1. Department of Cardiovascular Medicine (J.C.J.), Mayo Clinic, Rochester, MN.
2. Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine (J.C.J.), Mayo Clinic, Rochester, MN.
3. Department of Critical Care Medicine and Division of Cardiology, Department of Medicine, University of Alberta Hospital, Edmonton, Canada (S.v.D.).
4. The Carl and Edyth Lindner Center for Research and Education at the Christ Hospital Health Network, Cincinnati, OH (T.D.H.).