Methods for detection of cardiac rhythm disorders using basket style cardiac mapping catheter

1. A method for sensing multiple local electric voltages from endocardial surface of a heart, comprising:

providing a system for sensing multiple local electric voltages from endocardial surface of a heart, comprising:

a first elongate tubular member having a lumen, a proximal end and a distal end;

a basket assembly comprising:

a plurality of flexible splines for guiding a plurality of exposed electrodes, the splines having proximal portions, distal portions and medial portions therein between, wherein the exposed electrodes are substantially flat electrodes and are substantially unidirectionally oriented towards a direction outside of the basket;

a proximal anchor for securably affixing the proximal portions of the splines; said proximal anchor being secured at the distal end of the first elongate tubular member;

a distal tip consisting essentially of means for only securably affixing the distal portions of the splines, said proximal anchor and said distal tip defining a longitudinal axis therein between about which the splines are disposed; and

a second elongate tubular member having a lumen, a proximal end and a distal end, wherein the basket assembly is slidingly compressible within the lumen of the second elongate tubular member;

wherein the splines approach the distal tip at an angle of about 90° or less than about 90° as measured from a line segment between the proximal anchor and the distal tip along the longitudinal axis;

wherein the splines comprise a superelastic material such that the basket assembly exhibits a substantially cylindrical shape when radially compressed within the second elongate tubular member and exhibits a radially expanded non-spherical shape when not radially compressed within the second elongate tubular member;

wherein each of the splines in the radially expanded non-spherical shape contain a proximal recurve in the proximate portion of the spline at a location near to the proximal anchor of the basket assembly, the proximal recurve comprises a proximal excurvate outward bend and a proximal incurvate inward bend between said proximal excurvate outward bend and said proximal anchor, where an apex of the proximal incurvate inward bend is disposed in a direction toward the distal tip and is further disposed inwardly closer toward the distal tip than the proximal excurvate outward bend;

wherein the splines in the radially expanded non-spherical shape contain an distal excurvate outward bend disposed at the distal portion of the spline at a location near to the distal tip of the basket assembly to bend the splines back towards the proximal anchor; and wherein the splines have a distal incurvate inward bend between said distal tip and said distal excurvate outward bends; and

wherein, when the basket assembly is in said radially expanded non-spherical shape, the splines extend beyond the distal tip and apices of the distal excurvate bends are disposed beyond the distal tip;

delivering the system to the heart;

sliding the basket assembly beyond the distal end of the second elongate tubular member, whereby the splines radially expand into the radially expanded non-spherical shape to dispose the basket assembly within an atrium of the heart;

contacting proximal atrial tissue with the exposed electrodes disposed on the proximal spline portions;

detecting multiple local electric voltages with the exposed electrodes contacting the proximal atrial tissue from endocardial surface thereat;

contacting other atrial tissue with the exposed electrodes disposed on the medial spline portions and the distal spline portions; and

detecting multiple local electric voltages with the exposed electrodes disposed on the medial spline portions and the distal spline portions contacting the other atrial tissue from endocardial surface thereat;

wherein the multiple local electric voltages form an electrocardiogram having a P wave, a QRS complex and a T wave.

2. The method of claim 1 , wherein the splines of the basket assembly are flexible and wherein the method further comprises:

matching contours of the atrium with the splines of the basket assembly.

3. The method of claim 2 , further comprising:

contacting substantially all of the exposed electrodes with the proximal atrial tissue and the other atrial tissue.

4. The method of claim 2 , further comprising:

spatially fixing substantially all of the exposed electrodes with respect to the proximal atrial tissue and the other atrial tissue.

5. The method of claim 1 , further comprising:

minimizing exposure of the exposed electrodes to ventricular signals whereby a substantial portion of atrial signals detected by the system have larger amplitudes than ventricular signals detected by the system.

6. The method of claim 1 , wherein the splines of the basket assembly are flexible and wherein the method further comprises:

matching contours of an atrium with the splines of the basket assembly.

7. The method of claim 6 , further comprising:

contacting substantially all of the exposed electrodes with the proximal atrial tissue and the other atrial tissue.

8. The method of claim 6 , further comprising:

spatially fixing substantially all of the exposed electrodes with respect to the proximal atrial tissue and the other atrial tissue.

9. The method of claim 1 , further comprising:

minimizing exposure of the exposed electrodes to ventricular signals whereby a substantial portion of atrial signals detected by the system have larger amplitudes than ventricular signals detected by the system.

10. The method of claim 1 , wherein the exposed electrodes are selected from the group consisting of copper electrodes, gold electrodes, platinum electrodes, platinum black electrodes, platinum-iridium electrodes and combinations thereof.

11. A method for sensing multiple local electric voltages from endocardial surface of a heart, comprising:

providing a system for sensing multiple local electric voltages from endocardial surface of a heart, comprising:

a first elongate tubular member having a lumen, a proximal end and a distal end;

a basket assembly comprising:

a plurality of flexible splines for guiding a plurality of exposed electrodes, the splines having proximal portions, distal portions and medial portions therein between, wherein the exposed electrodes are substantially flat electrodes and are substantially unidirectionally oriented towards a direction outside of the basket;

a proximal anchor for securably affixing the proximal portions of the splines; said proximal anchor being secured at the distal end of the first elongate tubular member;

a distal tip consisting essentially of means for only securably affixing the distal portions of the splines, said proximal anchor and said distal tip defining a longitudinal axis therein between about which the splines are disposed;

a second elongate tubular member having a lumen, a proximal end and a distal end, wherein the basket assembly is slidingly compressible within the lumen of the second elongate tubular member;

wherein the splines approach the distal tip at an angle of about 90° or less than about 90° as measured from a line segment between the proximal anchor and the distal tip along the longitudinal axis;

wherein the splines comprise a superelastic material such that the basket assembly exhibits a substantially cylindrical shape when radially compressed within the second elongate tubular member and exhibits a radially expanded non-spherical shape when not radially compressed within the second elongate tubular member;

wherein each of the splines in the radially expanded non-spherical shape contain a proximal recurve in the proximate portion of the spline at a location near to the proximal anchor of the basket assembly, the proximal recurve comprises a proximal excurvate outward bend and a proximal incurvate inward bend between said proximal excurvate outward bend and said proximal anchor, where an apex of the proximal incurvate inward bend is disposed in a direction toward the distal tip and is further disposed inwardly closer toward the distal tip than the proximal excurvate outward bend;

wherein the splines in the radially expanded non-spherical shape contain an distal excurvate outward bend disposed at the distal portion of the spline at a location near to the distal tip of the basket assembly to bend the splines back towards the proximal anchor; and wherein the splines have a distal incurvate inward bend between said distal tip and said distal excurvate outward bends; and

wherein, when the basket assembly is in said radially expanded non-spherical shape, the splines extend beyond the distal tip and apices of the distal excurvate bends are disposed beyond the distal tip;

delivering the system to the heart;

sliding the basket assembly beyond the distal end of the second elongate tubular member, whereby the splines radially expand into the radially expanded non-spherical shape to dispose the basket assembly within a chamber of the heart;

contacting proximal heart tissue within the chamber of the heart with the substantially all of exposed electrodes disposed on the proximal spline portions;

detecting multiple local electric voltages with the exposed electrodes contacting the proximal heart tissue from endocardial surface thereat;

contacting other heart tissue within the chamber of the heart with substantially all of the exposed electrodes disposed on the medial spline portions and the distal spline portions; and

detecting multiple local electric voltages with the exposed electrodes disposed on the medial spline portions and the distal spline portions contacting the other heart tissue from endocardial surface thereat;

wherein the multiple local electric voltages form an electrocardiogram having a P wave, a QRS complex and a T wave.

12. The method of claim 11 , further comprising:

spatially fixing substantially all of the exposed electrodes with respect to the proximal heart tissue and the other heart tissue.

13. The method of claim 11 , wherein the exposed electrodes are selected from the group consisting of copper electrodes, gold electrodes, platinum electrodes, platinum black electrodes, platinum-iridium electrodes and combinations thereof.