MRI provides a non-invasive diagnostic tool complementing echocardiography on one hand, and showing advantages over echocardiography, on the other hand, especially after corrective procedures. The multiple different MRI sequences need to be adapted to examinations of children and patients with congenital heart disease (CHD), and can be used to detect morphologic changes, blood-flow in the heart and thoracic vessels and diastolic or systolic function of myocardium. Several factors determine the success of the examination of a complex congenital heart disease or a postoperative situs. Pediatric radiologists and radiologists experienced in congenital heart diseases have to work in close cooperation. Echocardiography should be performed before MRI. The results of prior examinations and the clinical history of the patients, including possible palliative or reconstructive operations, must be available before MRI to guide the planning of the examination. With a systematic segmental approach to the situs, to the atrial and ventricular morphology, and to the visceroatrial, atrioventricular and ventriculoarterial connections, most CHDs can be diagnosed correctly. With appropriate knowledge, MRI can also be performed quite accurately after complex operations and may avoid or delay invasive diagnostic procedures. The aim of this article is to impart knowledge, to mention problems and to provide guidance in the performance of cardiac MRI in patients with CHD.
