Abstract
BACKGROUND: Post-infarction scar-related ventricular tachycardia (VT) originating from the right ventricular (RV) free wall in patients with RV infarction is rare. CASE SUMMARY: A 75-year-old Asian male, with a history of RV infarction after surgery for a giant right coronary artery aneurysm, presented with sustained VT with left bundle branch block and inferior axis morphology. The activation mapping during the VT revealed a focal origin initially propagated from the anterior attachment of the RV wall, and mid-diastolic potentials (MDPs) were detected within the RV free wall close to the anterior attachment. At the MDPs recording site, entrainment pacing showed concealed entrainment. The stimulus-QRS interval was equal to the local electrogram-QRS interval. Successful termination of clinical VT was achieved through radiofrequency delivery targeting the MDPs during the VT. Voltage mapping during sinus rhythm (SR) demonstrated a scar area at the RV free wall. Delayed potentials (DPs) during SR were obtained at the zone of MDPs recorded. Additional ablation was performed to eliminate the DPs, resulting in no further inducibility of VT with programmed stimulation. DISCUSSION: The RV free wall infarction can lead to scar-related arrhythmogenesis. Detailed electrophysiological and functional mapping of such scar areas proved effective in terminating VT.