ST-segment elevation induced during the transseptal procedure for radiofrequency catheter ablation of atrial fibrillation.

We report two cases of transient coronary artery ischemia manifested as chest discomfort with ST-segment elevation in inferior leads during the transseptal procedure for radiofrequency catheter ablation of atrial fibrillation. This unexpected complication was resolved by intravenous administration of nitrates. All patients exhibited normal coronary arteries in angiography. A neurally mediated pathway activated by the mechanical effects of the transseptal puncture on the interatrial vagal network leading to coronary artery spasm may be considered as a possible explanation of this phenomenon. Coronary artery embolism following the transseptal procedure represents a different underlying mechanism.