1. From the Division of Cardiovascular Medicine (F.H., M.S., R.V., I.S.), Department of Medicine (T.P., E.F.), Division of Pulmonary and Critical Care Medicine (K.T.K., V.d.J.P., R.L.D., R.T.Z.), and Division of Cardiology, Department of Pediatrics (D.N.R.), Stanford University, Stanford, CA; and Department of Anesthesia, Montreal University, Montreal, Quebec, Canada (A.Y.D.).