Assessment of Myocardial Diastolic Dysfunction as a Result of Myocardial Infarction and Extracellular Matrix Regulation Disorders in the Context of Mesenchymal Stem Cell Therapy.

The decline in cardiac contractility due to damage or loss of cardiomyocytes is intensified by changes in the extracellular matrix leading to heart remodeling. An excessive matrix response in the ischemic cardiomyopathy may contribute to the elevated fibrotic compartment and diastolic dysfunction. Fibroproliferation is a defense response aimed at quickly closing the damaged area and maintaining tissue integrity. Balance in this process is of paramount importance, as the reduced post-infarction response causes scar thinning and more pronounced left ventricular remodeling, while excessive fibrosis leads to impairment of heart function. Under normal conditions, migration of progenitor cells to the lesion site occurs. These cells have the potential to differentiate into myocytes in vitro, but the changed micro-environment in the heart after infarction does not allow such differentiation. Stem cell transplantation affects the extracellular matrix remodeling and thus may facilitate the improvement of left ventricular function. Studies show that mesenchymal stem cell therapy after infarct reduces fibrosis. However, the authors did not specify whether they meant the reduction of scarring as a result of regeneration or changes in the matrix. Research is also necessary to rule out long-term negative effects of post-acute infarct stem cell therapy.