1. From the Department of Radiology (U.H., F.M., R.C.C., M.F., S. Abbara, T.J.B., S. Achenbach) and the Division of Cardiology (F.M., I.-k.J., L.J.D., S. Achenbach), Massachusetts General Hospital, Boston, Mass, and the Department of Internal Medicine II (S. Achenbach), University of Erlangen, Erlangen, Germany.