[1] Univ Hosp Heidelberg, Dept Cardiol Angiol & Pulmonol, Neuenheimer Feld 410, D-69120 Heidelberg, Germany
[2] Univ Oslo, Ulleval & Inst Clin Sci, Oslo Univ Hosp, Dept Cardiol, Oslo, Norway
[3] Innlandet Hosp Trust, Div Lillehammer, Dept Med, Lillehammer, Norway
[4] Imperial Coll, Royal Brompton & Harefield Hosp, Natl Heart & Lung Inst, Glasgow, Lanark, Scotland
[5] Robertson Ctr Biostat & Clin Trials, Glasgow, Lanark, Scotland
[6] Univ Hull, Castle Hill Hosp, Cottingham, England