1. Department of Neurology, Duke University Hospital (S. Shah, Y.X.), Durham, NC.
2. Duke Clinical Research Institute (S. Shah, Y.X., S. Sheng), Durham, NC.
3. Department of Emergency Medicine (K.S.Z.), Massachusetts General Hospital, Boston.
4. Department of Neurology (J.L.S.), UCLA Medical Center, Los Angeles, CA.
5. Department of Neurology, Yale School of Medicine, New Haven, CT (K.N.S.).
6. Division of Cardiology (G.C.F.), UCLA Medical Center, Los Angeles, CA.
7. Department of Neurology (L.H.S.), Massachusetts General Hospital, Boston.
8. Department of Clinical Neurosciences, Hotchkiss Brain Institute, University of Calgary, AB, Canada (E.E.S.).