[1] Natl Hosp Org, Tokyo Med Ctr, Dept Cardiol, Tokyo, Japan
[2] Keio Univ, Sch Med, Dept Cardiol, Tokyo 1608582, Japan
[3] Univ Tokyo, Dept Healthcare Qual Assessment, Tokyo, Japan
[4] Ashikaga Red Cross Hosp, Dept Cardiol, Ashikaga, Japan
[5] Yokohama Municipal Hosp, Dept Cardiol, Yokohama, Kanagawa, Japan
[6] Hino Municipal Hosp, Dept Cardiol, Hino, Tokyo, Japan