1. Division of Cardiology, UPMC Heart and Vascular Institute, University of Pittsburgh Presbyterian Hospital, 200 Lothrop Street, Pittsburgh, PA 15213, USA
2. Department of Critical Care Medicine, University of Pittsburgh Presbyterian Hospital, 200 Lothrop Street, Pittsburgh, PA 15213, USA
3. Safar Center for Resuscitation Research, University of Pittsburgh Presbyterian Hospital, 200 Lothrop Street, Pittsburgh, PA 15213, USA