Children's Heart Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.
Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.
Ultrasound Obstet Gynecol. 2018 Oct;52(4):479-487. doi: 10.1002/uog.18936.
As birth weight is a critical predictor of outcome in neonates with congenital heart defect (CHD), the common problem of poor fetal growth in this population is clinically important. However, it is not well understood and the impact of fetal hemodynamics on fetal growth and birth weight in those with CHD has not been assessed. In this study, we sought to evaluate the association between combined cardiac output (CCO) and fetal middle cerebral artery (MCA) and umbilical artery (UA) pulsatility indices (PIs) and fetal growth in different subgroups of CHD, and to study the effects of fetal hemodynamics on late gestational weight gain. We hypothesized that fetuses with CHD will have lower CCO and be smaller at birth.
This was a retrospective review of fetal echocardiograms from 67 fetuses diagnosed with hypoplastic left heart syndrome (HLHS, n = 30), non-HLHS single ventricle (SV) (n = 20) or dextrotransposition of the great arteries (d-TGA, n = 17), compared with normal controls (n = 42). CCO was calculated using valvar area, velocity-time integral and heart rate and indexed to estimated fetal weight. MCA- and UA-PI were calculated using systolic, diastolic and mean velocities. Fetal biometry was recorded. Regression models were used to study trends in CCO, MCA- and UA-PI and fetal biometry over gestational age. To evaluate fetal weight gain in late gestation, Z-scores of estimated fetal weight at 30 weeks and birth weight were compared. Regression analysis was used to determine the associations of CCO, indexed CCO and MCA- and UA-PI at 30 weeks with birth weight, length and head circumference Z-scores, in addition to weight gain late in gestation. The gestational age of 30 weeks was chosen based on previous studies that found evidence of poor weight gain in fetuses with CHD in late gestation, starting at around that time.
CCO increased with gestation in all four groups but the rate was slower in fetuses with HLHS and in those with SV. MCA-PI was lower in fetuses with HLHS compared with in those with non-HLHS-SV throughout gestation, suggesting different cerebral blood distribution. At the end of gestation, rate of fetal weight gain slowed in those with HLHS and in those with SV (similar to CCO curves), and head circumference growth rate slowed in all groups but controls. CCO, indexed CCO and MCA- and UA-PI did not correlate with any of the birth measurements or with weight gain late in gestation in fetuses with CHD.
We found no associations of CCO or MCA- and UA-PI with late gestational weight gain or biometry at birth in fetuses with CHD. This does not support fetal hemodynamics as the primary driver of suboptimal fetal growth in fetuses with SV. Future research could further explain genetic and placental abnormalities that may affect fetal growth in those with CHD. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.
由于出生体重是新生儿先天性心脏病（CHD）结局的关键预测因素，因此该人群中胎儿生长不良这一常见问题在临床上非常重要。然而，目前对此了解甚少，也尚未评估 CHD 胎儿血流动力学对胎儿生长和出生体重的影响。本研究旨在评估不同 CHD 亚组中合并心输出量（CCO）与胎儿大脑中动脉（MCA）和脐动脉（UA）搏动指数（PI）之间的关系，并研究胎儿血流动力学对晚期妊娠体重增加的影响。我们假设 CHD 胎儿的 CCO 较低，出生时体型较小。
这是对 67 例诊断为左心发育不全综合征（HLHS，n=30）、非 HLHS 单心室（SV，n=20）或右位主动脉弓（d-TGA，n=17）胎儿的胎儿超声心动图进行的回顾性研究，与正常对照组（n=42）进行比较。CCO 通过瓣口面积、速度-时间积分和心率计算，并与估计胎儿体重指数。MCA-和 UA-PI 通过收缩期、舒张期和平均速度计算。记录胎儿生物测量值。使用回归模型研究 CCO、MCA-和 UA-PI 以及胎儿生物测量值随胎龄的变化趋势。为了评估晚期妊娠时的胎儿体重增加，比较 30 周时估计胎儿体重的 Z 分数和出生体重。回归分析用于确定 30 周时 CCO、指数化 CCO 和 MCA-和 UA-PI 与出生体重、长度和头围 Z 分数的关系，以及晚期妊娠时的体重增加。选择 30 周的胎龄是基于之前的研究，这些研究发现 CHD 胎儿在晚期妊娠时体重增加不良的证据，大约从那时开始。
CCO 在所有 4 组中随胎龄增加而增加，但 HLHS 胎儿和 SV 胎儿的增加速度较慢。整个孕期，HLHS 胎儿的 MCA-PI 均低于非 HLHS-SV 胎儿，表明脑血流分布不同。妊娠末期，HLHS 胎儿和 SV 胎儿的胎儿体重增加速度减慢（与 CCO 曲线相似），而所有组的头围生长速度减慢，但对照组除外。CHD 胎儿的 CCO、指数化 CCO 和 MCA-和 UA-PI 与出生时的任何测量值或晚期妊娠时的体重增加均无相关性。
我们没有发现 CHD 胎儿的 CCO 或 MCA-和 UA-PI 与晚期妊娠体重增加或出生时的生物测量值相关。这并不支持胎儿血流动力学是 SV 胎儿胎儿生长不良的主要驱动因素。未来的研究可以进一步解释可能影响 CHD 胎儿胎儿生长的遗传和胎盘异常。版权所有©2017 ISUOG。由 John Wiley & Sons Ltd 出版。
