Author information: (1)Department of Cardiovascular Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-Cho, Kita-Ku, Okayama, 700-8558, Japan. eziken82@gmail.com. (2)Department of Internal Medicine, Tamano City Hospital, Tamano, Japan. eziken82@gmail.com. (3)Department of Cardiovascular Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-Cho, Kita-Ku, Okayama, 700-8558, Japan. miyoshit@cc.okayama-u.ac.jp. (4)Department of Internal Medicine, Kihara Cardiovascular Clinic, Asahikawa, Japan. (5)Department of Cardiology, Minamino Cardiovascular Hospital, Hachioji, Japan. (6)Department of Internal Medicine, Iwasa Hospital, Gifu, Japan. (7)Department of Cardiology, Mitoyo General Hospital, Kanonji, Japan. (8)Department of Cardiovascular Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-Cho, Kita-Ku, Okayama, 700-8558, Japan. (9)Department of Internal Medicine, Okayama East Neurosurgery Hospital, Okayama, Japan. (10)Department of Cardiology, Okayama Rosai Hospital, Okayama, Japan. (11)Department of Cardiovascular Medicine, Specified Clinic of Soyokaze Cardiovascular Medicine and Diabetes Care, Matsuyama, Japan. (12)Department of Internal Medicine, Akaiwa Medical Association Hospital, Akaiwa, Japan. (13)Department of Cardiovascular Medicine, Iwakuni Clinical Center, Iwakuni, Japan. (14)Department of Internal Medicine, Minagawa Cardiovascular Clinic, Gifu, Japan. (15)Department of Cardiovascular Medicine, Okayama City Hospital, Okayama, Japan. (16)Department of Internal Medicine, Yoshinaga Hospital, Bizen, Japan. (17)Department of Cardiovascular Medicine, Japanese Red Cross Okayama Hospital, Okayama, Japan. (18)Department of Cardiology, Fukuyama City Hospital, Fukuyama, Japan.