1. Essen Medical Associates, Bronx, NY, U.S.A.
2. Department of Medicine, Division of Cardiology, Westchester Medical Center/New York Medical College, Valhalla, NY, U.S.A.
3. Department of Medicine, Elmurst Hospital Medical Center, Queens, NY, U.S.A.
4. Albert Einstein College of Medicine, Bronx, NY, U.S.A.