1. University Hospital Basel; University of Basel; Switzerland
2. Knappschaftskrankenhaus, Klinikum Westfalen; Dortmund Germany
3. University Hospital Saarland; Homburg Germany
4. Central Clinic; Bad Berka Germany
5. University Hospital for Cardiology, Heart Center Leipzig; Germany
6. Cantonal Hospital St; Gallen Switzerland
7. University Hospital Ulm; Germany
8. Cantonal Hospital Luzern; Switzerland
9. Cantonal Hospital Baselland; Liestal Switzerland
10. University Hospital Jena; Germany
11. Medical University Graz; Austria
12. Charité University Hospital; Berlin Germany
13. Heart Center Brandenburg; Bernau Germany
14. Unfallkrankenhaus Berlin; Germany