Role of Fetal Cardiac MRI in Assessment of Congenital Heart Diseases in Comparison to Fetal Echocardiography

Abstract

Introduction •Abnormalities of the cardiovascular system are the most common congenital diseases in the fetus and the first cause of infant mortality (Johnson et al. 2014). •Without a doubt, Echocardiography is the method of choice to visualize the fetal cardiac cardiovascular abnormalities. Unlike fetal echocardiography imaging, cardiovascular magnetic resonance (CMR) is relatively unaected by maternal and fetal conditions such as maternal obesity, uterine myoma, twins, oligohydramnios, fetal position and rib calcification, which particularly impair sonographic visualization of the fetal heart (Donofrio et al. 2014; Wielandner et al. 2013). •Fetal cardiac MR imaging is a novel MRI technique which can provide valuable information that could add to the prenatal diagnosis and evaluation of cardiac and most of extra-cardiac anomalies. The evaluation of pre-natal congenital cardiac anomalies is important for postnatal management. Aim of the work To highlight the advantage of MRI over fetal echocardiography in assessment of fetal congenital cardiac anomalies. Methods and material Twenty-six feti with suspected or diagnosed congenital cardiac anomalies. All cases underwent detailed history taking, fetal echocardiography and fetal cardiac MR. Study is approved by the ethics review board of Ain Shams University Hospital. Fetal echocardiography was done according to standard protocol and performed by suitable curvilinear probe. Then MRI of the fetal heart was done with uterine SURVEY_BFFE (balanced fast field echo), Black blood single shot -BH, white blood Cine, sBFFE_RLT DYN 3D(real time 3Ddynamic). Images were acquired in the transverse, four-chamber, shortaxis, coronal and oblique sagittal views. Findings of fetal echocardiography were compared with that of cardiac MRI. Results •Regarding the diagnostic performance of prenatal Echo and fetal cardiac MRI showed significant moderate agreement between the two modalities in the detection of different congenital cardiac anomalies, Kappa test: 0.500; p-value 0.021*. •Qualitative analysis: All cardiac structures were delineable by echocardiography and cardiac MRI. There was full agreement(κ = 1) between fetal echocardiography and cardiac MRI in evaluating the cardiac situs(24normal,1 levocardia, 1 ectopia cordis), aorta (20normal, 3 hypoplastic aorta,1 aortic stenosis,1 rt. Sided aortic arch and 1 small sized aorta), transverse cardiac diameter (22 normal, 4 cardiomegaly), foramen ovale (25 normal, 1 large single atrium), Good agreement was found between echocardiography and cardiac MRI for detection of position of the cardiac apex (23 normal, 2 dextrocardia and 1 mesocardia) •Fetal MRI had a significant role in detection of additional extracardiac anomalies in 13 cases. Conclusion fetal cardiac MR imaging as an adjunct to fetal echocardiography may provide valuable information that could add to the prenatal diagnosis and evaluation of cardiac and most of extra cardiac anomalies.