A 13-year-old girl, who had undergone interrupted aortic arch repair with an 8-mm graft as a neonate and Fontan completion in childhood, developed ventricular fibrillation due to long-QT syndrome. Cardioverter defibrillator implantation was planned. Preoperative catheterization showed a 45-mmHg aortic pressure gradient and ventricular end-diastolic pressure of 11 mmHg. This indicated that recurrent coarctation had adversely affected ventricular function. After consideration of the patient's age, symptoms and anatomical/surgical complexities, axillo-iliac bypass with cardioverter defibrillator implantation was performed. Postoperative ventricular end-diastolic pressure was 6 mmHg. Axillo-iliac bypass is a surgical option for coarctation that can reduce cardiac afterload.