1 Department of Cardiology, Hokkaido Cardiovascular Hospital, Sapporo, Japan.
2 Department of Gastroenterology, Sapporo Kyoritsu Gorinbashi Hospital, Sapporo, Japan.
3 Department of Cardiology, Hokkaido Cardiovascular Hospital, Sapporo, Japan; Department of Cardiovascular Biology and Medicine, Juntendo University Graduate School of Medicine, Tokyo, Japan. Electronic address: [email protected].