1. Division of Cardiology, Department of Internal Medicine, St. Marianna University School of Medicine, Kawasaki-city, Kanagawa-prefecture, 216-8511, Japan;
2. Kerckhoff Heart and Thorax Center, Department of Cardiology, 61231 Bad Nauheim, Germany
3. Department of Anatomy and Cell Biology, Wakayama Medical University School of Medicine, Wakayama-city, Wakayama-prefecture, 641-0012, Japan