Apparatus and method for cardiac ablation

Abstract

A system and method for cardiac mapping and ablation include a multi-electrode catheter introduced percutaneously into a subject's heart and deployable adjacent to various endocardial sites. The electrodes are connectable to a mapping unit, an ablation power unit a pacing unit, all of which are under computer control. Intracardiac electrogram signals emanated from a tachycardia site of origin are detectable by the electrodes. Their arrival times are processed to generate various visual maps to provide real-time guidance for steering the catheter to the tachycardia site of origin. In another aspect, the system also include a physical imaging system which is capable of providing different imaged physical views of the catheter and the heart. These physical views are incorporated into the various visual maps to provide a more physical representation. Once the electrodes are on top of the tachycardia site of origin, electrical energy is supplied by the ablation power unit to effect ablation.

It is claimed:  
     
         1 . A cardiac mapping system for locating a tachycardia site of origin in an endocardium of a subject's heart, comprising: 
 catheter means for disposing a cluster of electrodes about the endocardium site-by-site, each electrode capable of detecting intracardiac electrogram signals emanating from the tachycardia site of origin;    means responsive to the intracardiac electrogram signals detected at each electrode for computing an arrival time of the intracardiac electrogram signals thereat;    means for interactively displaying a map derived from said arrival times of intracardiac electrogram signals, said map including the cluster of electrodes and a display of arrival time associated with each electrode, whereby those electrodes being closer to the tachycardia site of origin than others will register earlier arrival times than others, and electrodes that are substantially coincident with the tachycardia site of origin will register an earliest possible arrival time, thereby said map providing guidance for moving said catheter in the direction of those electrodes having earlier arrival times; and    means for storing and displaying a map obtained from a previous site.