[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.