1. Department of cardiology, Saiseikai Central Hospital, Minato-ku, Tokyo, Japan
2. Cardiovascular Center, Sendai Kousei Hospital, Sendai, Miyagi, Japan
3. Kokura Memorial Hospital, Kitakyushu, Fukuoka, Japan
4. Cardiovascular Division, Kansai Rosai Hospital, Nishinomiya, Hyogo, Japan
5. Hyogo College of Medicine, Nishinomiya, Hyogo, Japan
6. Kikuna Memorial Hospital, Yokohama, Kanagawa, Japan
7. Saiseikai Yokohama-City Eastern Hospital, Yokohama, Kanagawa, Japan
8. Tokeidai Memorial Hospital, Sapporo, Hokkaido, Japan
9. Nagoya Kyoritsu Hospital, Nagoya, Aichi, Japan
10. Kyoto University Hospital, Kyoto, Kyoto, Japan
11. Sakakibara Heart Institute, Fuchu, Tokyo, Japan
12. Shin-Koga Hospital, Kurume, Fukuoka, Japan
13. Matsuyama Red Cross Hospital, Matsuyama, Ehime, Japan
14. Juntendo University Nerima Hospital, Nerima, Tokyo, Japan
15. Japanese Red Cross Fukuoka Hospital, Minami-ku, Fukuoka, Japan
16. Kanazawa Medical University Hospital, Kahoku, Ishikawa, Japan
17. Shinshu University Hospital, Matsumoto, Nagano, Japan
18. Tokai University Hospital, Isehara, Kanagawa, Japan
19. Yamagata University Hospital, Iidanishi, Yamagata, Japan