1. Department of Cardiology, Heart and Lung Centrum; Leiden University Medical Centre; Albinusdreef 2 2333 ZA Leiden the Netherlands
2. Department of Cardiology; AHEPA University Hospital; Thessaloniki Greece
3. Department of Cardiology; Thoraxcenter, Erasmus Medical Centre; Rotterdam the Netherlands
4. Department of Cardio-Thoracic Surgery; Erasmus Medical Centre; Rotterdam the Netherlands
5. Columbia University Medical Center and The Cardiovascular Research Foundation; New York NY USA