Patent ID: 7410486

Claim:
A method for treating atrial arrhythmia by ablating a substantial portion of a circumferential region of tissue in a tubular region of or near the heart of a patient, comprising: providing a circumferential ablation catheter comprising: an elongated tubular catheter body having an outer wall, proximal and distal ends, and at least one lumen extending therethrough; an ablation assembly mounted at the distal end of the catheter body, the ablation assembly comprising: a circumferential ablation element mounted on the distal end of the catheter body; and an inflatable balloon provided in surrounding relation to the circumferential ablation element that is adjustable between a radially collapsed position and a radially expanded position, the inflation balloon contacting a plurality of locations about an inner circumferential region of a generally tubular region of or near the heart; and a stabilization assembly mounted on the catheter distal to the ablation assembly, the stabilization assembly contacting a different plurality of locations about the inner circumferential region of the generally tubular region of or near the heart when the inflatable balloon is in the radially expanded position; wherein the stabilization assembly comprises a tubular structure comprising a generally circular main region that is generally transverse to the catheter body and a generally straight distal region; introducing into a patient the catheter, wherein the circumferential ablation element comprises an ultrasound ablation element coupled to an acoustic energy driver, so that the stabilization assembly is within the tubular region and in contact with the different plurality of locations about the inner circumferential region of the tubular region; contacting the substantial portion of the circumferential region of tissue with at least a portion of the inflatable balloon, such that the ultrasound ablation element is positioned to deliver a substantially circumferential pattern of ultrasound energy through the inflatable balloon to the substantial portion of the circumferential region of tissue; and actuating the acoustic energy driver to ablatively couple the ultrasound ablation element to the substantial portion of the circumferential region of tissue via the inflatable balloon.