Alterations in ductus venosus velocity indices in relation to umbilical venous pulsations and perinatal outcome

Abstract

Introduction. Abnormal blood velocity in the ductus venosus is more frequently detected than pulsations in the umbilical vein, but both are considered to be indicators of fetal compromise. The aim of this study was to investigate blood flow patterns in the ductus venosus and the association between individual blood velocity ratios and pulsations in the umbilical vein and perinatal outcome. Material and methods. Retrospective cohort study on Doppler ultrasound examination of ductus venosus and umbilical venous blood velocity in 358 high-risk pregnancies. Ductus venosus blood velocity pattern was analyzed for pulsatility index and the following velocity ratios: S/ ES, S/a and ES/a (where S is systole, ES is end-systole, and a is atrial contraction). Ductus venosus ratio z-scores were calculated and related to pulsations in the umbilical vein and adverse perinatal outcome. Results. Systolic ratios in the ductus venosus were less frequently abnormal than ratios taking into account diastolic velocities, particularly at full-term. High S/ES, ES/a ratios and pulsatility index (z-score >2), were all related to presence of pulsations in the umbilical vein. Umbilical venous pulsations were the best indicator of adverse perinatal outcome. Conclusions. Changes in ductus venosus blood flow during systole occur more rarely than diastolic changes, and alterations in end-diastolic blood velocity in the ductus venosus might give falsepositive indications of worsening fetal condition. Umbilical venous pulsations seem to better predict adverse outcome of pregnancy than do indices in the ductus venosus.

Ductus venosus Doppler waveform pattern in fetuses with early growth restriction

“…Moreover, overt myocardial dysfunction is not universally present in all cases of FGR with elevated DV‐PIV . Other authors have already suggested that velocity ratios of the individual phases of the DV waveform might show relationships with cardiac function that are not detected by the DV‐PIV and that might predict adverse outcome in high‐risk pregnancies . In keeping with these findings we hypothesized that a decrease of the forward flow during isovolumetric ventricular relaxation, as demonstrated by a reduced maximum forward velocity of the v‐wave, might be associated with worsening myocardial hypoxia and adverse perinatal outcome.…”

“…Picconi et al reported an increased risk of fetal demise in FGR fetuses with deep v‐waves and developed a DV Doppler index incorporating a direct measurement of the v‐wave that, when compared with DV‐PIV, seemed to provide a better prediction of adverse cardiovascular outcome in FGR . A recent study by Dahlback et al showed that an increased S/v ratio was predictive of adverse outcome, and related to umbilical vein pulsations . A high S/v ratio implies a decrease in forward flow during ventricular end‐systole (ie isovolumetric relaxation time, v‐wave) as the pressure in the atria increases.…”

Ultrasound evaluation of the fetal venous ductus and its clinical applications in the current Obstetrics

“…En contraste con las alteraciones en la arteria umbilical y la arteria cerebral media, que son signos tempranos de resultados adversos, los estudios longitudinales han demostrado que las formas de onda del flujo de DV se vuelven anormales solo en estadios avanzados de compromiso fetal (59,60).…”

Mind the gap: fetal physiology from bench to bedside

“…Conversely, Dahlbäck et al . suggest that umbilical venous pulsations seem to better predict adverse outcome of pregnancy than do indices established in the ductus venosus. Such contradicting views may be due to the differences in the compliance of the various vascular beds being studied, particularly in the compromised fetus.…”

“…The group of Baschat (24) remind us that the study of waveforms in the ductus venosus has a critical role in directing the clinical management of fetuses at risk of cardiovascular deterioration. Conversely, Dahlb€ ack et al (25) suggest that umbilical venous pulsations seem to better predict adverse outcome of pregnancy than do indices established in the ductus venosus. Such contradicting views may be due to the differences in the compliance of the various vascular beds being studied, particularly in the compromised fetus.…”