Importance of the subvalvular apparatus in functional mitral regurgitation: insights from in vitro and numerical modeling. (R-4646)

Functional mitral regurgitation (MR) due to abnormal function of structurally normal mitral valve leaflets in the context of heart failure remains a complex and ill-understood pathology, the presence and severity of MR being independently associated with increased morbidity and mortality. The pathophysiology is predominantly related to ventricular dysfunction rather than structural valvular abnormalities, and is based on (1) annular enlargement secondary to ventricular dilatation, and (2) displacement of papillary muscles resulting in tethering of valve leaflets. So far, surgical treatment in patients with severe functional MR has mainly focused on correcting the annular dimensions. However, reports of postoperative recurrence of MR, as well as evidence of functional mitral stenosis induced by surgery, stress the need for targeting the subvalvular pathology as well. Therefore, a better understanding of the interaction between valvular and subvalvular apparatus in patients with functional MR is critically needed. The proposed project aims at (1) developing and validating an original in vitro mitral valve model with externally controllable papillary muscle position, and (2) developing and validating a numerical model of mitral valve ánd subvalvular apparatus, in order to (3) gain fundamental insights in the dynamic pathophysiological interaction between subvalvular apparatus and valve leaflets. Ultimately, these insights may identify possible targets for improvement of treatment.

Keywords:mitral valvular insufficiency, patient safety

Disciplines:Basic sciences, Clinical sciences, Translational sciences