1. Department of Cardiology Keio University School of Medicine Tokyo Japan
2. Department of Cardiology Saiseikai Utsunomiya Hospital Tochigi Japan
3. Department of Cardiovascular Surgery Keio University School of Medicine Tokyo Japan
4. Department of Cardiology New Tokyo Hospital Matsudo Japan
5. Department of Cardiology Osaka City General Hospital Osaka Japan
6. Department of Cardiology Saiseikai Yokohama‐City Eastern Hospital Yokohama Japan
7. Department of Cardiology Sendai Kousei Hospital Sendai Japan
8. Department of Cardiology Shonan Kamakura General Hospital Kamakura Japan
9. Department of Cardiology Kokura Memorial Hospital Kokura Japan
10. Department of Cardiovascular Surgery Tokyo Bay Urayasu‐Ichikawa Medical Center Chiba Japan
11. Department of Cardiology Toyama University Hospital Toyama Japan
12. Department of Cardiology Ogaki Municipal Hospital Gifu Japan
13. Department of Cardiology Teikyo University School of Medicine Tokyo Japan
14. Department of Cardiology Toyohashi Heart Center Toyohashi Japan
15. Department of Cardiology Nagoya Heart Center Nagoya Japan