Radiologists are using magnetic resonance imaging (MRI) and computed tomography (CT) as methods of examining the heart and cardiovascular system. MRI is safe and non-invasive, and it has become a widely used diagnostic tool for many forms of heart disease. The cardiac CT, also non-invasive, is an X-ray that can help detect artherosclerosis of the coronary arteries. Both procedures help in the diagnosis of a variety of cardiovascular problems and in the planning of treatment.