Hemodynamic Allostasis of Pregnant Women against the Background of Preeclampsia

We analyzed diurnal hemodynamic parameters (HR, systolic BP, and diastolic BP) recorded from two groups of edematous and preeclamptic pregnant women. The unidirectional character of changes in the control over the functional state of cardiovascular system was revealed except for the indices, which mark a pathological process: elevated diurnal BP in preeclampsia and diminished percentage of oscillation power in edematous patients. Uniformity of the regulatory changes in patients with and without arterial hypertension can be viewed as manifestation of allostasis developed by the cardiovascular system during pregnancy. In preeclampsia, the greater allostatic load was reflected by the changes in diurnal, daytime, and nighttime BP and in the circadian index calculated for HR, systolic BP, and diastolic BP. In edematous patients, elevation of allostatic load was indicated by the percentage of ultradian rhythms.