Background: Indications of implantable cardioverter-defibrillator (ICD) for patients with an old myocardial infarction (OMI) and left ventricular dysfunction (LVD) were expanded in Western countries after the results of MADIT II. However, the prognosis of OMI patients with LVD and the merits of prophylactic implantation of ICD, based on evidence in Japan, have not yet been clarified. This subanalysis of the Japanese Coronary Artery Disease (JCAD) Study focused on MADIT II-compatible patients to clarify the prognosis of OMI patients with LVD in Japan.
Methods and results: Consecutive 6,868 OMI patients were prospectively followed up for 3 years or until clinical events occurred. 291 patients had left ventricular ejection fraction (LVEF) ≤30%. Clinical events, congestive heart failure, cardiopulmonary arrest on arrival and vascular events were significantly more frequent in patients with LVEF ≤30% than in those with better LVEF. In the LVEF ≤30% group, cardiopulmonary arrest on arrival comprised 33% of all-cause deaths, and the survival curves at 2 years of the LVEF ≤30% group were almost compatible with those of the MADIT II ICD group.
Conclusions: In this subanalysis, LVD was less frequent than in Western countries. The annual death rate in JCAD was better than for the MADIT II ICD group. The prophylactic use of ICD seemed to be less effective than in Western countries but still expected to be useful for OMI patients with LVD in Japan.