1. Heart, Vascular and Thoracic Institute, Cleveland Clinic Foundation, OH (A. Mentias, R.S., P.A., M.D.).
2. Division of Cardiology, Department of Internal Medicine, University of Texas (UT) Southwestern Medical Center, Dallas (E.D.P., N.K., D.J.K., S.G., A.P.).
3. Division of Cardiology, Northwestern University School of Medicine, Chicago, IL (C.Y.).
4. Division of Cardiology, Emory University School of Medicine, Atlanta, GA (A. Morris).
5. Division of Cardiology, University of Colorado Anschutz Medical Campus, Denver (L.A.).
6. Ahmanson Cardiomyopathy Center, University of California, Los Angeles, School of Medicine (G.C.F.).
7. Department of Internal Medicine, UT Medical Branch, Galveston, TX (P.C.).