P33: Evaluation of the effect of mitral annular calcification on left heart hemodynamics using fluid-structure interaction simulation

Background: Mitral annular calcification (MAC) is a degenerative disease that is associated with cardiovascular comorbidities. MAC leads to severe mitral stenosis and/or mitral insufficiency followed by significant hemodynamic variations within the left atrium (LA) and left ventricle (LV). This study aims to investigate the hemodynamic changes that occur due to MAC using patient-specific Fluid-Structure Interaction (FSI) simulation. Methods: Left atrial (LA), mitral valve (MV), and left ventricular (LV) models of a patient with severely calcified MV were obtained from 4D-CT at mid systole and mid diastole. Patient-specific hemodynamics based on echocardiography data were generated by lumped parameter model with a LA volume change of 25mL and a LV stroke volume of 90mL. The hemodynamics then were applied as boundary conditions for an FSI simulation in which movements of the LA and LV walls were reconstructed from CT scans. Mitral pressure gradients, MV area (MVA), and regurgitant volume were calculated. Results: Calcification of the mitral valve severely restricted the movement of mitral leaflets, resulting in unfavorable hemodynamics within the LA and LV. Impaired mitral leaflets’ mobility leads to 30 mL regurgitant volume into the LA during systole (Figure 1). The mean diastolic mitral pressure gradient was 12.1 mmHg with a MVA of 2.1 cm2 at middiastole and 1.4 cm2 mid-systole with a mean pressure drop for the leakage of 3.5 mmHg (Figure 1). Conclusion: Mitral calcification leads to unfavorable hemodynamics as determined by FSI simulation. Patient-specific simulations are a powerful tool for studying the hemodynamics variations occurring due to MV disease. In the future, it should allow the evaluation of various personalized therapeutic options.