The levels of FXI are associated with altered fibrin clot properties and thrombin generation in patients with acute decompensated HFrEF and sinus rhythm: a preliminary study

Background Acute decompensated heart failure (ADHF) is a complex clinical condition associated with an increased risk of thromboembolic events. Chronic heart failure with reduced ejection fraction (HFrEF) is linked to alterations in the fibrin clot properties. Coagulation factor XI (FXI) is crucial for thrombus enlargement during hemostasis and its association with the modification of fibrin clot properties which was observed in several cardiovascular disorders. Moreover, recently FXI inhibitors have emerged as an alternative for current oral anticoagulants. Purpose Therefore we sought to analyze whether the levels of FXI in patients with ADHFrEF and sinus rythm has influence on the fibrin clot properties and thrombin generation. Methods We enrolled 69 consecutive adult patients diagnosed with ADHFrEF and sinus rythm. We recorded demographic and anthropometric data along with the medical history, routine laboratory results and the echocardiographic parameters. The serum FXI levels were assayed using ELISA method. Fibrin clot parameters including clot permeability (Ks) and lysis time (CLT) were evaluated. Thrombin generation was reflected by endogenous thrombin potential (ETP). Results In the 35 patients (50.7%) FXI was >600 ng/mL, whereas 34 (49.3%) had FXI <600 ng/ml. Patients with FXI>600 ng/mL were comparable to remainders in terms of demographic and anthropometric parameters, comorbidities and routine laboratory examinatoions with exception for lower by 21.5% creatinine levels. Noteworthy, they had lower by 13.6% Ks values (P=0.026) and higher by 20.8% ETP (P=0.011) as well as higher by 20.0% peak thrombin generation (P=0.007) levels. By multivariable analysis, after adjustment for fibrinogen levels and renal failure, we observed that FXI levels and right atrial area were independenlty associated with Ks (R2=0.311, P<0.001) while FXI levels, pulmonary trunk diameter, left ventricle end-diastolic volume and INR were correlated with ETP (R2=0.320, P<0.001). Conclusions The current study presented that the levels of FXI are associated with alteration of fibrin clot parameters and thrombin generation in patients with ADHFrEF and sinus rythm. We observed that subjects with ADHFrEF and FXI> 600 ng/mL were characterized by more dense fibrin clots and higher ETP levels.