Macroreentrant ventricular tachycardia mimicking focal ventricular tachycardia in a case with arrhythmogenic right ventricular cardiomyopathy.

A 67-year-old man with ventricular tachycardia (VT) due to arrhythmogenic right ventricular cardiomyopathy (ARVC) underwent electrophysiologic testing. Electroanatomic mapping during the VT seemed to reveal a focal mechanism from near the tricuspid annulus (TA). Several radiofrequency applications delivered at the presumed focus resulted in termination but re-induction of the VT. Additional electroanatomic mapping underneath the TA led to the diagnosis of macroreentrant VT. Several RF applications targeting isolated and late potentials observed there during sinus rhythm eliminated the VT. In ARVC cases, detailed mapping underneath the TA should be performed to reveal the VT mechanism, resulting in suppressing VT recurrences.