A review of the complementary information available with cardiac magnetic resonance imaging and multi-slice computed tomography (CT) during the study of congenital heart disease.

The incidence of congenital heart disease is approximately 4-6 per 1000 new births; however, the number of people living with congenital heart disease (CHD) is increasing, because of improved diagnosis, medical, and surgical management. While echocardiography continues to be the mainstay of non-invasive imaging, cardiac MRI (cMRI) and computed tomography (CT) have taken on increasing roles in the diagnosis of congenital heart disease in infants, children, and importantly, adults who may have limited echocardiographic windows, especially if post-operative. Cardiac MRI and multi-slice CT can complement the diagnostic information obtained by echocardiography and invasive cardiac catheterization. Post-operative imaging of CHD is especially enhanced by the spin echo MRI techniques, while gradient cine echo MRI imaging allows functional information that is not encumbered by geometric assumptions. Phase contrast (velocity encoding) cardiac MRI data can provide information about flow, allowing accurate determination of regurgitation and shunt volume. Gadolinium enhanced cMRI or three-dimensional reconstructed images from multi-slice CT angiography allow excellent delineation of vascular structures in complex heart disease. Coronary imaging, while possible with both modalities, appears more facile with fast CT imaging. This article reviews the literature to provide an assessment of the special techniques and considerations needed during the conduct of cardiac MRI/MRA and multi-slice CT examinations during the diagnosis of congenital heart disease in pediatric and adult patients.