1. Center for Advanced Cardiac Care, Division of Cardiology, New York Presbyterian-Columbia University Irving Medical Center, New York (E.M. DeFilippis, E.M. Donald).
2. Heart and Vascular Institute, Cleveland Clinic, OH (K.H.).
3. Duke University Medical Center, Durham, NC (K.F.R., R.A.).
4. Division of Cardiology, University of California San Diego Medical Center (H.S., K.N.H.).
5. Division of Cardiovascular Medicine, Department of Medicine, Stanford University School of Medicine, CA (K.K.K.).
6. Vanderbilt Heart and Vascular Institute, Vanderbilt University Medical Center, Nashville, TN (L.P.).
7. Department of Cardiology, Smidt Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA (M.M.K.).