Department of Cardiovascular Medicine, Saga University, 5-1-1 Nabeshima, Saga, 849-8501, Japan. tanakaa2@cc.saga-u.ac.jp. Department of Cardiovascular Medicine, Dokkyo Medical University School of Medicine, Mibu, Japan. Department of Medical Statistics, Graduate School of Medicine, Osaka City University, Osaka, Japan. Department of Cardiology, Tokyo Medical University, Tokyo, Japan. Division of Cardiology, Yokohama City University Medical Center, Yokohama, Japan. Department of Cardiology, Nagoya University Graduate School of Medicine, Nagoya, Japan. Department of Cardiology, Osaka Medical and Pharmaceutical University, Takatsuki, Japan. Onishi Heart Clinic, Tsu, Japan. Department of Cardiology, Moriyama Memorial Hospital, Tokyo, Japan. Division of Cardiology, Osaka Rosai Hospital, Sakai, Japan. Department of Cardiovascular Medicine, Osaka University Graduate School of Medicine, Osaka, Japan. Department of Cardiovascular Medicine, Saga University, 5-1-1 Nabeshima, Saga, 849-8501, Japan.