1. Department of Cardiovascular Medicine/Heart Rhythm Center Tokyo Medical and Dental University Tokyo Japan
2. Cardiovascular Center Tsuchiura Kyodo Hospital Tsuchiura Japan
3. Department of Cardiology Saitama Red Cross Hospital Saitama Japan
4. Cardiovascular Center Yokosuka Kyosai Hospital Yokosuka Japan
5. Division of Cardiology Musashino Red Cross Hospital Tokyo Japan
6. Department of Advanced Arrhythmia Research Tokyo Medical and Dental University Tokyo Japan