[1] Univ Utrecht, Univ Med Ctr Utrecht, Div Heart & Lungs, Dept Cardiol, E03-511,POB 85500, NL-3508 GA Utrecht, Netherlands
[2] Netherlands Heart Inst, Utrecht, Netherlands
[3] Cent Mil Hosp, Utrecht, Netherlands
[4] UCL, Hlth Data Res UK, London, England
[5] UCL, Inst Hlth Informat, London, England
[6] UCL, Fac Populat Hlth Sci, Inst Cardiovasc Sci, London, England