[1] Keele Univ, Ctr Prognosis Res, Keele Cardiovasc Res Grp, Keele, England
[2] Univ Hosp UK, Cardiff, Wales
[3] Univ Hosp Birmingham NHS Fdn Trust, Birmingham, England
[4] Univ Southampton, Coronary Res Grp, Southampton, England
[5] Westmead Hosp, Dept Cardiol, Sydney, NSW, Australia
[6] Univ Sydney, Westmead Appl Res Ctr, Sydney, Australia
[7] Thomas Jefferson Univ, Dept Med, Philadelphia, PA 19107 USA