1. From the Division of Cardiothoracic Surgery, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, TX (Y.H.S., S.A.L.)
2. Department of Cardiovascular Surgery, Texas Heart Institute, Houston (Y.H.S., S.A.L.)
3. Department of Pharmacology and Nutritional Sciences (N.R.W., L.A.C.), University of Kentucky, Lexington.
4. Department of Physiology and Saha Cardiovascular Research Center (A.D., H.S.L.), University of Kentucky, Lexington.