1. From the Minneapolis Heart Institute Foundation at Abbott Northwestern Hospital, MN (J.H.T., T.D.H., J.F., Y.L.W., I.J.C., D.L.L., J.R.L., W.R.P., N.M.B., A.P., J.L.L., R.F.G.)
2. Cardiovascular Division, The University of Minnesota School of Medicine, Minneapolis (J.H.T., C.M.S.).