Adults with repaired tetralogy of Fallot (TOF) face long-term risks of ventricular tachycardia (VT) and sudden cardiac death (SCD). There is no consensus on arrhythmia management during surgical pulmonary valve replacement (PVR). This study assessed whether pre-operative electrophysiological (EP) testing with targeted intraoperative cryoablation of identified anatomical isthmuses during PVR is associated with a reduction in post-operative VT inducibility and long-term risk of clinical VT/SCD.