended from the catheter shaft. In another aspect of this invention, it provides a method for treatment of a heart arrhythmia having the steps of (1) obtaining cardiac image data from a medical imaging system, (2) creating a 3D model from this cardiac image data, (3) registering the 3D model to an interventional system, (4) introducing a catheter apparatus through an incision into an artery, (5) positioning the catheter apparatus within a chamber of the heart, (6) displaying the catheter apparatus over the registered 3D model on the interventional system, (7) navigating the catheter apparatus within the heart guided by the registered 3D model, and (8) having the catheter apparatus ablate heart tissue at select locations.

Claims

1. A catheter apparatus of the type used in the treatment of heart arrhythmia comprising:

a catheter shaft having a main body and a coaxial tip section joined to the main body, the tip section being rotatable about a central axis and deflectable such that the tip section can be selectively curved away from the central axis;

a mapping and ablation catheter slidably disposed within the catheter shaft, the ablation catheter having a pre-stressed curve whereby the ablation catheter curves as the ablation catheter is extended axially from the catheter shaft; and

a control mechanism coupled to both the catheter shaft and the ablation catheter whereby the control mechanism controls, with respect to the central axis, selective rotation and selective deflection of the tip section and controls selective axial movement of the ablation catheter with respect to the catheter shaft.

2. The apparatus of claim 1 wherein:

the tip section has a distal end; and

a plane substantially defined by the ablation catheter when the ablation catheter is fully extended from the catheter shaft is substantially perpendicular to the distal end.

3. The apparatus of claim 2 wherein the ablation catheter forms a loop when the ablation catheter is fully extended from the catheter shaft.

4. The apparatus of claim 3 wherein the loop has a diameter ranging from 10 mm. to 20 mm.

5. The apparatus of claim 4 wherein the control mechanism controls the diameter of the loop.

6. The apparatus of claim 5 wherein:

the control mechanism is a steering handle;

the steering handle has a first actuator mechanically connected with respect to the catheter shaft whereby actuation of the first actuator can independently rotate the tip section about the central axis and deflect the tip section away from the central axis; and

the steering handle has a second actuator mechanically connected with respect to the ablation catheter whereby actuation of the second actuator can independently move the ablation catheter axially within the catheter shaft and control the diameter of the loop formed by the ablation catheter.

7. The apparatus of claim 6 wherein the ablation catheter includes a spline.

8. The apparatus of claim 7 wherein the spline is fabricated from nickel-titanium having shape memory.

9. The apparatus of claim 1 wherein the ablation catheter has an electrode section at a distal end of the ablation catheter, the electrode section having a plurality of electrodes wherein each electrode is operable to ablate a selected area of heart tissue brought into contact with the electrode.

10. The apparatus of claim 9 wherein at least two electrodes are independently operable.

11. The apparatus of claim 9 wherein each pair of electrodes is separated by a non-ablating section.

12. The apparatus of claim 9 wherein each electrode includes a temperature recording site and an electrogram recording site.

13. The apparatus of claim 1 wherein the tip section can deflect 180°

to the right and to the left of the central axis within a plane coplanar with the central axis.

14. The apparatus of claim 1 wherein the heart arrhythmia is atrial fibrillation.

15. A method for treatment of a heart arrhythmia comprising:

obtaining cardiac image data from a medical imaging system;

creating a 3D model from the cardiac image data;

registering the 3D model with an interventional system;

introducing a catheter apparatus into an artery;

positioning the catheter apparatus in a chamber of the heart;

displaying the catheter apparatus over the registered 3D model with the interventional system;

navigating the catheter apparatus within the heart utilizing the registered 3D model; and

using the catheter apparatus to ablate heart tissue at select locations.

16. The method of claim 15 wherein the heart arrhythmia is atrial fibrillation.

17. The method of claim 15 where the medical imaging system is a computer tomography (CT) system.

18. The method of claim 15 further comprising the step of visualizing the 3D model over a computer workstation of the interventional system.

19. The method of claim 18 wherein the heart arrhythmia is atrial fibrillation and wherein the 3D model is of the left atrium and pulmonary veins.

20. The method of claim 19 wherein the 3D model includes anterior, posterior, right anterior oblique and left anterior oblique views of the left atrium.

21. The method of claim 20 further comprising the step of creating endocardial views of the pulmonary veins from the cardiac image data, whereby the orientation and size of the pulmonary veins can be identified.

22. The method of claim 15 wherein the catheter apparatus comprises:

a catheter shaft having a main body and a coaxial tip section joined to the main body, the tip section being rotatable about a central axis and deflectable such that the tip section can be selectively curved away from the central axis;

a mapping and ablation catheter slidably disposed within the catheter shaft, the ablation catheter having an electrode section selectively moveable axially within the catheter shaft, the electrode section having a plurality of electrodes wherein each electrode is operable to ablate a selected area of heart tissue brought into contact with the electrode and having a pre-stressed curve whereby the electrode section forms a loop when fully extended from the catheter shaft; and

a steering handle coupled to both the catheter shaft and the ablation catheter wherein the steering handle controls with respect to the central axis selective rotation and selective deflection of the tip section and controls with respect to the catheter shaft selective axial movement of the ablation catheter.

23. The method of claim 22 wherein the ablation catheter includes a spline.

24. The method of claim 23 wherein the spline is fabricated from nickel-titanium having shape memory.

25. The method of claim 22 wherein the tip section can deflect 180°

to the right and to the left of the central axis within a plane coplanar with the central axis.

26. The method of claim 22 wherein the loop has a selectively variable diameter and the steering handle controls the diameter of the loop.

27. The method of claim 22 further comprising the steps of:

extending the electrode section from the catheter shaft to position the electrodes in contact with a strategic area of the heart to be ablated;

actuating the electrodes to ablate in a desired manner.

28. The method of claim 27 wherein each of the electrodes is independently operable.

29. The method of claim 28 wherein the actuating step includes selectively activating the electrodes on the electrode section.

30. The method of claim 29 wherein each electrode includes a temperature recording site and an electrogram recording site.

31. The method of claim 30 wherein the navigating step utilizes intracardial recordings of electrical activity taken by at least one electrode and displayed on the interventional system.

32. The method of claim 27 wherein the tip section has a distal end and the loop defines a plane substantially perpendicular to the distal end.

33. The method of claim 32 wherein the steering handle includes:

a first actuator mechanically connected with respect to the catheter shaft whereby actuation of the first actuator can independently rotate the tip section about the central axis and deflect the tip section away from the central axis; and

a second actuator mechanically connected with respect to the ablation catheter whereby actuation of the second actuator can independently move the ablation catheter axially within the catheter shaft and control a diameter of the loop formed by the ablation catheter.

34. The method of claim 33 further comprising the steps of:

deflecting the tip section to a desired orientation;

rotating the catheter shaft to position the tip section adjacent to the strategic area;

fully extending the ablation catheter from the catheter shaft; and

adjusting the diameter of the loop.

35. The method of claim 34 wherein the heart arrhythmia is atrial fibrillation, the strategic area is a junction of a pulmonary vein with the left atrium, and the loop has a diameter whereby the ablation catheter can circumferentially isolate the pulmonary vein.