Do heart rate and velocity variability derived from umbilical artery velocity waveforms change prior to clinical pregnancy‐induced hypertension?

Abstract

Objective To investigate the hypothesis that alterations in heart rate variability, peak systolic velocity variability and time-averaged velocity variability in the human umbilical artery may predict early signs of dysfunctional fetalplacental coupling in pregnancies that later develop pregnancy-induced hypertension.Methods Doppler flow velocity recordings from the umbilical artery were performed at 10-20 weeks of gestation in 12 nulliparous women who subsequently developed pregnancy-induced hypertension. From umbilical artery velocity waveforms of at least 12 s in duration we determined absolute values and beat-to-beat variability in fetal heart rate, peak systolic and time-averaged velocity and compared these findings with those in normal nulliparous pregnant women matched for gestational age.Results Absolute values for fetal heart rate, peak systolic and time-averaged velocity as well as beat-to-beat variability in fetal heart rate did not differ significantly between women later developing pregnancy-induced hypertension and normal controls. However, variability in peak systolic velocity and time-averaged velocity were decreased in women who subsequently developed pregnancy-induced hypertension.Conclusions Whereas fetal heart rate variability was similar, umbilical artery flow velocity variability was reduced in women developing pregnancy-induced hypertension compared with controls. It is proposed from this study that variability of the umbilical artery flow velocity is associated with mechanical changes in the vascular bed of women who later develop pregnancy-induced hypertension.

Arginine vasopressin infusion is sufficient to model clinical features of preeclampsia in mice

“…In addition to uterine artery dysfunction, defects in umbilical artery flow have also been associated with adverse pregnancy outcomes (28)(29)(30)(31). Specifically, multiple groups have demonstrated associations between decreased umbilical PSV and PE (32,33), with others demonstrating associations between decreased, absent, or even reversed diastolic umbilical velocity and increased RI with uteroplacental insufficiency seen in PE (34,35). In pregnant mice receiving AVP infusion, umbilical artery PSV ( Figure 2E) was decreased and EDV ( Figure 2F) and RI ( Figure 2G) were unchanged.…”

Fetal heart rate and umbilical artery flow velocity variability in intrauterine growth restriction: a matched controlled study

“…This approach allowed us to establish flow velocity variability and heart rate variability patterns from umbilical artery waveform recordings lasting at least 18 s, reflecting hemodynamic regulation in the developing fetus. In pregnancies complicated by pregnancy‐induced hypertension or insulin‐dependent diabetes mellitus, significant changes in umbilical artery flow velocity variability and heart rate variability were found11, 12. Heart rate variability is influenced by the autonomic nervous system and increases with advancing gestational age as the parasympathetic system matures13.…”

Fetal heart rate and umbilical artery velocity variability in fetuses with congenital cardiac defects: a preliminary study

“…We recently established that the pregnancy period of 10-20 weeks is characterized by gestational age-related changes in both fetal heart rate variability and umbilical artery peak systolic velocity variability 4 . In pregnancies complicated by pregnancy-induced hypertension or insulin-dependent diabetes mellitus, we noted altered fetal heart rate variability and umbilical artery velocity variability compared with normal pregnancies, suggesting impaired fetal cardiovascular homeostasis 5,6 . Heart rate variability and umbilical artery velocity variability can be indicative of physiologic and pathophysiologic hemodynamic processes.…”