1. Heart Center, Japan Red Cross Yokohama City Bay Hospital Yokohama Japan
2. Department of CardiologyEdogawa Hospital Tokyo Japan
3. Arrhythmia CenterTokyo Medical and Dental University Tokyo Japan
4. Division of Cardiac ElectrophysiologyMethodist DeBakey Heart and Vascular Center Houston Texas
5. Division of Cardiac ElectrophysiologyHouston Methodist Research Institute Houston Texas