[1] Yokohama City Univ, Med Ctr, Div Cardiol, Yokohama, Kanagawa 232, Japan
[2] Natl Cntr Neurol & Psychiat, Dept Epidemiol & Biostat, Tokyo, Japan
[3] Shizuoka Prefectural Gen Hosp, Shizuoka, Japan
[4] Kyoto Univ, Grad Sch Med, Dept Cardiovasc Med, Kyoto, Japan
[5] Surugadai Nihon Univ Hosp, Dept Cardiol Resuscitat & Emergency Cardiovasc Ca, Tokyo, Japan