1. Department of Cardiology, Deborah Heart and Lung Center, Browns Mills, NJ, US
2. Division of Cardiology, Department of Internal Medicine, Ahmanson/UCLA Adult Congenital Heart Disease Center, University of California, Los Angeles, CA, US
3. Keele Cardiovascular Research Group, Centre for Prognosis Research, Keele University, Keele, UK
4. Division of Cardiology, Department of Internal Medicine, Northside Cardiovascular Institute, Northside Hospital, Atlanta, GA, US