孕中期左心发育不良综合征胎儿的肺动脉血流参数特征的价值

目的探讨孕中期左心发育不良综合征（HLHS）胎儿肺动脉血流参数特征。 方法选取2015年8月至2017年5月在南京医科大学附属苏州医院确诊HLHS胎儿54例，将中孕期HLHS胎儿按照其房间隔血流模式分为血流通畅组（41例）与梗阻组（13例），并与正常胎儿（健康对照组，55例）在肺动脉主干内径、右肺动脉内径和右肺动脉第一级分支血流频谱参数3个层面进行对比，采用LSD-t检验分析通畅型和梗阻型HLHS胎儿的肺动脉内径、收缩期峰值流速（PSV）、舒张期末期速度（EDV）、平均速度（TAMXV）、速度-时间积分（VTI）和肺动脉搏动指数（PA PI）等血流参数特征。 结果肺动脉主干内径方面，三组间均值比较（5.4±0.6 vs 6.7±0.8 vs 6.8±0.9），差异有统计学意义（F=198.56，P<0.05），且通畅组和梗阻组的肺主干内径均大于健康对照组，差异均有统计学意义（t=-18.501、-13.97，P均<0.05），而通畅组和梗阻组的均值比较，差异无统计学意义（P=0.85）；右肺动脉内径方面，三组间均值比较，差异无统计学意义（P=0.59）；右肺动脉第一级分支血流频谱参数方面，三组间在PSV比较，差异无统计学意义（P=0.34），而在EDV、TAMXV、VTI和PA PI方面，差异均有统计学意义（F=62.98、38.45、13.19及12.46，P均<0.05），且通畅组和梗阻组胎儿EDV、TAMXV和VTI均值小于健康对照组，差异均有统计学意义（t=4.273和10.353、3.546和7.978、-0.441和5.418，P均<0.05），且梗阻组均值小于通畅组，差异均有统计学意义（t=5.542、7.033及4.098，P均<0.05）；而通畅组和梗阻组HLHS胎儿PA PI均值大于健康对照组，差异均有统计学意义（t=-2.638、-6.474，P均<0.05），且梗阻组大于通畅组，差异均有统计学意义（t=-2.541，P<0.05）。 结论HLHS胎儿肺动脉分支血流前向阻力增加，且房间隔血流梗阻型相对于通畅型表现更为显著，这可能与梗阻型肺血管床受损程度相对较重有关。

Characteristics of branch pulmonary artery flow patterns in fetuses with left heart hypoplasia syndrome in the second trimester

ObjectiveTo explore the characteristics of branch pulmonary artery flow patterns in fetuses with left heart hypoplasia syndrome (HLHS). MethodsHLHS fetuses were divided into an unobstructed group and an obstructed group according to the blood flow pattern across the interatrial septum. Main pulmonary artery diameter, right pulmonary artery diameter, and Doppler parameters of first-order right pulmonary artery of both groups were measured by fetal echocardiography and compared with those of normal controls. ResultsThere was a significant difference in the diameter of pulmonary trunk among different the three groups (F=198.56, P<0.05), and the main pulmonary artery diameter in the two groups of HLHS fetuses were larger than that in normal controls (t=-18.501, -13.97, P<0.05), but there was no significant difference between the two groups of HLHS fetuses (P=0.85). There was no significant difference in right pulmonary artery diameter among the three groups (P=0.59). The end-diastolic velocity, time-averaged maximum velocity, and velocity-time integral in the two HLHS groups were lower than those in normal controls, and these parameters in the obstructed group were less than those in the unobstructed group. The pulmonary artery pulsatility index in the two HLHS groups was higher than those in normal controls, and it was higher in the obstructed group than in the unobstructed group. There was no statistically significant difference in peak systolic velocity among the three groups (P=0.34). ConclusionThe antegrade resistance of the pulmonary arteries of HLHS fetuses increase and these pathologcial conditions are more obvious in those with obstructed flow across the atrial septum compared to those with unobstructed flow.