סמינר מחלקה לי גלילי - מודל ביומכני חישובי של טיפול באי ספיקת המסתם המיטרלי על ידי תיקון עקיף של הטבעת.
CHOOL OF MECHANICAL ENGINEERING SEMINAR
Wednesday, June 16 2021 at 14.00
Numerical Biomechanics Modeling of Indirect Mitral Annuloplasty Treatments for Functional Mitral Regurgitation
M.Sc. student of Gil Marom
Mitral valve regurgitation (MR) is a common valvular heart disease with limited available treatments. In this disease, an improper closure of the valve leads to a leakage from the left ventricle into the left atrium. The current study focuses on functional MR which is usually caused by left ventricular dysfunction and has an estimated incidence of two million people worldwide. Although the standard treatment for sever functional MR is an open-heart surgery, it is prohibited for large population of inoperable patients. Therefore, there is a need for alternative treatments, such as percutaneous repairs based on delivery by catheterization. The aim of this study is to examine two types of indirect mitral annuloplasty (IMA) percutaneous repair techniques by finite element analyses. The two types of generic IMA devices that were considered are based on coronary sinus vein shortening (IMA-CS) to reduce the annulus perimeter and shortening of the anterior-posterior diameter (IMA-AP) by connecting the coronary sinus and the left ventricle. The disease, its treatments, and the heart function post-repair were modeled by modifying the living heart human model (LHHM; Simulia, Dassault Systèmes), an electro-mechanically coupled simulator of the entire heart. First, the functional MR pathology was generated in the LHHM. The material properties in regions of the posterior papillary muscles were changed from being active to passive, so they were prevented from contracting, thus representing ischemic MR because of myocardial infraction. Then, this MR pathology was used to determine the effect of the disease on the valve closure and to quantify the leakage. The IMA treatments were simulated in the pathologic MR, following by heart function simulations with the implanted device and leakage quantification simulation. The results demonstrated that all treatments were able to reduce the leakage and that IMA-AP device was able to completely seal the valve. Therefore, it is recommended to treat functional MR by IMA-AP device and shorter implantation leads to better outcomes. The results of this study can help in bringing IMA-AP to market, expand the use of IMA devices in general, and help optimizing future designs of such devices.