1. Section of Electrophysiology, Division of Cardiology, University of California San Diego , La Jolla, CA , USA
2. Division of Cardiovascular Medicine, West Virginia University Heart & Vascular Institute , Morgantown, WV , USA
3. Division of Cardiology, University of Oklahoma Health Sciences Center , Oklahoma, OK , USA
4. Division of Cardiovascular Medicine, Oregon Health and Science University , Portland, OR , USA
5. Division of Cardiovascular Medicine, University of California Davis , Sacramento, CA , USA