1. Department of Medicine, Emory University School of Medicine, 101 Woodruff Circle, Woodruff Memorial Building, Atlanta, GA 30322, USA
2. Department of Internal Medicine, Wake Forest School of Medicine, Medical Center Blvd, Winston-Salem, NC 27157, USA
3. Department of Internal Medicine, Section on Cardiology, Wake Forest School of Medicine, Medical Center Blvd, Winston-Salem, NC 27157, USA
4. Epidemiological Cardiology Research Center, Wake Forest School of Medicine, Medical Center Blvd, Winston-Salem, NC 27157, USA