In 1970, a 19 year-old man was diagnosed as having coarctation of the aorta (CoA). But the patient and his family rejected further examination for CoA and high blood pressure was treated after that time. When the patient was 37 years old, he was admitted to our hospital because of congestive heart failure. During the 2nd admission for determining the operability of CoA in December, 1988, non-sustained ventricular tachycardia was detected. Immediately, intravenous administration of lidocaine or/and mexiletine were started. However, cardiac arrest occurred. After his recovery, lethal ventricular arrhythmias were still observed frequently despite administration of class Ia or Ib antiarrhythmic drugs. Oral amiodarone administration (600 mg) with procainamide (1000 mg) was started on 1st of May, 1989. Axillo-femoral bypass graft was performed during the 2nd admission because curable operation was abandoned because of severely impaired cardiac function. Subsequently, the patient was admitted 5 times due to exacerbated congestive heart failure. However, lethal arrhythmias were able to be controlled by the combination of low dose amiodarone (100-200 mg) with procainamide until he died of congestive heart failure on 9th of May, 1992. We reported a rare adult case with CoA and severe heart failure. Lethal arrhythmias in this case were well controlled by the combined administration of low dose amiodarone with procainamide regardless of severely impaired cardiac function.