1. Division of Cardiovascular Disease (N.S.S., V.P., G.A., P.A.), University of Alabama at Birmingham.
2. Department of Medicine (A.H.), University of Alabama at Birmingham.
3. Division of Cardiology, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas (A.P.).
4. Section of Cardiology, Birmingham Veterans Affairs Medical Center, AL (P.A.).