With 600 surgical operations per year, mitral insufficiency is the second cause of valvular surgery in France. Repair is preferred to replacement when it is possible. Cardiac ultrasound allows the quality of correction to be routinely assessed, but it does not measure the biomechanical impact of interventions on the mitral apparatus. A better understanding of this impact, based on objective physical quantities, would enable the optimization of the repair techniques.
The SIMR project aims at facing this major public health problem, with the following two objectives:
(1) Evaluate the physical consequences of mitral repair with new tools used in a clinical study involving 15 patients. Tissue remodeling and ventricular flow will be measured using advanced magnetic resonance imaging techniques, and chordae tension will be measured using an innovative device.
(2) Design numerical tools for the simulation of cardiac hemodynamics, blood/valve interaction and myocardial biomechanics, to provide the in silico counterpart of the in vivo measurements. In particular, a new fluid-structure coupling algorithm will be developed to allow a complete numerical simulation of the mitral apparatus, and inverse problem techniques applied to a finite element model will be used to estimate cardiac contractility.
The SIMR consortium gathers four complementary components: modeling and simulation (REO, M3DISIM, TIMC), clinical research (HCL), engineering (LGEF) and medical imaging (CREATIS). Active collaborations already exist between certain groups. The project will provide a unique opportunity to build new bridges between imaging, modeling, simulation and clinical research.
Several results with high scientific impact are expected. The device for measuring tensions in neo-cordages is a world first. At the end of the project, the impact of these tensions on the results of the repair and ventricular remodeling will be much better understood. The combination of magnetic resonance imaging velocimetry and numerical simulation is likely to be of great interest as intracavitary flows are currently a very active research field within in the imaging and simulation communities. Finally, a complete fluid-structure simulation of the mitral apparatus on a beating heart would be a major breakthrough in the field of cardiovascular simulation.
Monsieur Miguel A. Fernández Varela (Centre de Recherche Inria de Paris)
The author of this summary is the project coordinator, who is responsible for the content of this summary. The ANR declines any responsibility as for its contents.
CREATIS - CNRS CENTRE DE RECHERCHE EN ACQUISITION ET TRAITEMENT D'IMAGES POUR LA SANTE
HCL CIC LYON
LGEF LABORATOIRE DE GENIE ELECTRIQUE ET FERROELECTRICITE
TIMC Techniques de l'Ingénierie Médicale et de la Complexité - Informatique, Mathématiques et Applications, Grenoble
COMMEDIA Centre de Recherche Inria de Paris
M3DISIM Centre de Recherche Inria Saclay - Île-de-France
Help of the ANR 733,903 euros
Beginning and duration of the scientific project: January 2020 - 48 Months