Department of Obstetrics and Gynaecology, University Hospital Brugmann, Brussels, Belgium.
Ultrasound Obstet Gynecol. 2012 Mar;39(3):322-9. doi: 10.1002/uog.10061. Epub 2012 Feb 8.
To evaluate prospectively the feasibility of magnetic resonance imaging (MRI) for assessment of the fetal heart for congenital heart disease (CHD).
This was a cross-sectional study, including 66 fetuses with a normal heart and 40 with CHD. The fetal heart was examined on MRI using axial steady-state free precession (SSFP) sequences. Regression analysis was used to investigate the effect on the ability to visualize cardiac anatomy of gestational age at examination, maternal body mass index, presence of fetal cardiac abnormality, fetal movements, fetal lie and twinning. The sensitivity and specificity of detecting cardiac defects were calculated.
The four-chamber view was visualized in 98.1% of fetuses. The sensitivity of detecting a cardiac defect on the four-chamber view was 88% and the specificity 96%. The ability to visualize the left and right outflow tracts was only influenced by the presence of fetal movements: for the left outflow tract 94.4 vs. 50.0% visualization and for the right outflow tract 92.6 vs. 53.8% visualization without and with fetal movements, respectively. The sensitivity of detecting a cardiac defect of the left outflow tract was 63% and the specificity 100%, while sensitivity and specificity were 59 and 97%, respectively, for the right outflow tract.
Despite the use of SSFP sequences, MRI in the fetal heart remains of limited value. It can only be used as a second-line approach for abnormalities of the four-chamber view suspected at prenatal ultrasound.
前瞻性评估磁共振成像（MRI）在评估先天性心脏病（CHD）胎儿心脏方面的可行性。
这是一项横断面研究，包括 66 例心脏正常胎儿和 40 例 CHD 胎儿。使用轴位稳态自由进动（SSFP）序列对胎儿心脏进行 MRI 检查。回归分析用于研究检查时的胎龄、母亲体重指数、胎儿心脏异常、胎儿运动、胎儿位置和双胞胎对心脏解剖结构可视化能力的影响。计算检测心脏缺陷的敏感性和特异性。
四腔心视图在 98.1%的胎儿中可见。四腔心视图检测心脏缺陷的敏感性为 88%，特异性为 96%。左、右流出道的可视化能力仅受胎儿运动的影响：左流出道无胎儿运动时的可视化率为 94.4%，有胎儿运动时为 50.0%；右流出道无胎儿运动时的可视化率为 92.6%，有胎儿运动时为 53.8%。左流出道检测心脏缺陷的敏感性为 63%，特异性为 100%，而右流出道的敏感性和特异性分别为 59%和 97%。
尽管使用了 SSFP 序列，MRI 对胎儿心脏的应用仍具有一定的局限性。它只能作为产前超声怀疑四腔心视图异常的二线方法。
