1. Section of Cardiovascular Medicine, Department of Internal Medicine, Yale School of Medicine, New Haven, CT (S.W.R., K.A.A.C., T.A., N.R.D.).
2. Center for Outcomes Research & Evaluation (X.X., C.S.P., T.A., N.R.D.), Yale-New Haven Hospital, New Haven‚ CT.
3. Department of Pharmacy (R.J.R.), Yale-New Haven Hospital, New Haven‚ CT.
4. Cytokinetics, Incorporated, South San Francisco, CA (P.S.).