The effect of impedance cardiography directed antihypertensive therapy on fetal growth restriction rates and perinatal mortality in women with chronic hypertension.

Objectives: We sought to determine the effect of impedance cardiography directed medical antihypertensive therapy on fetal growth restriction and perinatal mortality in women with chronic hypertension.

Study Design: A retrospective study was conducted on 958 women referred to the Maternal Hypertension Center at Cabell Huntington Hospital between 2005 and 2014 for the indication of chronic hypertension.

Main Outcome Measures: Serial assessments of maternal hemodynamics were obtained using non-invasive impedance cardiography. Vasodilators were initiated for increased systemic vascular resistance. Elevated cardiac output was treated with beta blockade.

Results: Blood pressure at initial visit was used to stratify patients into five groups. Initial blood pressure of <130 systolic or <80 diastolic had 24 cases of growth restriction (6.8%) and 6 perinatal deaths (1.7%), 130-139 systolic or 80-89 diastolic resulted in 29 cases of growth restriction (9.3%) and 9 perinatal deaths (2.9%), 140-149 systolic or 90-99 diastolic 14 cases of growth restriction (6.5%) and 3 perinatal deaths (1.4%), 150-159 systolic or 100-109 diastolic had 5 cases of growth restriction (8.6%) and 4 perinatal deaths (6.89%), and >160 systolic or >110 diastolic 3 cases of growth restriction (13%) with no perinatal deaths. There were no differences in growth restriction (p = .59) or perinatal death (p = .15) between the groups.

Conclusion: The rates of IUGR and perinatal mortality did not increase even with increasing severity of maternal hypertension. This low cost and non-invasive test should be considered for optimizing rates of growth restriction and perinatal mortality in pregnancies complicated by chronic hypertension.