[1] Kyoto Univ, Grad Sch Med, Dept Cardiovasc Med, Sakyo Ku, Kyoto 6068507, Japan
[2] Kinki Univ, Sch Med, Ctr Gen Internal Med & Emergency Care, Osaka 589, Japan
[3] Tenri Hosp, Div Cardiol, Tenri, Nara 632, Japan
[4] Kobe City Med Ctr, Gen Hosp, Dept Cardiovasc Med, Kobe, Hyogo, Japan
[5] Kyoto Univ, Grad Sch Med, Dept Cardiovasc Surg, Kyoto, Japan
[6] Japanese Red Cross Soc, Wakayama Med Ctr, Dept Cardiovasc Surg, Wakayama, Japan
[7] Kobe City Med Ctr, Gen Hosp, Dept Cardiovasc Surg, Kobe, Hyogo, Japan
[8] Kishiwada City Hosp, Dept Cardiovasc Surg, Kishiwada, Japan
[9] Kumamoto Univ, Grad Sch Med Sci, Dept Cardiovasc Surg, Kumamoto, Japan
[10] Univ Fukui, Fac Med Sci, Dept Cardiovasc Surg, Fukui 910, Japan
[11] Mitsubishi Kyoto Hosp, Dept Cardiovasc Surg, Kyoto, Japan
[12] Hamamatsu Rosai Hosp, Dept Cardiovasc Surg, Hamamatsu, Shizuoka, Japan
[13] Tenri Hosp, Div Cardiovasc Surg, Tenri, Nara 632, Japan
[14] Kagoshima Univ, Grad Sch Med & Dent Sci, Dept Cardiovasc Surg, Kagoshima 890, Japan