1. Comprehensive Heart Failure Center, University Hospital Würzburg , Am Schwarzenberg 15, Haus A15, 97078 Würzburg , Germany
2. Department of Internal Medicine I, University Hospital Würzburg , Oberdürrbacher Str. 6, 97080 Würzburg , Germany
3. Division of Cardiology, Department of Internal Medicine, University Heart Center, Medical University of Graz , Auenbrugger Platz 15, 8036 Graz , Austria