1. From the Bayer AG, Cardiovascular Research, Wuppertal, Germany (M.V., V.L., S.H.)
2. Laboratory for Clinical Thrombosis and Haemostasis, Departments of Biochemistry and Internal Medicine, Cardiovascular Research Institute Maastricht, Maastricht University, the Netherlands (M.V., R.v.O., H.t.C., H.M.H.S.)
3. Center for Thrombosis and Hemostasis (CTH), University Medical Center of the Johannes Gutenberg-University Mainz, Germany (H.t.C.)
4. Thrombosis and Hemostasis Program, Division of Hematology and Oncology, Department of Medicine, University of North Carolina at Chapel Hill (N.M.).