1. From the Division of Allergy, Pulmonary and Critical Care Medicine (I.M.R., A.R.H., M.E.P., J.H.N.) and Division of Cardiovascular Medicine (E.L.B., R.N.P., P.P.F.), Vanderbilt University Medical Center, Nashville, TN; and Division of Cardiology, Wake Forest Baptist Medical Center, Winston-Salem, NC (D.X.Z.).