1. Section of Cardiac Pacing and Electrophysiology, Division of Cardiology, Cleveland Clinic , J2-2, 9500 Euclid Avenue, Cleveland, OH 44195 , USA
2. Section of Electrophysiology, Montefiore Medical Center , New York, NY , USA
3. Texas Cardiac Arrhythmia Institute, St. David’s Medical Center , Austin, TX , USA