Oxidative stress and cardiac dysfunction in children with chronic cardiac failure

Abstract

Introduction. Currently, chronic heart failure (CHF), a polyetiological syndrome, is defined as a dynamic process in which neuroendocrine changes and hemodynamic factors contribute, causing myocardial remodeling and alteration of its functionality, metabolic changes and other disorders. The prevalence of chronic heart failure is increasing worldwide, having a poor prognosis and reducing the prospect of survival, altering the quality of life, producing disability and being associated with increased morbidity. Chronic myocardial dysfunction (CMD) represents the final event in the evolution of any cardiovascular disease and maintains cardiovascular morbidity at a constant high level. Obviously, the progressive incidence and complexity of the clinical picture of heart failure syndrome place its study at the forefront of contemporary medicine. Objective: The objective of this study was to evaluate cardiac function in children with cardiac disease using echocardiography and correlate results with plasma hidroperoxid level and total antioxidant activity as a marker of oxidative stress. Material and Methods: The study involved 104 children with chronic cardiac failure and hypertension, divided into two groups and 52 healthy controls. The plasma lipid hydroperoxides levels were measured, and cardiac function was evaluated using conventional echocardiography. Echocardiography – with assessment of all hemodynamic parameters, including the diameters of the heart chambers, intracavitary volumes (VTDVS, VTSVS), and IMMVS, IMMVS, signs of LV myocardial hypertrophy, LV wall thickness. automated ambulatory monitoring of blood pressure (BP/24 hours) with assessment of the diurnal and nocturnal BP profile. The primary materials of the study were processed computerized using the "Statistical Package for the Social Science" program using methods of variational, descriptive analysis. To estimate the significant differences in the means of two groups, the Student criterion was used. Testing the dynamics of group parameters was carried out through the T test, a coherent selection criterion. To estimate the significant differences in the values of the weights of the positive samples of two groups, the U-Fischer criterion was used. Rezults. The values of cardiac performance parameters (MMVS, IMMVS) showed significant increases in both groups compared to the control group both at the study inclusion stage and at 6 months of observation (p<0.001). Thus, MMVS initially increased in group I by 103%, and in group II by 128%, after 6 months it remained increased in group I by 91%, and in group II – by 108% respectively. The changes in LV myocardial mass index in both groups were distributed so that initially IMMVS in both groups was increased by 78% in comparison to the control group, and after 6 months the values presented changes expressed for group I by 86%, and for group II – by 91%. According to the data obtained, the increase in the intensity of lipid peroxidation, concomitant with the inhibition of total antioxidant activity, was found upon admission, where early lipid hydroperoxides increased in group I by 38%, and in group II by 43%, while AAT in the first group decreased by 17,1%, and in group II by 20% compared to the control group. Conclusion: Significant oxidative stress was present in children with chronic cardiac failure and was correlated with the degree of cardiac dysfunction detected early using the cardiac imaging M-mode and twodimensional (2D) echocardiography and Doppler modality. The severity of chronic heart failure in the objective clinical examination is difficult to assess and, in this regard, the key examination is EchoCG.