Power spectrum analysis of heart rate and blood flow velocity variability measured in the umbilical and uterine arteries in early pregnancy: a comparative study

Abstract

Objective To compare power spectral derived variability parameters from the fetal side of the placental circulation with those from the maternal side of the placental circulation, during early pregnancy. Methods

Spectral Doppler And Resistive Index. A promising tool in ultrasonographic evaluation of inflammation in rheumatoid arthritis

“…The RI has been used in obstetrics and in nephrology to give a numerical value for the diastolic component in the umbilical arteries and arteries of the transplanted kidney (21, 23). In these two parts of the body, the arteries supply a low resistance arterial bed where flow must be present throughout the cardiac cycle.…”

Approximate entropy of fetal heart rate variability as a predictor of fetal distress in women at term pregnancy

“…Sympathetic and parasympathetic control of FHR variability via the sinoatrial node results in moment-to-moment or beat-to-beat oscillation of the FHR (1,2,5). Such regulation normally varies with fetal behavioral state (2), reninangiotensin system (6)(7)(8), and gestational age (9,10). Of clinical interest, FHR variability has been considered as a useful measurement for fetal health in either antepartum or intrapartum, and the decrease or disappearance of FHR variability has been linked to fetal distress (11,12).…”

Application of the Magnitude-Squared Coherence Function Between Uterine and Umbilical Flow Velocity Waveforms for Predicting Placental Dysfunction: A Preliminary Study

“…Such similarities included a peak at the maternal respiration frequency in both spectra (Struijk et al 2001). This study suggested that intervillous pressure fluctuations might induce umbilical flow velocity variability.…”