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arXiv · 2011.10479

Multi-scale simulation of thrombus formation at LVAD inlet cannula connection: Importance of Virchow's triad

R. Mendez Rojano·M. Zhussupbekov·J. F. Antaki
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Abstract

As pump thrombosis is reduced in current-generation ventricular assist devices (VAD), adverse events such as bleeding or stroke remain at unacceptable rates. Thrombosis around the VAD inlet cannula (IC) has been highlighted as a possible source of stroke events. Recent computational fluid dynamics (CFD) studies have attempted to characterize the thrombosis risk of different IC-ventricle configurations. However, purely CFD simulations relate thrombosis risk to ad-hoc criteria based on flow characteristics, with little consideration of biochemical factors. This study investigates the genesis of IC thrombosis including two elements of the Virchow's triad: Endothelial injury and Hypercoagulability. To this end a multi-scale thrombosis simulation that includes platelet activity and coagulation reactions was performed. Our results show significant thrombin formation in stagnation regions (|u|< 0.002 m/s) close to the IC wall. In addition, high shear-mediated platelet activation was observed over the leading-edge tip of the cannula which mirrors the thrombus deposition pattern observed clinically. The current study reveals the importance of biochemical factors to the genesis of thrombosis at the ventricular-cannula junction which can inform clinical decisions in terms of anticoagulation/antiplatelet therapy and guide engineers to develop more robust designs.

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R. Mendez Rojano, M. Zhussupbekov, J. F. Antaki. 2020-11-20. Multi-scale simulation of thrombus formation at LVAD inlet cannula connection: Importance of Virchow's triad. https://arxiv.org/abs/2011.10479

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