Affiliation: | 1. Section of Cardiac Electrophysiology and Pacing, Heart and Vascular Institute, The Cleveland Clinic Foundation, , Cleveland, Ohio;2. St. Jude Medical, , Sunnyvale, California;3. Southeastern Cardiovascular Institute, , Rome, Georgia;4. Iowa Heart Center, , Des Moines, Iowa;5. Parkview Research Center, , Fort Wayne, Indiana;6. Arkansas Heart Hospital, , Little Rock, Arkansas |