1 Department of Cardiology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands.
2 Department of Cardiology, Presbyterian Hospital/Columbia University Irving Medical Center, 177 Fort Washington Ave, New York, NY 10032, USA.
3 Department of Cardiology III-Adult Congenital and Valvular Heart Disease, University Hospital Muenster, Albert-Schweitzer-Campus 1, Building A1, Muenster 48149, Germany.