1 Kitasato Institute Hospital, Kitasato University, Minato, Tokyo, Japan.
2 Division of Functional Diagnostics, Department of Health Sciences, Osaka University Graduate School of Medicine, 1-7 Yamada-oka, Suita, Osaka, 565-0871, Japan.
3 Tenri Yorozu Hospital, Tenri, Nara, Japan.
4 Saitama Medical University International Medical Center, Hidaka, Saitama, Japan.
5 Hyogo Brain and Heart Center, Himeji, Hyogo, Japan.
6 The University of Tokyo Hospital, Bunkyo, Tokyo, Japan.
7 Gunma Cardiovascular Center, Maebashi, Gunma, Japan.
8 National Cerebral and Cardiovascular Center, Suita, Osaka, Japan.
9 The Sakakibara Heart Institute of Okayama, Okayama, Okayama, Japan.
10 Tokushima University Hospital, Tokushima, Tokushima, Japan.
11 Division of Functional Diagnostics, Department of Health Sciences, Osaka University Graduate School of Medicine, 1-7 Yamada-oka, Suita, Osaka, 565-0871, Japan. nakatani@sahs.med.osaka-u.ac.jp.