1. Department of Cardiology, Japanese Red Cross Saitama Hospital , 1-5 Shintoshin, Chuo-ku Saitama 330-8553 , Japan
2. Department of Cardiovascular Medicine, Tokyo Medical & Dental University , 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519 , Japan
3. Department of Cardiology, Shin-yurigaoka General Hospital Furusawa-tsuko , 255, Kawasaki Asao-ku, Kanagawa 215-0026 , Japan
4. Department of Cardiology, Sakakibara Heart Institute , 3-16-1 Asahi-cho, Fuchu-shi, Tokyo 183-0003 , Japan
5. Department of Cardiology, Kobe City Medical Center General Hospital , 2-1-1 Minatojima-minamimachi, Kobe Chuo-ku, Hyogo 650-0047 , Japan
6. Department of Cardiology, Toyohashi Heart Center , 21-1, Oyamacho-Gobutori, Toyohashi, Aichi 441-8071 , Japan
7. Department of Cardiology, Japanese Red Cross Musashino Hospital , 1-26-1, Kyonancho, Musashino, Tokyo 180-8610 , Japan
8. Department of Cardiology, Tokyo Medical Center , 2-5-1, Higashigaoka, Meguro-ku, Tokyo 152-8902 , Japan
9. Department of Cardiovascular Medicine, Jikei University Katsushika Medical Center , 6-41-2, Aoto, Katsushika-ku, Tokyo 125-8506 , Japan
10. Department of Cardiovascular Medicine, Jikei University , 3-19-18, Nishi-Shimbashi, Minato-ku, Tokyo 105-8471 , Japan
11. Department of Cardiovascular Medicine, Tokai University Hachioji Hospital , Ishikawamachi 1838, Hachioji, Tokyo 192-0032 , Japan
12. Department of Cardiovascular Medicine, Tokyo Medical University , 6-7-1 Nishishinjuku, Shinjuku-ku, Tokyo 160-0023 , Japan
13. Department of Clinical Biostatistics, Graduate School of Medical and Dental Sciences, Tokyo Medical & Dental University , 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519 , Japan