Successful catheter ablation of focal ventricular fibrillation in a patient with nonischemic dilated cardiomyopathy.

A 64-year-old man with nonischemic dilated cardiomyopathy and a biventricular defibrillator presented with recurrent ventricular fibrillation (VF) and defibrillator shocks. Evaluation of the intracardiac electrograms from his defibrillator demonstrated the consistent initiation of VF by unifocal premature ventricular complexes (PVCs). Noncontact mapping demonstrated the origin of the PVC to be near the left ventricular outflow tract toward the mitral valve ring. Several applications of radiofrequency at this position led to complete cessation of PVCs and prevented further VF. He has not had any further ventricular arrhythmias or defibrillator discharges during follow-up.