Unusual perforation of the left ventricle during radiofrequency catheter ablation for ventricular tachycardia.

Cardiac perforation during catheter-based radiofrequency ablation procedures is relatively uncommon but potentially fatal if tamponade ensues. This complication should be promptly recognised. We present a case of incomplete perforation of the left ventricle with transient ST-segment elevation in leads V1 to V3 during catheter ablation of ventricular tachycardia. Complete perforation was avoided because of rapid diagnosis by the detection of subtle changes in electrode potentials and by performing angiography via an externally irrigated ablation catheter lumen.