24-hour ECG frequency-domain measures in preeclamptic and healthy pregnant women during and after pregnancy.

OBJECTIVE: The aim of the present study was to evaluate the autonomic balance in women with preeclampsia and in healthy women during and after pregnancy by means of a 24-h ECG Holter recording combined with power spectral analysis. METHODS: Fifteen preeclamptic and 15 healthy women underwent 24-h Holter monitoring in the 32nd-36th week of gestation and 3-6 months postpartum. The power spectrum of the maternal electrocardiogram was analyzed with an autoregressive algorithm. MAIN OUTCOME MEASURES: The power spectrum contains two major components: a low-frequency peak, primarily attributed to sympathetic tone, and a high-frequency peak, reflecting vagal tone. RESULTS: The power spectrum of maternal heart rate variability did not differ between preeclamptic and normal women during pregnancy. After delivery, the amplitude of all components became significantly higher than those during pregnancy, with one exception: the high-frequency component in the patients who had been preeclamptic. In a comparison of the two groups, the high-frequency component after delivery was significantly lower in women who had preeclampsia than in normal healthy women (p = 0.03). CONCLUSIONS: During pregnancy, the power spectrum is reduced and cannot be used to distinguish between patients with preeclampsia and normal healthy women. Three to 6 months after delivery, the high-frequency component is still reduced in the preeclamptic group of women. This indicates an impaired vagal modulation even in the nonpregnant state in this group of women, unlike those who had a normotensive pregnancy.

Increased serum concentrations of interleukin-2 receptor in the first trimester in women who later developed severe preeclampsia.

BACKGROUND: To determine the concentration of cytokines having an immunomodulating effect in the first trimester in women who subsequently developed preeclampsia. METHODS: The serum concentrations of IL-10, TNFalpha, IL-6 and IL-2R were determined in ten women who later developed severe preeclampsia and in ten healthy controls. The groups were compared with the Mann-Whitney U test. RESULTS: The IL-2R concentration was significantly higher in the women who later developed preeclampsia than in normal patients (p = 0.028). No significant differences were detected between the groups with respect to the other evaluated cytokines. CONCLUSION: Elevated IL-2R concentrations in maternal serum as early as in the first trimester may be a sign of immunological maladaptation and might be associated with a disturbance of trophoblastic invasion.

Preeclampsia and maternal heart rate variability.

Maternal heart rate variability was evaluated by means of 24-hour Holter ECG monitoring in three groups of patients (15 preeclamptic, 15 women hospitalized due to other complications and 15 normal ambulatory pregnant women) in the 28th-33rd week of gestation. Heart rate variability was estimated by time and frequency domain measures. Patients with preeclampsia had significantly longer NN intervals during daytime compared to the other groups studied. With regard to frequency domain measures such as very-low-frequency, low-frequency and high-frequency power, the groups did not differ. Nor did they differ with regard to day and nighttime. We conclude that during pregnancy, the power of the maternal heart rate spectrum is markedly depressed, which affects the power of the method to separate normal pregnancies from pregnancies affected by preeclampsia.