[Structural and functional changes in the heart and 24-hour arterial pressure profile in patients with arterial hypertension in the Far North].

This comparative analysis of structural and functional changes in the heart is based on the results of 24 hour monitoring arterial pressure (MAP) in 393 men aged 20-59 years. Group 1 comprised 220 patients with arterial hypertension (AH) working on a rotating schedule in the Far North. They showed signs of hyper-reactivity of sympathetic component of the vegetative nervous system manifest as the high mean daily heart rate and variability of AP. Significant difference between MAP and office AP values reflected psychoemotional stress reaction during AP measurement. Daily AP rhythm in patients with grade I and II AH was described by a flat AP curve and hemodynamic load at night. The group with grade II AH included a large number of "night peakers" and subjects with inverted daily AP rhythm as a manifestation of external desynchronosis with night-time hypersympathicotonia. Differently directed daily changes of systolic and diastolic AP suggested internal desynchronosis of AP rhythm coupled to a significant increase of left ventricular myocardial mass (LVMM) and LVMM index in the absence of difference between LVDF. Patients with AH showed no correlation between LVMM, LVDF, and MAP values. It is concluded that hyperactivity, desynchronosis, and systemic dysregulation along with hemodynamic loading may play a key role in the development of structural and functional changes in the heart of AH patients during adaptation to extreme conditions of the Far North.

[The rhythms of arterial pressure and heart rate in individuals with arterial hypertension under the conditions of Far North].

The circadian and ultradian rhythms of blood pressure (BP) and heart rate (HR) were studied by means of 24-hour BP monitoring in patients with arterial hypertension (AH) and practically healthy people working in Far North shifts. The subjects were 418 men. The main group consisted of 177 men aged 18 to 59 working in trans-polar shifts in Yamburg, Tyumen region, latitude 57 North. The comparison group included 158 residents of a moderate climatic zone (Tyumen, latitude 57 North). The control group consisted of 83 practically healthy men, of whom 43 worked in Far North shifts, and 40 were residents of Tyumen. The groups were comparable by age, AH duration, and office systolic and diastolic BP (SBP; DBP). The study demonstrates that even healthy people working in Far North shifts display high BP variability and the decrease of the stability and power of SBP, DBP and HR circadian rhythms due to the reduction of the amplitude, contribution of the rhythm to the total variability, and the increase of the amplitude of high-frequency harmonics of the spectrum (a manifestation of extracircadian dissemination), which may be a sign of accelerated ageing and biological age increase, and may facilitate AH development. Development of AH under the extreme conditions of Far North shifts, unlike the conditions of moderate climatic zones, is accompanied by progressive BH variability increase, the worsening of the chronological structure of SBP and DBP, the increase of extracircadian dissemination, which can be of both clinical and prognostic significance.

[24-h profile of arterial pressure in hypertensive patients working in rotatory teams in conditions of Far North (Tyumen Region)].

AIM: To specify a 24-h profile of arterial pressure (AP) in hypertensive patients working in duty regime in the Far North (Tyumen Region). MATERIAL AND METHODS: AP parameters were studied in 155 males aged 25-59 with hypertension of stage I, II who were employed for duty work in the Far North areas and 38 control patients with hypertension stage I, II living in a moderate climatic zone (Tyumen). The groups were comparable by gender, age, duration of hypertension, office systolic and diastolic AP (SAP and DAP). All the patients have undergone 24-h monitoring of AP with assessment of basic mean parameters. RESULTS: The study group patients had scare symptoms and lower mean 24-h SAP, but high AP variability, high DAD as reflection of more significant structural changes of vessels and special functioning of the autonomic nervous system in the North. Mean 24-h AP showed more unfavourable changes in hypertensive subjects who had flight from Yamburg-Moscow-Yamburg. CONCLUSION: The data of the study dictate the necessity to develop a differentiated risk strategy for health promotion, prevention and treatment of hypertension in those who work in the North of Tyumen Region in duty regime.

[Structural changes of the myocardium and 24-hour blood pressure profile in subjects with hypertension studied during expedition work in the Far North].

Echocardiography and 24-hour BP monitoring were carried out in 177 men with stage 1 and 2 essential hypertension aged 25-59 years when they worked the Far North shift (group l) and in 75 patients with essential hypertension living in moderate climatic zone (group 2). Normal left ventricular geometry was found in 10 and 39% of subjects in groups l and 2, respectively. Left ventricular hypertrophy (LVH) was 2 times more frequent in group 1 where it was predominantly concentric. Contrary to group 2 significant correlations between parameters of 24-hour BP monitoring and echocardiography were found in group 1. All variants of left ventricular geometry in group 1 were characterized by lower systolic BP, high variability of systolic and diastolic BP, impaired 24-hour BP rhythm because of decreased night-day difference. Group 1 subjects with concentric left ventricular hypertrophy had significantly increased left ventricular mass index. Diastolic nocturnal hypertension was the factor most closely related to the structural state of the myocardium in group 1.