1. Division of Cardiology, Department of Internal Medicine, UTSW Medical Center, Dallas, TX (A.P., N.K., K.V.P., C.A., S.S., I.J.N., J.D.B.).
2. Department of Medicine, University of Mississippi Medical Center, Jackson (M.E.H., S.K.M., C.B., A.C., J.B.).
3. Division of Cardiology, Duke Clinical Research Institute, Durham, NC (R.J.M.).
4. Division of Cardiology, Emory University School of Medicine, Atlanta, GA (H.K.).
5. Department of Radiology, Vanderbilt University Medical Center, Nashville, TN (J.G.T.).