1. Department of Rehabilitation, Nagoya University Hospital, Nagoya 466-8560, Japan
2. Department of Rehabilitation, Mie University Hospital, Tsu 514-8507, Japan
3. Department of Cardiology, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan
4. Department of Cardiac Surgery, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan