Induction of ventricular fibrillation versus monomorphic ventricular tachycardia during programmed stimulation. Role of premature beat conduction delay.

Abstract

The results suggest that 1) initiation of ventricular tachycardia during programmed ventricular stimulation occurs with minimal conduction latency; 2) because of the large overlap in coupling intervals where VF or VT were induced, a single coupling interval cannot be recommended to adequately separate these groups; and 3) induction of VF was preceded by increased latency and prolongation of the local activation time. These parameters should not be allowed to prolong if VF is to be avoided during programmed stimulation. In addition, 4) the initiation of VF during electrophysiological studies is often associated with the presence of structural heart disease; such structural disease may promote conduction latency and the development of VF.