Magnetic resonance imaging of fetal heart: anatomical and pathological findings

Congenital heart disease is one of the most frequent prenatal malformation representing an incidence of 5/1000 live births; moreover, it represents the first cause of death in the first year of life. There is a wide range of severity in congenital heart malformations from lesions which require no treatment such as small ventricular septal defects, to lesions which can only be treated with palliative surgery such as hypoplastic left heart syndrome. A good prenatal examination acquires great importance in order to formulate an early diagnosis and improve pregnancy management. Nowadays, echocardiography still represents the gold standard examination for fetal heart disease. However, especially when preliminary ultrasound is inconclusive, fetal MRI is considered as a third-level imaging modality. Preliminary experiences have demonstrated the validity of this reporting a diagnostic accuracy of 79%. Our article aims to outline feasibility of fetal MRI in the anatomic evaluation, the common indication to fetal MRI, its role in the characterization of congenital heart defects, and at last its main limitations.