1. From the Department of Cardiology, Gelre Hospital, Apeldoorn, the Netherlands (L.C., R.L.B., R.A.W.); Department of Cardiothoracic Surgery, AZ Sint-Jan, Brugge, Belgium (M.A.A.M.S.); Center for Medical Genetics, Ghent University Hospital, Ghent, Belgium (B.L.L.); Department of Pathology, St Antonius Hospital, Nieuwegein, the Netherlands (M.F.M.O.); and Departments of Clinical Genetics (D.Q.C.M.B.-S.) and Cardiology (B.J.M.M.), Academic Medical Centre, Amsterdam, the Netherlands.