Standardized Acquisition of Fetal Cardiac Cine MRI: A Practical Guide.

Abstract

Fetal ultrasound is the primary screening modality for routine prenatal examinations, but its effectiveness can be influenced by factors such as maternal body habitus, polyhydramnios, or fetal position. Although magnetic resonance imaging (MRI) is well established for fetal brain and body imaging, cardiac assessment has been restricted by the absence of reliable cardiac gating and motion compensation strategies. Only recently have advances in fetal cardiac rhythm monitoring within the MRI scanner enabled retrospective gating, paving the way for clinical use of fetal cardiac MRI. However, a reproducible and standardized imaging protocol for systematic cardiac assessment on cine sequences has not yet been universally adopted. This article proposes a practical framework for fetal cardiac cine MRI acquisition and interpretation based on a segmental approach consistent with standard fetal echocardiographic orientations, while also incorporating ungated T2-weighted imaging with slice-to-volume reconstruction for the assessment of extracardiac vascular anatomy. Representative cases with annotated anatomic landmarks illustrate how MRI can be integrated into a multimodality prenatal imaging strategy. The development of a standardized protocol may facilitate reproducibility across centers and support the incorporation of fetal cardiac MRI as a complementary tool within comprehensive prenatal cardiac evaluation.