Effects of Cyproheptadine on Mitral Valve Remodeling and Regurgitation After Myocardial Infarction.

Background: Ischemic mitral regurgitation (MR) is primarily caused by left ventricle deformation, but leaflet thickening with fibrotic changes are also observed in the valve. Increased levels of 5-hydroxytryptamine (5-HT; ie, serotonin) are described after myocardial infarction (MI); 5-HT can induce valve fibrosis through the 5-HT type 2B receptor (5-HT2BR).

Objectives: This study aims to test the hypothesis that post-MI treatment with cyproheptadine (5-HT2BR antagonist) can prevent ischemic MR by reducing the effect of serotonin on mitral biology.

Attenuated Mitral Leaflet Enlargement Contributes to Functional Mitral Regurgitation After Myocardial Infarction.

Background: Mitral leaflet enlargement has been identified as an adaptive mechanism to prevent mitral regurgitation in dilated left ventricles (LVs) caused by chronic aortic regurgitation (AR). This enlargement is deficient in patients with functional mitral regurgitation, which remains frequent in the population with ischemic cardiomyopathy. Maladaptive fibrotic changes have been identified in post-myocardial infarction (MI) mitral valves.

Left atrial cross-sectional area is a novel measure of atrial shape associated with cardioembolic strokes.

Objective: Cardioembolic (CE) stroke carries significant morbidity and mortality. Left atrial (LA) size has been associated with CE risk. We hypothesised that differential LA remodelling impacts on pathophysiological mechanism of major CE strokes.

Mechanical effects of MitraClip on leaflet stress and myocardial strain in functional mitral regurgitation - A finite element modeling study.

Purpose: MitraClip is the sole percutaneous device approved for functional mitral regurgitation (MR; FMR) but MR recurs in over one third of patients. As device-induced mechanical effects are a potential cause for MR recurrence, we tested the hypothesis that MitraClip increases leaflet stress and procedure-related strain in sub-valvular left ventricular (LV) myocardium in FMR associated with coronary disease (FMR-CAD).

Methods: Simulations were performed using finite element models of the LV + mitral valve based on MRI of 5 sheep with FMR-CAD.

Mitral Valve Adaptation to Isolated Annular Dilation: Insights Into the Mechanism of Atrial Functional Mitral Regurgitation.

Objectives: This study hypothesized that compensatory mitral leaflet area (MLA) adaptation occurs in patients with persistent atrial fibrillation (AF) without left ventricular (LV) dysfunction but has limitations that augment mitral regurgitation (MR). The study also explored whether asymmetrical annular dilation is matched by relative leaflet enlargement.

Background: Functional MR occurs in patients with AF and isolated annular dilation, but the relationship of MLA adaptation with annular area (AA) is unknown.