This study investigated the clinical course of arrhythmogenic right ventricular cardiomyopathy (ARVC) patients and in particular evaluated the contribution of radiofrequency catheter ablation (RFCA) and an implantable cardioverter-defibrillator (ICD) to the treatment of ARVC. ARVC is a myocardial disorder and a cause of sudden cardiac death due to ventricular tachycardia (VT). Little is known about its prognosis in Japanese ARVC patients. Thirty-five ARVC patients were studied. Mean age of patients whose onset of ARVC was congestive heart failure (CHF) (66.0 +/- 4.0 years) was significantly higher than those whose onset was VT (44.5 +/- 14.8 years, P < 0.05). ARVC patients with CHF onset showed significantly higher death rates compared to those with VT onset. ICD treatment significantly reduced episodes of hospitalization due to VT (0.1 +/- 0.4 episodes) in comparison to treatment by RFCA (1.7 +/- 2.2 episodes, P < 0.03). RFCA treatment did not reduce recurrence of VT in the follow-up period. ICD therapy showed comparable mortality to RFCA treatment. The prognosis of ARVC with CHF onset is poor. ICD therapy significantly reduced hospitalization due to VT compared with RFCA treatment. ICD implantation in combination with medication may be a better treatment for ARVC.