Division of Cardiology, Duke University School of Medicine, Durham, North Carolina. Duke Clinical Research Institute, Durham, North Carolina. Division of Cardiovascular Medicine, Brigham and Women's Hospital, Boston, Massachusetts. Instituto Cardiovascular de Rosario, Estudios Clínicos Latino América, Rosario, Argentina. Cardiovascular Research Centre, British Heart Foundation, Cardiovascular Research Centre, University of Glasgow, Glasgow, United Kingdom. Department of Medical and Surgical Specialties, University of Brescia, Brescia, Italy. Division of Cardiovascular Medicine, University of Minnesota, Minneapolis. Division of Cardiology, Universidad da Coruña, A Coruña, Galicia, Spain. Department of Cardiology, Linköping University Hospital, Linköping, Sweden. Department of Cardiology, Odd. Srdcovehozlyhavania a Transplantacie, Bratislava, Slovakia. Division of Cardiology, Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada. Heart Transplant Unit, St. Vincent's Hospital Sydney, Darlinghurst, NSW, Australia. Emergency Cardiology Department, Ukranian Strazhesko Institute of Cardiology, Kiev, Ukraine. Cardiology Department, St. John of God Hospital, Budapest, Hungary. Amgen, Inc, Thousand Oaks, California. Clinical Research, Cytokinetics, South San Francisco, California. Research and Development, Cytokinetics, South San Francisco, California. Division of Cardiology, San Francisco VA Medical Center, San Francisco, California. Division of Cardiology, University of California San Francisco, San Francisco.