[1] Keio Univ, Sch Med, Dept Cardiol, Tokyo, Japan
[2] Keio Univ Hosp, Clin & Translat Res Ctr, Tokyo, Japan
[3] Univ Tokyo, Grad Sch Med, Healthcare Qual Assessment, Tokyo, Japan
[4] Saiseikai Utsunomiya Hosp, Dept Cardiol, Utsunomiya, Tochigi, Japan
[5] Natl Hosp Org Saitama Natl Hosp, Dept Cardiol, Wako, Saitama, Japan
[6] Japanese Red Cross Ashikaga Hosp, Dept Cardiol, Ashikaga, Tochigi, Japan