Assessment of cardiac function by magnetic resonance imaging.

Magnetic resonance imaging (MRI) is a unique and insightful tool for the assessment of physiology and function in congenital heart disease, in both the preoperative and postoperative state. MRI can accurately measure the volume and mass of unusual ventricular shapes, perform myocardial tissue and blood tagging, and can measure velocity and flow using phase-encoded velocity mapping. This has added new dimensions to research in pediatric cardiology. Newer techniques such as oxygen-sensitive MRI and echo-planar MRI promise further advances in the field. This article describes contemporary MRI studies of the physiology of complex congenital heart disease.