Effect of Ventricular Pacing on Morbidity in Adults After Fontan Repair.

•Fontan pts who had pacemakers implanted as adults were studied.•Pts with ≥40% ventricular pacing had higher risk of major adverse clinical events.•Increased risk persisted adjusting for NYHA class, Fontan type, and tachyarrhythmia.•This risk should be considered when planning procedures that may cause heart block.