A cardiac MRI provides high–quality still and moving images of the heart and other internal structures without the exposure to X–rays. This type of imaging is often used to evaluate the cardiovascular system. It not only provides a snapshot of the heart, but the beating of it as well. This helps physicians assess any abnormalities in the contraction of the cardiac chamber, blood flow and function of the "great" vessels.
Your physician will decide the most effective test for you and your particular need.