1. From the Division of Cardiology, Emory University School of Medicine (J.J.K., S.L., K.M.L., S.I.D., D.G.H., Y.R., Z.S.G.), and the Wallace Coulter Emory University/Georgia Institute of Technology Department of Biomedical Engineering (C.J., R.M., H.-J.S., Z.S.G.), Atlanta, Ga.