1 Department of Cardiovascular Medicine, Osaka Metropolitan University Graduate School of Medicine, 1-4-3 Asahimachi, Abeno-Ku, Osaka, 545-8585, Japan.
2 Department of Cardiovascular Medicine, Osaka Metropolitan University Graduate School of Medicine, 1-4-3 Asahimachi, Abeno-Ku, Osaka, 545-8585, Japan. zakitaka0614@yahoo.co.jp.
3 Department of Medical Statistics, Osaka Metropolitan University Graduate School of Medicine, Osaka, Japan.
4 Department of Cardiovascular Medicine, Kashiwara Municipal Hospital, Osaka, Japan.
5 Department of Cardiovascular Medicine, Ishikiri Seiki Hospital, Osaka, Japan.