1. The Permanente Medical Group, Kaiser Permanente Santa Clara Medical Center, Santa Clara, CA (D.C.L.)
2. Cedars-Sinai Heart Institute (S.C., E.P.-B., D.H., M.N., R.M., S.K., B.C., S.W.T., T.D.H.)
3. Department of Emergency Medicine (S.T., J.G., N.M.), Cedars-Sinai Medical Center, Los Angeles, CA
4. Department of Emergency Medicine, UCLA Olive View Medical Center, Los Angeles, CA (I.R.).