Background: Thromboembolic complications occur more frequently in patients with chronic heart failure (CHF) than in the general population. Formation of a compact fibrin clot resistant to lysis has been shown in arterial and venous thrombosis.
Objective: To investigate fibrin clot properties in patients with CHF.
Method: Plasma clot permeability, compaction, turbidity and fibrinolysis were assessed in 36 consecutive patients with stable CHF (30M, 6F; aged 64+/-10 years, left ventricular ejection fraction (LVEF) 34.9+/-6.7%) and 36 controls matched for age, sex, cardiovascular risk factors and medication. Exclusion criteria were LVEF >40%, anticoagulant therapy, previous thromboembolic events, atrial fibrillation.
Results: Clots obtained from plasma of patients with CHF had 23% lower clot permeability (p<0.0001), 13% less clot compaction (p<0.001), 15% faster fibrin polymerisation (p<0.0001) and tended to have prolonged fibrinolysis time (p=0.1) compared with controls. C-reactive protein and fibrinogen were associated inversely with clot permeability (R(2)=0.84, p<0.0001 and R(2)=0.79, p<0.0001, respectively) and positively with fibrinolysis time (R(2)=0.88, p<0.0001 and R(2)=0.80, p<0.0001, respectively) in patients with CHF. Plasma thrombin-antithrombin complex concentrations were inversely correlated with clot permeability (R(2)=0.88, p<0.0001) and positively with fibrinolysis time (R(2)=0.91, p<0.0001). Left atrium diameter, but not LVEF, correlated with fibrinolysis time (R(2)=0.61, p=0.027).
Conclusions: Patients with CHF with sinus rhythm are characterised by faster formation of compact plasma fibrin clots, which might predispose to thromboembolic complications.