Clot lysis time in patients with end-stage heart failure on mechanical circulatory support: long-term observation

Abstract

Abstract Introduction Despite being on antithrombotic therapy patients with left ventricular assist devices (LVAD) are susceptible to thromboembolic events. Therefore, we investigated whether LVAD has an influence on the fibrinolytic capacity of the plasma. The aim of the study was to assess the clot lysis time (CLT) in the course of time in LVAD patients and the connection between CLT and adverse events in this group of patients. Materials and Methods We investigated end-stage HF patients scheduled for LVAD (n=85, men 90.6%; age 48.6–63.8 years) at four consecutive time points: prior to LVAD implantation, 3–4 months, 6–12 months, and then every 6 months; the CLT was determined in the first three blood samples and the last, at the end of observation (no longer than 5 years after implantation). Enrolled for further analyses were patients who completed four observations, n=23. MACCE were defined as all-cause mortality, ischemic stroke and TIA, peripheral/pulmonary embolism, and pump thrombosis. NACE included MACCE and bleeding complications. Results Patients with HF showed longer CLT median [IQR], when compared to reference values: 111.25 [97–300] vs. 84.8 [75.0–98.5] min, P<0.001. MACCE occurred in 36.5% pts, bleeding events in 25.9% pts and NACE in 62.4% pts. Deaths occurred in 31.8% pts. Patients without NACE during the whole observation period showed shortened CLT in the last long-term observation P=0.025. Conclusions This study is the first to show that patients scheduled for LVAD are characterized by prothrombotic fibrin clot properties. The CLT value in long-term observation is lower in patients without NACE.