AREAS OF SLOW CONDUCTION IN ATRIAL REENTRANT TACHYCARDIA - A CASE-REPORT AND REVIEW OF THE LITERATURE

An electrophysiologic study of atrial tachycardia is presented. During tachycardia, transient entrainment and sinus rhythm, two patterns of persistent double potentials in the high right atrium and fragmented a ctivity in the low atrial septum were observed. No activity was record ed from multiple areas of the right atrium with endocardial apping dur ing sinus rhythm. The observations suggest that persistent fragmented activity represents slow conduction within the circuit which could be orthodromically entrained. Persistent double potentials probably repre sent slow conduction orthodromically and/or antidromically activated o utside the circuit. However, a wave front from pacing impulses travell ing through this area could entrain the circuit.