1. Department of Cardiovascular Medicine Mayo Clinic Rochester Minnesota USA
2. Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine Mayo Clinic Rochester Minnesota USA
3. The Carl and Edyth Lindner Center for Research and Education at the Christ Hospital Health Network Cincinnati Ohio USA
4. Department of Cardiovascular Medicine Cleveland Clinic Cleveland Ohio USA
5. Sentara Heart Hospital, Advanced Heart Failure Center and Eastern Virginia Medical School Norfolk Virginia USA
6. Department of Critical Care Medicine and Division of Cardiology, Department of Medicine University of Alberta Hospital Edmonton Alberta Canada