1. From the Wallace H. Coulter Department of Biomedical Engineering at Georgia Institute of Technology and Emory University, Atlanta, GA (N.S., S.L., A.P.Y.); Emory University, Department of Medicine, Division of Cardiology (G.K., F.J.S., S.L.); and Atlanta VA Medical Center, Department of Medicine, Division of Cardiology, Decatur, GA (G.K.).