Abstract
BACKGROUND: Coronary artery aneurysms (CAAs) rarely cause arrhythmias. CASE SUMMARY: A 64-year-old woman presented with palpitations. Electrocardiography revealed frequent monomorphic premature ventricular contractions (PVCs), with a rightward inferior axis and early transition in the precordial leads. Computed tomography identified a giant CAA in the proximal left anterior descending artery, adjacent to the left coronary cusp and the right ventricular outflow tract, with a fistulous connection to the pulmonary artery. Initial endocardial catheter ablation at the right ventricular outflow tract and left coronary cusp was ineffective. Surgical intervention including CAA resection, fistula closure, and epicardial cryoablation resulted in complete elimination of the PVCs. DISCUSSION: Giant CAAs, although rare, may serve as arrhythmogenic substrates for PVCs. Surgical intervention may be required for successful elimination of arrhythmias when catheter ablation fails. TAKE-HOME MESSAGES: This case demonstrates that giant CAAs may serve as arrhythmogenic substrates for PVCs. When catheter ablation fails, surgical management may provide a solution.