Hogan W J, Moon-Grady A J, Zhao Y, Cresalia N M, Nawaytou H, Quezada E, Brook M, McQuillen P, Peyvandi S
Division of Pediatric Cardiology, Department of Pediatrics, The University of California San Francisco, San Francisco, CA, USA.
Division of Critical Care, Department of Pediatrics, The University of California San Francisco, San Francisco, CA, USA.
Ultrasound Obstet Gynecol. 2021 May;57(5):769-775. doi: 10.1002/uog.22024. Epub 2021 Apr 13.
Fetal cerebrovascular resistance is influenced by several factors in the setting of intact autoregulation to allow for normal cerebral blood flow and oxygenation. Maternal hyperoxygenation (MH) allows for acute alterations in fetal physiology and can be a tool to test cerebrovascular reactivity in late-gestation fetuses. In this study, we utilized MH to evaluate cerebrovascular reactivity in fetuses with specific congenital heart disease (CHD).
This was a cross-sectional study of fetuses with complex CHD compared to controls without CHD. CHD cases were grouped according to physiology into: left-sided obstructive lesion (LSOL), right-sided obstructive lesion (RSOL) or dextro-transposition of the great arteries (d-TGA). Subjects underwent MH testing during the third-trimester fetal echocardiogram. The pulsatility index (PI) was calculated for the fetal middle cerebral artery (MCA), umbilical artery (UA) and branch pulmonary artery (PA). The change in PI from baseline to during MH was compared between each CHD group and controls.
Sixty pregnant women were enrolled (CHD, n = 43; control, n = 17). In the CHD group, there were 27 fetuses with LSOL, seven with RSOL and nine with d-TGA. Mean gestational age was 33.9 (95% CI, 33.6-34.2) weeks. At baseline, MCA-PI Z-score was lowest in the LSOL group (-1.8 (95% CI, -2.4 to -1.2)) compared with the control group (-0.8 (95% CI, -1.3 to -0.3)) (P = 0.01). In response to MH, MCA-PI Z-score increased significantly in the control and d-TGA groups but did not change significantly in the LSOL and RSOL groups. The change in MCA-PI Z-score was significantly higher in the control group than in the LSOL group (0.9 (95% CI, 0.42-1.4) vs 0.12 (95% CI, -0.21 to 0.45); P = 0.03). This difference was more pronounced in the LSOL subgroup with retrograde aortic arch flow. Branch PA-PI decreased significantly in response to MH in all groups, with no difference in the change from baseline to MH between the groups, while UA-PI was unchanged during MH compared with at baseline.
The fetal cerebrovascular response to MH varies based on the underlying CHD diagnosis, suggesting that cardiovascular physiology may influence the autoregulatory capacity of the fetal brain. Further studies are needed to determine the clinical implications of these findings on long-term neurodevelopment in these at-risk children. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.
在完整的自动调节机制下，胎儿脑血管阻力受多种因素影响，以确保正常的脑血流量和氧合。母体高氧（MH）可引起胎儿生理的急性改变，可作为检测孕晚期胎儿脑血管反应性的一种手段。在本研究中，我们利用MH来评估患有特定先天性心脏病（CHD）胎儿的脑血管反应性。
这是一项对患有复杂CHD胎儿与无CHD对照组进行的横断面研究。CHD病例根据生理情况分为：左侧梗阻性病变（LSOL）、右侧梗阻性病变（RSOL）或大动脉右位转位（d-TGA）。在孕晚期胎儿超声心动图检查期间，对受试者进行MH测试。计算胎儿大脑中动脉（MCA）、脐动脉（UA）和肺动脉分支（PA）的搏动指数（PI）。比较各CHD组与对照组从基线到MH期间PI的变化。
共纳入60名孕妇（CHD组43例，对照组17例）。在CHD组中，有27例胎儿为LSOL，7例为RSOL，9例为d-TGA。平均孕周为33.9（95%CI，33.6 - 34.2）周。基线时，与对照组（-0.8（95%CI，-1.3至-0.3））相比，LSOL组的MCA-PI Z评分最低（-1.8（95%CI，-2.4至-1.2））（P = 0.01）。对MH的反应中，对照组和d-TGA组的MCA-PI Z评分显著增加，而LSOL组和RSOL组无显著变化。对照组MCA-PI Z评分的变化显著高于LSOL组（0.9（95%CI，0.42 - 1.4）对0.12（95%CI，-0.21至0.45）；P = 0.03）。这种差异在有主动脉弓逆流的LSOL亚组中更明显。所有组中，PA-PI对MH反应均显著降低，各组从基线到MH的变化无差异，而UA-PI在MH期间与基线相比无变化。
胎儿对MH的脑血管反应因潜在的CHD诊断而异，提示心血管生理可能影响胎儿脑的自动调节能力。需要进一步研究以确定这些发现对这些高危儿童长期神经发育的临床意义。©2020国际妇产科超声学会
