[1] Univ Hosp Copenhagen, Rigshosp, Dept Cardiothorac Surg, Copenhagen, Denmark
[2] Univ Hosp Copenhagen, Rigshosp, Dept Cardiol, Copenhagen, Denmark
[3] Univ Copenhagen, Dept Clin Med, Copenhagen, Denmark
[4] Haukeland Hosp, Dept Heart Dis, Bergen, Norway
[5] Univ Bergen, Bergen, Norway
[6] Soder Sjukhuset, Dept Cardiol, Stockholm, Sweden
[7] Karolinska Inst, Dept Mol Med & Surg, Stockholm, Sweden
[8] Linkoping Univ, Dept Cardiothorac & Vasc Surg, Heart Ctr, Dept Hlth Med & Caring Sci, Linkoping, Sweden
[9] Univ Montreal, Montreal Heart Inst, Montreal, PQ, Canada
[10] Univ Iceland, Dept Cardiothorac Surg, Landspitali Univ Hosp, Fac Med, Reykjavik, Iceland
[11] Aalborg Univ, Danish Ctr Clin Hlth Serv Res DACS, Dept Clin Med, Aalborg, Denmark
[12] Aalborg Univ Hosp, Aalborg, Denmark
[13] Karolinska Univ Hosp, Dept Cardiothorac Surg, Stockholm, Sweden
[14] Auckland City Hosp, Cardio Thorac Surg Dept, Green Lane Div, Auckland, New Zealand