1. Cardiology Division, Massachusetts General Hospital Harvard Medical School Boston MA USA
2. Department of Medicine, Graduate School Kyung Hee University Seoul South Korea
3. Department of Cardiovascular Medicine Kyung Hee University Seoul South Korea
4. Department of Cardiovascular Medicine Nara Medical University Kashihara Nara Japan
5. Division of Biostatistics, Massachusetts General Hospital Harvard Medical School Boston MA USA
6. Department of Cardiovascular Medicine Kitasato University School of Medicine Sagamihara Kanagawa Japan