1. Section of Cardiology, Department of Internal Medicine, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA
2. Division of Epidemiology, Department of Public Health Sciences, University of Miami, Miami, Florida, USA
3. Division of Cardiology, Department of Medicine, Albert Einstein College of Medicine, Bronx, New York, USA
4. Department of Biostatistical Sciences, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA