Successful catheter ablation of epicardial ventricular tachycardia worsened by cardiac resynchronization therapy.

Soon after an upgrade from a single-chamber implantable cardioverter-defibrillator (ICD) to cardiac resynchronization therapy (CRT) with an ICD, a 64-year-old man with non-ischaemic cardiomyopathy began to have increasingly frequent ICD shocks for slow ventricular tachycardia (VT). At electrophysiological study, no clinical VT was induced by endocardial right ventricular pacing, but was easily induced by epicardial left ventricular (LV) pacing via a subxiphoid pericardial approach. The VT was successfully ablated on the LV epicardial surface. This case suggests that epicardial catheter ablation may be an alternative for managing CRT-induced proarrhythmias without the inactivation of LV pacing.