1. From the Research Center and Departments of Surgery (R.G.D., S.F., R.C., M.P., Y.H., D.B., P.P., M.C., L.P.P.), Anesthesiology (R.M.), and Biostatistics (A.F.), Montreal Heart Institute, Montreal, Quebec, Canada, and the Cardiovascular Surgery Unit, Arnaud de Villeneuve Teaching Hospital, Montpellier, France (R.G.D.).