1. From the Joseph B. Whitehead Department of Surgery, Division of Cardiothoracic Surgery, Carlyle Fraser Heart Center (V.H.T., R.A.G., E.L.J., W.H.W., J.M.C.), The Emory Center for Outcomes Research (ECOR) (W.S.W., W.H.W., S.E.), and the Division of Cardiology, Emory University School of Medicine, Atlanta, Ga.