Primary Prevention of Sudden Cardiac Death in Patients with Ischemic Heart Disease —Possible Role of the Shock Device in the Asia—

Recently several randomized trials have demonstrated the excellent role of the implantable cardioverter-defibrillator (ICD) in improving the mortality rate in patients with a high risk of sudden cardiac death regardless of its purpose or the underlying heart disease. However, because such large clinical trials have only been carried out in Western countries, those results may not be fully applicable to Japanese or other Asian patient populations.According to a Japanese study, the total mortality in the patients was approximately 20% during 5 years of follow up, which was comparable to, or slightly better than that in the MADIT-II patients with ICDs. In such a patient population with an excellent prognosis, the MADIT-II criteria can not easily be applied. Therefore, we should strengthen the criteria, i.e. from an EF ≤ 35% to 25% or adopt the usage of additional examinations (e.g. signal averaging ECG, micro-volt T wave alternance or EPS).