[1] Harvard Univ, Sch Med, Beth Israel Deaconess Med Ctr, Div Cardiovasc,Dept Med, Boston, MA 02215 USA
[2] Kings Coll Hosp London, London, England
[3] Harvard Univ, Sch Med, Brigham & Womens Hosp, Dept Med,Div Cardiovasc, Boston, MA 02215 USA
[4] Foothills Prov Gen Hosp, Dept Med Calgary, Calgary, AB T2N 2T9, Canada
[5] Duke Univ, Med Ctr, Dept Med, Div Cardiol, Durham, NC 27710 USA
[6] Stanford Univ, Dept Med, Stanford, CA 94305 USA
[7] Univ Birmingham, City Hosp, Ctr Cardiovasc Sci, Birmingham, W Midlands, England
[8] Baylor Coll Med, Emergency Dept, Houston, TX 77030 USA
[9] Univ Maryland, Sch Med, Anne Arundel Hlth Syst Res Inst, Anne Arundel Med Ctr, Baltimore, MD 21201 USA
[10] Corp Sanitaria I Univ Parc, Tauli Hosp Sabadell Parc Tauli, Crit Care Ctr, Barcelona, Spain