[1] Univ Penn, Div Cardiovasc Med, Heart Failure & Cardiac Transplant Program, Philadelphia, PA 19104 USA
[2] VA Ctr Practice Management & Outcomes Res, Ann Arbor, MI USA
[3] Univ Michigan, Ann Arbor, MI 48109 USA
[4] Indiana Univ, St Vincents Hosp, Indianapolis, IN 46204 USA
[5] Sanger Clin PA, Charlotte, NC USA
[6] Sharp Mem Hosp & Rehabil Ctr, San Diego Cardiac Ctr, San Diego, CA USA
[7] Emory Univ, Div Cardiol, Atlanta, GA 30322 USA
[8] Chestnut Hill Cardiol, Flourtown, PA USA
[9] Columbia Univ, Div Circulatory Physiol & Cardiol, New York, NY USA
[10] Brigham & Womens Hosp, Dept Med, Boston, MA 02115 USA
[11] Wyeth Ayerst Res, Philadelphia, PA USA