126. Venous modelling to inform the treatment of patients with deep vein thrombosis of the lower limb

Abstract

Deep vein thrombosis (DVT) of the lower limb is a condition in which blood clots form in deep veins due to pathological changes in blood vessels. DVT and associated pulmonary embolism affect 1-2 per 1,000 people each year [1]. Up to 30% will die within few months and 20-50% will develop long-term complications, such as post-thrombotic syndrome, PTS [2]. 

Current clinical workflow of DVT and PTS handling is based primarily on the interpretation of images (MRV, CTV, IVUS). Evidence-based clinical decision making requires more research [3]. Variable symptoms of DVT/PTS and complex anatomy may need a personalised approach. Understanding the influence of thrombosis on blood flow could provide information unavailable in the clinic. Numerous studies describe fluid dynamics of the arterial circulation, but few report work on veins – a notable mention is one by Muller and Toro [4]. 

In this research, a zero-D model was developed to characterise system-scale blood circulation below the abdomen. Extensive sensitivity analysis assessed the influence of variation in anatomy on haemodynamics of the network – a key step towards model personalisation. A set of idealised 3D geometries of veins prone to thrombosis allowed to investigate the influence of geometric parameters and boundary conditions on e.g., wall shear stress (WSS) distribution. Ongoing work focuses on understanding the necessary feature resolution in patient-specific geometries. 

The goal is to find a link between patient-specific venous anatomy in DVT and haemodynamic parameters related to thrombosis (e.g. WSS) and assess their importance in the clinic. 

Model development is informed by direct collaboration with Mr Chung Lim at the Royal Free London NHS Foundation Trust Hospitals and the computational workflow is designed to be positioned within the clinical workflow, with work ongoing to personalise both 0D and 3D models using clinical imaging data.

[1] M. Beckman et al., “Venous thromboembolism: a public health concern.”, American Journal of Preventive Medicine 38, S495–S501 (2010)

[2] M. J. Baldwin et al., “Post-thrombotic syndrome: a clinical review”, Journal of Thrombosis and Haemostasis 11, 795–805 (2013)

[3] S. Kahn, “The post-thrombotic syndrome”, Hematology. American Society of Hema-
tology. Education Program 1, 413–418 (2016)

[4] L. Müller and E. Toro, “A global multiscale mathematical model for the human cir-
culation with emphasis on the venous system”, International Journal for Numerical
Methods in Biomedical Engineering 30, 681–725 (2014).

About the author

Magdalena Otta holds a Master of Physics (Hons) degree obtained at the University of Edinburgh in 2021. The subject of her thesis was modelling a single-cell response to fractionated radiotherapy to induce the abscopal effect in cancer treatment. She joined Sano in September 2021 and is currently working in the modelling and simulation domain as a member of the Extreme Scale Data and Computing team. At the same time, she started a PhD degree at the University of Sheffield (School of Medicine and Population Health) where she works on mathematical modelling in medicine. The subject of her thesis is venous modelling to inform the treatment of patients with deep vein thrombosis of the lower limb.