Altered plasma fibrin clot properties and fibrinolysis in patients with multiple myeloma

Background Multiple myeloma (MM) is associated with increased risk of venous and arterial thromboembolism. Formation of denser and poorly lysable fibrin clots is observed in patients with arterial and venous thromboembolism. We investigated fibrin clot properties and their determinants in MM patients. Materials and Methods Ex vivo plasma fibrin clot permeability, turbidity and susceptibility to lysis were evaluated in 106 MM patients at the time of diagnosis vs. 100 age‐ and sex‐matched controls. MM patients had lower clot permeability (Ks), compaction, indicating denser fibrin clots, impaired fibrin polymerization with longer lag phase and lower final turbidity (D−Dmax), combined with hypofibrinolysis reflected by longer lysis time and slower rate of D‐dimer release from fibrin clots (D−Drate) compared with controls (all P