BIOLOCHANICS

BIOLOCHANICS was a-five year project aimed at achieving patient-specific predictions of aneurysm risk of rupture and of aneurysm reactions to biochemical treatments.

Rupture of Aortic Aneurysms (AA) kills more than 30000 persons every year in Europe and the USA. It is a complex phenomenon that occurs when the wall stress exceeds the local strength of the aorta due to degraded properties of the tissue. The state of the art in AA biomechanics and mechanobiology revealed in 2014 that major scientific challenges still had to be addressed to permit patient-specific computational predictions of AA rupture and enable localized repair of the structure with targeted pharmacologic treatment. A first challenge related to ensuring an objective prediction of localized mechanisms preceding rupture. A second challenge related to modelling the patient-specific evolutions of material properties leading to the localized mechanisms preceding rupture.

We worked at addressing these challenges in BIOLOCHANICS.

We developed digital twin framework for helping clinicians to establish prognosis for patients harbouring an AA. Thanks to Magnetic Resonance Imaging and computer fluid dynamics simulations, we estimate hemodynamics loads on the aortic wall. The impact of the hemodynamics loads on the mechanical properties aortic tissue and aortic smooth muscle cells has been extensively characterized throughout the project. Eventually we simulate the induced evolutions through finite element models to predict aneurysmal progression and potential risk of rupture.

A first group of patients is currently evaluating this digital twin framework which has been summarized with the following schema.

The Biolochanics project has led to the publication of 45 publications in international journals, 1 patent. Numerous students and postdocs have worked in this project and major international collaborations have been initiated.

The following 5 journal papers give a nice overview of our scientific achievements:

1. Biaxial rupture properties of ascending thoracic aortic aneurysms. Acta Biomaterialia, 2016,

2. Multimodality imaging-Based characterization of Regional Material properties in a Murine Model of Aortic Dissection. Scientific Reports, 2020.

3. Relationship between ascending thoracic aortic aneurysms hemodynamics and biomechanical properties, IEEE Transactions on Biomedical Engineering, 2019

4. Regulation of SMC traction forces in human aortic thoracic aneurysms. Biomechanics and Modeling in Mechanobiology, 2021.

5. Coupling hemodynamics with mechanobiology in patient-specific computational models of ascending thoracic aortic aneurysms. Computer Methods and Programs in Biomedicine, 2021, 205, 106107.