1. Department of Cardiology, University of Michigan , 1500 East Medical Center Drive, Ann Arbor, 48109 MI , USA
2. Department of Cardiology, University Heart Center Zurich , Raemistrasse 100, Zurich 8091 , Switzerland
3. Corrigan Minehan Heart Center, Massachusetts General Hospital, 55 Fruit St, Boston, 02114 MA, USA
4. Division of Cardiology, Department of Medicine, Medical University of Graz , Graz , Austria
5. Medical College, University of Rzeszów and St. Joseph’s Heart Rhythm Center , Rzeszów , Poland
6. Hannover Heart Rhythm Center, Department of Cardiology and Angiology, Hannover Medical School , Hannover , Germany
7. Cardioangiologisches Centrum Bethanien, Agaplesion Bethanien Krankenhaus , Frankfurt , Germany