1. Institute for Social Medicine, Epidemiology and Health Economics, Charite-Universitätsmedizin Berlin, Luisenstrasse 57, 10117 Berlin, Germany
2. Biotronik, Woermannkehre 1, 12359 Berlin, Germany
3. German Heart Centre Munich, Department of Electrophysiology, Faculty of Medicine, Technische Universität München, Munich, Germany