Acute occlusion of the left main coronary artery following impedance rise after high-frequency catheter ablation.

We present a case of catheter ablation of a premature ventricular complex complicated by left main injury. During ablation from the left coronary cusp, a sudden rise in impedance was followed by ST elevation on the ECG. Angioplasty and stenting were performed immediately; however, the stent subsequently developed repeated stenosis.