1. From the Division of Cardiovascular Diseases, Department of Medicine (R.Y.L.-R., D.A., S.V.P., J.A.T.), Division of Cardiothoracic Surgery, Department of Surgery (R.C.), and Department of Epidemiology, School of Public Health (R.C.), and Division of Cardiothoracic Surgery (D.N., J.K.), University of Alabama at Birmingham; and Section of Heart Failure, Department of Medicine, Cleveland Clinic Foundation, OH (R.C.S.).