1. From the Philadelphia Veterans Affairs Medical Center/University of Pennsylvania (J.A.C., M.S.J.-S.), Philadelphia, PA; Institute Biomedical Technology (P.S.) and Departments of Cardiovascular Diseases (T.C.G., M.L.D.B., E.R.R.) and Public Health (D.D.B., E.R.R.), Ghent University Hospital, Ghent, Belgium; Baylor College of Medicine (A.K.G.), Houston, TX.