[1] Copenhagen Cty Univ Hosp, Dept Med, Lab Cardiol, DK-2600 Glostrup, Denmark
[2] Ullevaal Univ Hosp, Oslo, Norway
[3] Haukeland Hosp, N-5021 Bergen, Norway
[4] Sahlgrens Univ Hosp, Gothenburg, Sweden
[5] Univ Helsinki, Cent Hosp, Helsinki, Finland
[6] Cornell Univ, Med Ctr, New York Hosp, New York, NY 10021 USA