Loss of Myofibrils in Cardiomyocytes as a Morphological Indicator of Reduced Compensatory Capabilities of Hypertrophied Myocardium.

The functioning of the ventricular myocardium in hypertrophic cardiomyopathy (HCM) under high hemodynamic load leads to depletion of its resources and is associated with the risk of developing a dilated stage. In patients with HCM, the cardiomyocytes of the interventricular septum are hypertrophied, the proportion of cardiomyocytes in which myofibrils constitute less than 50% of the sarcoplasm volume increases with increasing the cardiomyocyte length and correlates with echocardiographic signs of left ventricular obstruction. These cardiomyocytes are characterized by ultrastructural signs of synthetic activity.

[Morphology of the myocardium of the interventricular septum in children with hypertrophic cardiomyopathy].

Objective: To carry out a comparative analysis of the morphology of the interventricular septum (IVS) myocardium in children with hypertrophic cardiomyopathy (HCM) and without cardiovascular pathology.

Material And Methods: A study of myocardial biopsies of the IVS in children with HCM (=18, 1.2-17 years) and children without cardiovascular pathology (=11, 1-16 years) was carried out.

Morphological Features of the Ascending Aorta Remodeling and Activation of Regeneratory Potential in Intima when Forming Aneurysm.

In patients with an ascending aorta aneurysm, restructuring of all its layers and, first of all, the intima and media was revealed. The thickness of the intima was 79.3±63.

Accelerated Growth, Differentiation, and Ploidy with Reduced Proliferation of Right Ventricular Cardiomyocytes in Children with Congenital Heart Defect Tetralogy of Fallot.

The myocardium of children with tetralogy of Fallot (TF) undergoes hemodynamic overload and hypoxemia immediately after birth. Comparative analysis of changes in the ploidy and morphology of the right ventricular cardiomyocytes in children with TF in the first years of life demonstrated their significant increase compared with the control group. In children with TF, there was a predominantly diffuse distribution of Connexin43-containing gap junctions over the cardiomyocytes sarcolemma, which redistributed into the intercalated discs as cardiomyocytes differentiation increased.

Morpho-functional changes of cardiac telocytes in isolated atrial amyloidosis in patients with atrial fibrillation.

Telocytes are interstitial cells with long, thin processes by which they contact each other and form a network in the interstitium. Myocardial remodeling of adult patients with different forms of atrial fibrillation (AF) occurs with an increase in fibrosis, age-related isolated atrial amyloidosis (IAA), cardiomyocyte hypertrophy and myolysis. This study aimed to determine the ultrastructural and immunohistochemical features of cardiac telocytes in patients with AF and AF + IAA.