Relationship between glomerular and tubularile kidney injuries and clinical course, morpho-functional parameters of the heart and hemodynamic indicators in patients with coronary heart disease, postinfarction cardiosclerosis and arterial hypertension

Objective: to study the characteristics of cardiorenal relationships in patients with coronary heart disease (CHD) who have suffered a myocardial infarction in combination with CKD. Materilas and methods: the study included 110 patients with coronary heart disease who had suffered acute myocardial infarction (AMI) in combination with grade 1–2 hypertension, who also had CKD stages 1-3. The clinical study included clarification of the functional class of CHF using a 6-minute walk test (TSH), assessment of the severity of CHF on the SHOKS scale, electrocardiography (ECG), echocardiography (ECHOCG), daily blood pressure monitoring (SMAD), Holter ECG monitoring. The functional state of the kidneys was assessed by the level of glomerular filtration rate (GFR) (formula CKD-EPI), the ratio of albumin to creatinine in daily urine (AU), as well as by the level of N-acetyl-β-D-glucosaminidase (NAG) in urine. Results: exceeding the level of reference NAG values in urine demonstrated a close association with damage to the epithelium of the proximal tubules. In the studied group, the number of patients with a NAG level of more than 3.16 ng/ml was 96 patients (87.3%). It was shown that the levels of NAG and AU are closely related (r = 0.86, p = 0.001). When analyzing the values of TSH, it was found that as the value of TSH decreased, the level of AU increased (r = 0.34, p < 0.05). It was shown that an increase in the SHOCK score was associated with a decrease in GFR (r = -0.44, p < 0.05). There was no significant correlation between this parameter and AU and NAG in urine. As the left heart dilates, as well as systolic function decreases and myocardial hypertrophy progresses, there is a statistically significant decrease in GFR. It was shown that the values of NAG in urine and AU were higher in a subgroup of patients with concentric hypertrophy. During the analysis of the interrelationships of SMAD indicators and parameters reflecting damage to renal tissue, an increase in the average daily SAD was noted with an increase in the level of NAG in urine and a decrease in GFR. An increase in the level of NAG in urine is also associated with an increase in the variability of SAD, an increase in the index of hypertension time and the rate of morning blood pressure rise. Changes in the values of GFR and AU have fewer connections with the parameters of the SMAD. When analyzing the results of Holter ECG monitoring, it was found that as GFR decreases, the probability of detecting cases of myocardial ischemia (SIM) increases, as well as the duration of all episodes of myocardial ischemia. An increase in the concentration of NAG in urine is associated with an increase in the likelihood of SIM, as well as the duration of episodes of pain-free myocardial ischemia (BBIM). Conclusions: tubular lesions in the form of an increase in the level of NAG in urine, glomerular lesions in the form of AU and a decrease in the filtration capacity of the kidneys (decrease in GFR) in CKD are associated with the processes of myocardial remodeling in patients with coronary heart disease, PIC and hypertension equally, however, high variability of hypertension, pathological daily profiles of hypertension are more associated with the presence of tubular lesions At the same time , the occurrence of episodes of myocardial ischemia and the duration of pain–free ischemia are associated with the presence of glomerular and tubular lesions.