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Updated: May 8, 2026

In Vitro Thrombosis Test for Ventricular Assist Devices
Published on: March 21, 2025
Longitudinal assessment of thrombin generation using calibrated automated thrombography in patients with
Agnieszka Kuczaj1, Michał Skrzypek2, Bartosz Hudzik3,4
1Department of Cardiac, Vascular and Endovascular Surgery and Transplantology, Faculty of Medical Sciences in Zabrze, Medical University of Silesia, 41-800 Zabrze, M. C. Skłodowskiej 9, 40-055, Katowice, Poland. akuczaj@sum.edu.pl.
Abstract:
Despite improved survival, patients with advanced heart failure receiving long-term left ventricular assist device (LVAD) support remain at risk of serious complications, including pump thrombosis, ischemic stroke, and bleeding. LVAD therapy may contribute to persistent alterations in the hemostatic system, the impact of which on adverse clinical events remains unclear. The aim of the study was to characterize longitudinal alterations in coagulation in patients supported with continuous-flow LVADs, assessed using the Calibrated Automated Thrombogram (CAT) assay. Basic coagulation parameters were assessed at baseline, 3-4 months, 6-12 months, and every 6 months thereafter. Only patients completing all four scheduled follow-up visits were included in further analyses. Eighty-five patients were recruited; 22 met the inclusion criteria. Significant shift toward a hypocoagulable state was observed: increase in thrombin generation lagtime, decrease in endogenous thrombin potential and peak thrombin concentration (P < 0.001). Markers of persistent fibrinolytic activity were observed. LVAD support was associated with increased albumin and hemoglobin levels, decreased bilirubin, creatinine, and NT-proBNP concentrations (P < 0.05). No significant differences were observed between CAT parameters and adverse events in the investigated group. Long-term LVAD therapy was associated with progressive changes in coagulation parameters, despite a stable anticoagulant and antiplatelet treatment regimen.

