Clinical and Morphological Features of Lipomatous Hypertrophy of Interatrial Septum in Patients with Diseases of Cardiovascular System

INTRODUCTION: Epicardial adipose tissue is usually located on the free wall of the right ventricle, the left ventricular apex, and the atria, but the valvular apparatus of the heart, the interventricular and interatrial septum can be subjected to lipotoxic damage. The accumulation of adipose tissue on the interatrial septum is of particular scientific interest and is described in the literature as lipomatous hypertrophy. AIM: To study the clinical and morphological features of lipomatous hypertrophy of interatrial septum in patients with diseases of the cardiovascular system. MATERIALS AND METHODS: Morphological examination of the hearts of 60 patients (30 men, 30 women), average age 74.6 ± 9.5 years was conducted. Morphometric parameters of the heart muscle and the aorta were evaluated. The studied heart material was stained with hematoxylin-eosin and according to Mallory and was processed by standard histological methods. RESULTS: The causes of death of patients were myocardial infarction, cerebral infarction, postinfarction cardiosclerosis and type 2 diabetes. The analysis of thickness of the interatrial septum in patients of different groups revealed lipomatosis of the interatrial septum in 83% of patients with postinfarction cardiosclerosis, in 80% of patients with myocardial infarction, in 70% with type 2 diabetes, in 66.7% with cerebral infarction. The thickness of the interatrial septum with lipomatous hypertrophy was 1.2 ± 0.12 cm in patients with myocardial infarction, 1.2 ± 0.11 cm in cerebral infarction, 1.2 ± 0.2 cm in postinfarction cardiosclerosis, 1.2 ± 0.15 cm in type 2 diabetes. There were no reliable differences in the thickness of the interatrial septum between the study groups. The correlation was established between the thickness of the interatrial septum with lipomatous alterations and hypertrophy of the anterior wall of the left ventricle (r = 0.7; р < 0.0001), fibrosis of the anterior wall of the left ventricle (r = 0.6; p = 0.03), thickness of epicardial fat (r = 0.5; p = 0.0002), as well as the interrelation with the thickness of the interventricular septum (r = 0.7; p < 0.05). The existence of epicardial fat in individuals with lipomatosis of the interatrial septum positively correlated with the thickness of the interventricular septum (r = 0.5; p = 0.01) and the thickness of the posterior wall of the left ventricle (r = 0.6; p = 0.001). The correlation relationship was also established between the thickness of the interatrial septum with lipomatous alterations and laboratory markers of cardiovascular risk: the level of total cholesterol (r = 0.8; p = 0.01), triglycerides (r = 0.6; p = 0.001), low-density lipoproteins (r = 0.7; p = 0.001). CONCLUSION: Taking into account the interrelations of lipomatous hypertrophy of the interatrial septum identified in the morphological and histological examination, as well as echocardiography data and some biochemical markers, this parameter can be recommended for use in assessment of cardiovascular risk in echocardiography.