Congenital heart disease (CHD) is the most common of all major congenital anomalies and affects around 9 out of 1000 live births. Mortality rates have been reduced, but CHD is still the second most frequent cause of neonatal death. To prepare parents and doctors in a timely and suitable fashion for open heart surgery of a newborn with significant CHD, the abnormality needs to be diagnosed as early as possible during pregnancy. Fetal echocardiography has significantly improved antenatal diagnosis of CHD, but is not always conclusive. Fetal cardiac MRI (CMR) has the potential to provide a conclusive second opinion when challenges such as motion of the fetus, limited spatial resolution, motion of maternal breathing and the difficulty of synchronizing the CMR acquisition to the fetal electrocardiogram (ECG) are mitigated. To advance the diagnostic capabilities and the application at younger gestational ages, we propose to improve current fetal CMR protocols by:
1) Establishing wider echo Doppler fields of view of a CMR-compatible fetal ECG recording device in order to facilitate the assessment of fetal motion and the cardiac signal for fetal CMR synchronization.
2) Designing technology for fast, motion-robust 6D flow CMR (fetal cardiac signal, maternal breathing and fetal motion on the 4th, 5th and 6th dimensions, respectively). Motion-compensated time-resolved 3D flow patterns will increase the diagnostic power of fetal CMR for intra-cardiac, valvular and great vessel abnormalities.
3) Designing technology for fast, motion-robust 4D anatomical (3D CINE) CMR. This will allow angulation of analysis planes in any direction for easier detection of cardiac anomalies and will shorten total anatomical scan time.
Testing of motion-robustness and reproducibility of the new technologies designed under objectives 1, 2 and 3 will be performed on 10 adult volunteers who will be instructed to perform various breathing and motion experiments in the CMR scanner and on 8 fetuses with CHD.
4) Validating these novel technologies in 10 fetal sheep. Fetal sheep experiments allow ad hoc adjustment of CMR parameters without unnecessary increasing scan burden for (human) pregnant mothers.
5) Implementing the novel CMR sequences in clinical practice as an addition to pre- and postnatal echocardiographic examinations and compare the CMR results with echocardiography in 60 human fetuses with CHD.