A METHOD FOR DEVELOPING MRI-BASED FINITE ELEMENT MODELS OF THE LEFT VENTRICLE WITH MITRAL VALVE AND CHORDAE TENDINEAE

摘要

Ischemic mitral regurgitation (MR) affects 1.2 to 2.1 million patients in the United States, with more than 400,000 patients having moderate-to-severe MR [1]. As a consequence of left ventricular remodeling after postero-basal myocardial infarction (MI), the posterior papillary muscle moves laterally. This causes both anterior and posterior mitral leaflets to be tethered, and type 3B Carpentier leaflet motion (restricted motion during systole) and ischemic MR to occur. Finite element (FE) modeling of the heart and heart valves is becoming more common and is an extremely useful predictive tool. However, many of these studies only examine the left ventricle or mitral valve as isolated structures [2,3]. In the current study, we expand our previous FE models of the left ventricle (LV) [4] to incorporate the leaflets and chordae of the mitral valve. The model is based on magnetic resonance imaging (MRI) data from a sheep that developed moderate ischemic MR after postero-basal MI. We demonstrate the utility and power of the method by using the FE model to investigate the effects of modifying contractility (T_(max)) in the borderzone around the infarcted region on the displacement of the posterior papillary muscle and leaflet coaptation.