Thrombin generation, fibrin clot permeation and lysis in patients with severe mitral regurgitation undergoing transcatheter edge-to-edge mitral valve repair: Mitral Fibrin Study.

The intricate management of heart failure (HF), especially in the context of reduced ejection fraction, is compounded by an elevated risk of thromboembolic events. Existing studies offer inconclusive insights into the interplay between MR and the coagulation system. This study aimed to investigate the impact of transcatheter edge-to-edge repair (TEER) on specific coagulation parameters in HF patients. A cohort of 31 HF patients with severe MR undergoing TEER underwent systematic evaluation at three time points (V1, V2, and V3). Coagulation parameters, including fibrinogen concentration, thrombin generation, fibrin clot permeability (Ks), and clot lysis time (CLT), were assessed (n = 27 [V2], and n = 25 [V3]). TEER induced changes in fibrinogen levels (P = 0.01, V3 vs. V2) and improved fibrin clot properties over a 50-day follow-up (Ks, P = 0.01, V3 vs. V2). No significant differences were observed among time points in analyzed blood clot parameters. Correlation analysis showed that baseline CLT was significantly associated with delta NT-proBNP, (P = 0.049; r = 0.40). Multivariable analysis demonstrated that baseline CLT was an independent predictor of the early post-TEER NT-proBNP change (R2 = 0.55, P = 0.02). We found that fibrinogen levels decreased, and permeation coefficient increased over a median 50-day post-TEER follow-up, compared to early post-procedure assessments. Other blood coagulation parameters remained unchanged from baseline to both follow-up periods after TEER. Finally, CLT was an independent predictor of early NT-proBNP increase, emphasizing its role as an indicator of the hemodynamic response to TEER.