Value of fetal heart diameter Z-score in prediction of homozygous α-thalassemia-1 at mid-pregnancy / 中华超声影像学杂志

ABSTRACT

Objective To evaluate the efficacy of fetal heart diameter(HD)Z-score as predictors of homozygous α-thalassemia-1.Methods Two hundred and fourteen cases of Single mid-pregnancies(1 5-22 W)at risk of homozygous α-thalassemia-1 were enrolled.Fetal HD were first measured.Next,the Z-scores of HD were calculated separately based on previously constructed Z-score models.Finally,the accuracy of this variable was analyzed and compared with that from the cardiothoracic ratio(CTR)by ROC curves analysis.Results ①A total of 214 singleton pregnancies were recruited in which 57 cases were homozygous α-thalassemia-1 fetuses and the other 157 cases were unaffected.②The affected fetal HD and Z-score were significantly higher than those in the unaffected fetuses(P <0.01).③With the HD Z-score >2.76 as the best cutoff value,the sensitivity and specificity of predicting homozygous α-thalassemia-1 fetuses in 1 5-22 gestational week were 92.98% and 100%;If a best cut-off value of CTR >0.52 was used for prediction,the sensitivity was 87.72% and the specificity was 91.72%.Compared with CTR,the discriminative power of HD Z-score was better(Z value=2.286,P <0.01).Conclusions HD Z-score is a novel,effective and noninvasive predictor of homozygous α-thalassemia-1 in mid-pregnancy.Its prediction efficiency is higher than that of traditional CTR.It can improve the prenatal detection rate of homozygous α-thalassemia-1 fetus,reduce unnecessary invasive operation and save expenses.