[1] Niigata Univ, Grad Sch Med & Dent Sci, Niigata 9517510, Japan
[2] Tachikawa Med Ctr, Nagaoka, Niigata, Japan
[3] Shibata Prefectural Hosp, Dept Cardiol, Shibata, Japan
[4] Kido Hosp, Dept Cardiol, Niigata, Japan
[5] Niigata Minami Hosp, Dept Cardiol, Niigata, Japan
[6] Niigata Saiseikai Gen Hosp, Dept Cardiol, Niigata, Japan
[7] Shinrakuen Hosp, Dept Cardiol, Niigata, Japan
[8] Sado Gen Hosp, Dept Cardiol, Niigata, Japan
[9] Nagaoka Chu O Hosp, Dept Cardiol, Nagaoka, Niigata, Japan
[10] Niigata Med Ctr, Dept Cardiol, Niigata, Japan
[11] Niigata Prefectural Cent Hosp, Dept Cardiol, Joetsu, Japan
[12] Chimei Do Hosp, Internal Med, Joetsu, Japan