1 Division of Cardiology, Duke University School of Medicine, Durham, North Carolina, USA; Duke Clinical Research Institute, Durham, North Carolina, USA. Electronic address: stephen.greene@duke.edu.
2 Division of Cardiology, Duke University School of Medicine, Durham, North Carolina, USA; Duke Clinical Research Institute, Durham, North Carolina, USA.
3 Division of Emergency Medicine, Duke University School of Medicine, Durham, North Carolina, USA.
4 Department of Biostatistics and Bioinformatics, Duke University School of Medicine, Durham, North Carolina, USA.
5 Division of Cardiology, Duke University School of Medicine, Durham, North Carolina, USA.
6 Department of Emergency Medicine, Indiana University School of Medicine, Indianapolis, Indiana, USA.