Functional evaluation of the heart with magnetic resonance imaging.

This review examines the capability of cine MRI for evaluation of cardiovascular function and shows early results in valvular, ischemic, and congenital heart disease. MR assessment of left and right ventricular volumes is independent of geometrical models; dimensional values have been defined for normal individuals. Noninvasive measurement of peak and end systolic pressure along with cine MR imaging can be used to calculate left ventricular meridional wall stress which can be used for monitoring of myocardial diseases and evaluation of therapeutic intervention. Cine MR may be more accurate than angiography for identifying regional LV dysfunction since it can measure wall thickening as well as inward wall motion. Regurgitant jets due to valvular lesions are readily seen and their characteristics may be used to define the severity of aortic or mitral regurgitation. Calculation of the regurgitant volume separates patients with mild, moderate, or severe disease. Likewise, the shunt flow across ventricular and atrial septal defects has been visualized in cine MR images and shunt flow calculated. Cine MRI serves as a three-dimensional imaging technique with high temporal resolution. It extends the capability of MRI in cardiac disease beyond the depiction of anatomy and renders a comprehensive cardiac imaging technique for quantitation of cardiac anatomy and function.