Rizzo G, Capponi A, Arduini D, Romanini C
Department of Obstetrics and Gynecology, Università di Roma Tor Vergata, Policlinico Nuovo S. Eugenio, Italy.
Early Hum Dev. 1994 Sep 30;39(1):15-26. doi: 10.1016/0378-3782(94)90066-3.
The objective of this study was to evaluate differences in ductus venosus velocity waveforms between appropriate and small for gestational age fetuses by using a new index based on the ratio between systolic and atrial peak velocities. Ductus venosus velocity waveforms were cross-sectionally recorded in 164 appropriate for gestational age fetuses at 16-42 weeks of gestation and in 97 small for gestational age fetuses free from structural and chromosomal abnormalities between 24-36 weeks of gestation. Small for gestational age fetuses were divided according to the Doppler findings in arterial peripheral vessels: group A (n = 33), normal ratio between umbilical artery and middle cerebral artery Pulsatility Indices; group B (n = 41), umbilical artery/middle cerebral artery ratio > 95th centile but presence of end diastolic flow in umbilical artery; group C (n = 23), umbilical artery/middle cerebral artery ratio > 95th centile and absence of end diastolic flow in umbilical artery. Eighteen small for gestational age fetuses (10 from group B and 8 from group C) were also serially studied until delivery due to fetal distress. Ductus venosus velocity waveforms were recorded at the level of its origin from umbilical vein and the ratio between systolic and atrial peak velocities (systolic/atrial ratio) calculated. In appropriate for gestational age fetuses, systolic/atrial ratio values significantly decrease with gestation. No significant differences were found in systolic/atrial ratio between appropriate for gestational age fetuses and group A small for gestational age fetuses while, after correction for gestational age, significantly higher values were found in group B (P < or = 0.01) and group C (P < or = 0.001) fetuses. Among these fetuses, those with systolic/atrial ratio above the 95th confidence interval showed a poorer perinatal outcome. No relationships were found between systolic/atrial ratio and Pulsatility Index values from fetal arterial peripheral vessels, while a positive relationship was found with the percentage reverse flow in inferior vena cava. In fetuses serially followed, the systolic/atrial ratio progressively increased approaching the onset of abnormal fetal heart rate patterns. The systolic/atrial ratio allows the evaluation of ductus venosus hemodynamics in small for gestational age fetuses and this index may be useful in the monitoring of such fetuses.
本研究的目的是通过使用基于收缩期与心房峰值速度之比的新指标，评估适于胎龄儿和小于胎龄儿之间静脉导管速度波形的差异。在妊娠16 - 42周的164例适于胎龄儿以及妊娠24 - 36周无结构和染色体异常的97例小于胎龄儿中，对静脉导管速度波形进行横断面记录。小于胎龄儿根据动脉外周血管的多普勒检查结果进行分组：A组（n = 33），脐动脉与大脑中动脉搏动指数比值正常；B组（n = 41），脐动脉/大脑中动脉比值>第95百分位数，但脐动脉存在舒张末期血流；C组（n = 23），脐动脉/大脑中动脉比值>第95百分位数且脐动脉无舒张末期血流。18例小于胎龄儿（10例来自B组，8例来自C组）因胎儿窘迫也被连续研究直至分娩。在静脉导管起源于脐静脉的水平记录静脉导管速度波形，并计算收缩期与心房峰值速度之比（收缩期/心房比值）。在适于胎龄儿中，收缩期/心房比值随孕周显著降低。适于胎龄儿与A组小于胎龄儿的收缩期/心房比值无显著差异，而在校正孕周后，B组（P≤0.01）和C组（P≤0.001）胎儿的收缩期/心房比值显著更高。在这些胎儿中，收缩期/心房比值高于第95置信区间的胎儿围产期结局较差。收缩期/心房比值与胎儿动脉外周血管的搏动指数值之间未发现相关性，而与下腔静脉的反向血流百分比呈正相关。在连续随访的胎儿中，收缩期/心房比值在异常胎儿心率模式出现前逐渐升高。收缩期/心房比值可用于评估小于胎龄儿的静脉导管血流动力学，该指标可能有助于监测此类胎儿。
