Del Río M, Martínez J M, Figueras F, Bennasar M, Olivella A, Palacio M, Coll O, Puerto B, Gratacós E
Department of Maternal-Fetal Medicine, ICGON, Hospital Clínic, University of Barcelona and Centre for Biomedical Research on Rare Diseases (CIBERER), Barcelona, Spain.
Ultrasound Obstet Gynecol. 2008 Jan;31(1):41-7. doi: 10.1002/uog.5237.
To evaluate the characteristics and association with perinatal outcome of the aortic isthmus (AoI) circulation as assessed by Doppler imaging in preterm growth-restricted fetuses with placental insufficiency.
This was a prospective cross-sectional study. Fifty-one fetuses with intrauterine growth restriction (IUGR) and either an umbilical artery (UA) pulsatility index (PI) > 95(th) centile or a cerebroplacental ratio < 5(th) centile were examined at 24-36 weeks' gestation. AoI impedance indices (PI and resistance index) and absolute velocities (peak systolic (PSV), end-diastolic and time-averaged maximum (TAMXV) velocities), were measured in all cases and compared with reference ranges by gestational age. Furthermore, fetuses were stratified into two groups according to the direction of the diastolic blood flow in the AoI: those with antegrade flow (n = 41) and those with retrograde flow (n = 10). Clinical surveillance was based on gestational age and Doppler assessment of the UA, middle cerebral artery and ductus venosus (DV). Adverse perinatal outcome was defined as stillbirth, neonatal death and severe morbidity (respiratory distress syndrome, bronchopulmonary dysplasia, Grade III/IV intraventricular hemorrhage, necrotizing enterocolitis and a neonatal intensive care unit stay > 14 days).
Adverse perinatal outcome was significantly associated with an increased AoI-PI (area under the curve 0.77; 95% CI, 0.63-0.92; P < 0.005). A significant correlation (P < 0.001) was found between retrograde blood flow in the AoI and adverse perinatal outcome, the overall perinatal mortality being higher in the retrograde group (70% vs. 4.8%, P < 0.001). In 4/5 (80%) fetuses the reversal of flow in the AoI preceded that in the DV by 24-48 h. AoI-PSV and AoI-TAMXV were < 5(th) centile in 40/51 (78%) and 48/51 (94%) cases, respectively, whereas AoI-PI was > 95(th) centile in 21/51 (41%) cases.
Retrograde flow in the AoI in growth-restricted fetuses correlates strongly with adverse perinatal outcome. Absolute velocities in the AoI are decreased in growth-restricted fetuses. The data suggest a potential role for Doppler imaging of the AoI in the clinical surveillance of fetuses with severe IUGR, which should be confirmed in larger prospective studies.
通过多普勒成像评估胎盘功能不全的早产生长受限胎儿主动脉峡部（AoI）循环的特征及其与围产期结局的关联。
这是一项前瞻性横断面研究。对51例宫内生长受限（IUGR）胎儿进行检查，这些胎儿脐动脉（UA）搏动指数（PI）>第95百分位数或脑胎盘比率<第5百分位数，妊娠24 - 36周。测量所有病例的AoI阻抗指数（PI和阻力指数）以及绝对速度（收缩期峰值速度（PSV）、舒张末期速度和时间平均最大速度（TAMXV）），并与按胎龄划分的参考范围进行比较。此外，根据AoI舒张期血流方向将胎儿分为两组：正向血流组（n = 41）和反向血流组（n = 10）。临床监测基于胎龄以及对UA、大脑中动脉和静脉导管（DV）的多普勒评估。不良围产期结局定义为死产、新生儿死亡和严重疾病（呼吸窘迫综合征、支气管肺发育不良、III/IV级脑室内出血、坏死性小肠结肠炎以及新生儿重症监护病房住院时间>14天）。
不良围产期结局与AoI - PI升高显著相关（曲线下面积0.77；95%可信区间，0.63 - 0.92；P < 0.005）。发现AoI反向血流与不良围产期结局之间存在显著相关性（P < 0.001），反向血流组的总体围产期死亡率更高（70%对4.8%，P < 0.001）。在4/5（80%）的胎儿中，AoI血流逆转比DV血流逆转提前24 - 48小时。40/51（78%）和48/51（94%）的病例中，AoI - PSV和AoI - TAMXV分别<第5百分位数，而21/51（41%）的病例中AoI - PI >第95百分位数。
生长受限胎儿的AoI反向血流与不良围产期结局密切相关。生长受限胎儿的AoI绝对速度降低。数据表明AoI多普勒成像在严重IUGR胎儿的临床监测中可能具有潜在作用，这应在更大规模的前瞻性研究中得到证实。
