Radiofrequency catheter ablation of accessory bypass tracts has become a widely accepted therapy for Wolff-Parkinson-White (WPW) syndrome. The procedure typically has a high success rate with a low incidence of complications. Left ventricular perforation is a rare but serious complication of catheter ablation. Here we describe a patient who developed left ventricular perforation and a dissecting subepicardial hematoma with cardiac tamponade following catheter ablation for WPW syndrome. Immediate hematoma evacuation and direct repair of the fragile myocardium were performed under cardiopulmonary bypass, and the patient survived with no further complications.