Evaluation of valvular heart disease with cine gradient echo magnetic resonance imaging.

Electrocardiographic referenced repetitive gradient echo magnetic resonance imaging (cine GRE) has been used to detect and quantify valvular regurgitation. Regurgitation is recognized as a signal void in the high intensity blood pool on these images. Mitral regurgitation causes a signal void in the left atrium in systole, and aortic regurgitation produces one in the left ventricle in diastole. The specificity, sensitivity, and diagnostic accuracy of cine GRE for the detection of mitral and aortic regurgitation was greater than 0.93, 0.89, and 0.92, respectively. The severity of regurgitation has been quantified as the difference in the stroke volume between the two ventricles by measuring the volume of the blood pool, as shown in the stack of magnetic resonance tomograms. Severity has also been assessed by measuring the volume of the signal void. Finally, measurements of the volume of aortic regurgitation have recently been achieved by using velocity-encoded cine GRE. This technique provides a direct measurement of retrograde flow in the aorta during diastole. New cine GRE imaging techniques provide a noninvasive means for quantification of valvular as well as ventricular function.