Indicators of ambulatory blood pressure monitoring in patients with essential hypertension of the 2-nd stage depending on the type of 24-hours blood pressure profile, the state of the left ventricular diastolic filling and endothelial function of vessels

Annotation. Arterial hypertension (AH) is one of the most important risk factors for the development of cardiovascular complications and mortality in the world and it has become a medical and social problem. The prevalence of hypertension will increase to 1.56 billion by 2025, making the disease a very serious problem. The severity of clinical manifestations and prognosis in patients with hypertension are determined not only by the degree of increase in blood pressure (BP) but also the damage to target organs. The load on the cardiovascular system caused by elevated BP leads to structural remodelling of the heart and vessels. The aim – to evaluate peculiarities of indicators of ambulatory blood pressure monitoring in patients with essential hypertension of the 2nd stage depending on the type of 24-hours blood pressure profile, the state of the left ventricular diastolic filling and endothelial function of the vessels and determine independent clinical and instrumental criteria of the 24-hours profile “dipper” and “non-dipper”. The study involved 110 patients (40 men and 70 women) with hypertension of the II-nd stage, hypertensive heart, chronic heart failure of the 0-I stage (average age was 54.19±0.89 years). The patients underwent 24-hour blood pressure monitoring, echocardiography and determination the thickness of the intima-media complex (IMCT) of the brachial artery, endothelium-dependent (EDVD) and endothelium-independent (EIVD) vasodilatation. For statistical analysis, arithmetic means (M), errors of mean values (m), t - Student's t test for paired measurements were calculated. Correlation ratios were evaluated by the method of linear correlation for parametric data and the method of Spearman’s rank correlation for nonparametric data. Paired group comparisons were performed by the nonparametric Mann-Whitney method. Wilcoxon test was used in the analysis of dependent samples. Step-by-step multifactor regression was used to identify independent criteria for daily blood pressure profiles. Two types of 24-hours profile of blood pressure – “dipper” and “non-dipper” were detected. The left ventricle diastolic dysfunction (LVDD) by type of relaxation disorder was observed in all “non-dipper” patients and most “dipper” patients. Patients with DD had higher levels of BP per 24-hours, day, night, corresponding the time indexes, the magnitude of the morning increase of systolic and diastolic blood pressure, more pronounced structural changes of the heart and vessels compared with patients with preserved diastolic filling of the LV(р<0,01). The duration of the hypertensive anamnesis (p=0.0002), the thickness of the posterior wall of the LV (p=0.002), the maximum speed of early diastolic filling of the LV (E) (p<0.0001), the LV ejection fraction (p=0.001), the index of the left atrium (p=0.008), the thickness of the intima-media complex of the brachial artery (p=0.013), increase of the diameter of the brachial artery in 90 s after compression (EDVD) (p<0.0001) and in 5 min after taking of nitroglycerin (EIVD) (p=0.009) were determined as independent clinical and instrumental criteria of the “dipper” and “non-dipper” profile. Insufficient the degree of the nightly decrease of the BP, higher magnitude of the morning increase of systolic and diastolic BP cause more hemodynamic pressure on target organs and lead to more significant pathological remodeling of the LV and vessels, disorders of the LV relaxation processes and endothelial dysfunction.