Radiofrequency Energy Induced Ventricular Fibrillation in a Case of Idiopathic Premature Ventricular Contraction Originating from the Left Ventricular Papillary Muscle

A 15-year-old boy without structural heart disease was admitted for the treatment of frequent episodes of premature ventricular contractions (PVCs). Left ventricular mapping revealed that the origin of PVC was at the posterior papillary muscle. Diastolic small potentials were observed during sinus rhythm with a constant interval following QRS beats. This potential eventually coupled with the ventricular myocardium, resulting in the generation of PVC, and thus preceded QRS by 31 msec. Catheter ablation to this site induced non-sustained ventricular tachycardia, followed by transient ventricular fibrillation. Repeated application of radiofrequency energy eliminated PVC accompanied by the split of the diastolic potential.