[1] Yokohama City Univ, Med Cntr, Crit Care & Emergency Med Cntr, Yokohama, Kanagawa 232, Japan
[2] Yokohama City Univ, Med Cntr, Div Cardiol, Yokohama, Kanagawa 232, Japan
[3] Kyoto Univ, Hlth Serv, Kyoto, Japan
[4] Kokushikan Univ, Tokyo, Japan
[5] Natl Cntr Neurol & Psychiat, Dept Epidemiol & Biostat, Tokyo, Japan
[6] Shizuoka Prefectural Gen Hosp, Hosp Deputy, Shizuoka, Japan
[7] Kyoto Univ, Grad Sch Med, Dept Cardiovasc Med, Kyoto, Japan
[8] Nihon Univ, Sch Med, Dept Cardiol Resuscitat & Emergency Cardiovasc Ca, Surugadai Nihon Univ Hosp, Tokyo, Japan