1. Department of Cardiovascular Medicine, Fukushima Medical University, Fukushima Medical University, Fukushima, Japan
2. Cardiology Department, Takeda General Hospital, Takeda General Hospital, Aizuwakamatsu, Japan
3. Cardiology Department, Sukagawa Hospital, Sukagawa Hospital, Sukagawa, Japan
4. Department of Cardiovascular Medicine, Ohara General Hospital, Ohara General Hospital, Fukushima, Japan
5. Cardiology Department, Ayase Heart Hospital, Tokyo, Japan
6. Department of Cardiology, Okitama Public General Hospital, Okitama Public General Hospital, Kawanishi, Japan
7. First Department of Internal Medicine, Yamagata University Hospital, Yamagata University Hospital, Yamagata, Japan