[1] Univ Hosp Zurich, Dept Angiol, CH-8091 Zurich, Switzerland
[2] Johannes Gutenberg Univ Mainz, Ctr Thrombosis & Hemostasis, Mainz, Germany
[3] Univ Southern Denmark, Danish Hosp Rheumat Dis, Sonderborg, Denmark
[4] Univ Southern Denmark, Dept Reg Hlth Res IRS, Odense, Denmark
[5] Guys & St Thomas NHS Fdn Trust, Thrombosis & Haemostasis, London, England