1. From Department of Cardiology, Ziekenhuis Oost-Limburg, Genk, Belgium (P.B.B., P.M.V.); Faculty of Medicine and Life Sciences, Hasselt University, Belgium (P.B.B., P.M.V.); Heart Center, Sheba Medical Center, Tel Hashomer, Israel (E.S.); and Cardiac Ultrasound Laboratory, Massachusetts General Hospital, Harvard Medical School, Boston (R.A.L.).