1. From the Institute of Diagnostic and Interventional Radiology (L.A.C., M.E., R.M.), Department of Cardiology, University Heart Center (C.T., R.M.), and Department of Cardiac Surgery (P.R.V.), University Hospital Zurich, Raemistrasse 100, 8091 Zurich, Switzerland; and Department of Radiology, Cardiovascular Imaging Unit, IRCCS San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy (L.A.C., H.A.).