Arterial stiffness in preeclamptic and chronic hypertensive pregnancies.

Objective: To assess arterial stiffness in pregnancies complicated by hypertensive disorders: preeclampsia and chronic hypertension.

Study Design: Twenty preeclamptic and 18 chronic hypertensive parturients were studied. The reference data were obtained from 29 healthy pregnant women and 29 non-pregnant women. Systolic blood pressure (SAP), diastolic blood pressure (DAP), mean arterial pressure (MAP) and pulse pressure (PP) were measured. Stroke index (SI), heart rate (HR), cardiac index (CI), systemic vascular resistance index (SVRI) and pulse wave velocity (PWV) were derived by whole-body impedance cardiography. Arterial compliance was defined as the SI to PP ratio (SI/PP).

Results: Significantly higher PP and PWV and lower SI/PP were observed in preeclamptic compared to uncomplicated pregnancies. Preeclamptic pregnancies also differed from chronic hypertensive pregnancies by higher PP and lower SI/PP. Women with chronic hypertension had significantly higher PWV than the control group, but PP and SI/PP were not different. In both hypertensive groups SVRI was exceptionally high.

Conclusions: Besides the vasoconstriction of smaller peripheral arteries, our finding of increased arterial stiffness in preeclamptic pregnancies suggests that also larger arteries with altered viscoelastic properties are involved in the aberrant hemodynamics of preeclampsia. Compared to preeclamptic subjects, women with chronic hypertension shared a common feature of high systemic vascular resistance, but changes in arterial stiffness were less than in preeclampsia.