1. Department of General and Interventional Cardiology; University Heart Center Hamburg-Eppendorf; Hamburg Germany
2. Department of Cardiology; Medical University of Graz; Graz Austria
3. Department of Cardiothoracic Surgery; Medical University of Graz; Graz Austria
4. Department of Cardiology; Leiden University Medical Center; Leiden the Netherlands
5. Department of Cardiology; Charit e-Universitaetsmedizin Berlin; Campus Virchow-Klinikum; Berlin Germany