1. Division of Cardiology, Department of Internal Medicine, Iwate Medical University School of Medicine, 2-1-1 Idaidori, Yahaba-cho, Shiwa-gun, Iwate Prefecture 028-3695, Japan
2. Department of Thoracic Surgery, Iwate Medical University School of Medicine, 2-1-1 Idaidori, Yahaba-cho, Shiwa-gun, Iwate Prefecture 028-3695, Japan