1. Division of Cardiology, University Heart Center Zurich, Rämistrasse 100, CH-8091 Zurich, Switzerland
2. Division of Cardiology, Johns Hopkins Hospital, 1800 Orleans St, Baltimore, MD 21287, USA
3. Leon H Charney Division of Cardiology, New York University School of Medicine, 550 1st Avenue, New York, NY 10016, USA
4. Center for Integrative Human Physiology, University of Zurich, Rämistrasse 71, Zurich 8006, Switzerland