Visualization of aortic valve leaflets using black blood MRI.

ABSTRACT

Although magnetic resonance imaging (MRI) is capable of imaging various physiological parameters associated with the heart valves, it has generally been difficult to visualize the valve leaflets directly. The aortic valve was imaged in 120 patients referred for cardiac MRI to assess myocardial volumes or mass. The average patient age was 37 and ranged from 9 to 75 years. Heart rate ranged from 43 to 100 bpm. Imaging was performed on a 1.5 T scanner equipped with enhanced gradients and a cardiac phased-array coil. A double inversion recovery fast spin-echo sequence was used to acquire short-axis images of the aortic valve in a breath-hold (15 +/- 3 seconds). All three leaflets of the aortic valve were seen in 102 of 120 studies (85%). Two leaflets were detected in another 15 subjects. No leaflets were seen in three individuals. Seven cases of a bicuspid or thickened aortic valves were clearly distinguished from normal valves. The signal-to-noise ratio of aortic leaflets (14 +/- 5) was significantly higher than that of the residual blood signal in the aortic root (7 +/- 4, P < 0.001). MR images showed the aortic valve leaflets in a high fraction of people with suspected normal aortic valves and detected seven cases of abnormal aortic valves. The potential of MRI to study both the anatomic and functional consequences of valvular heart disease warrants further study. J. Magn. Reson. Imaging 1999;10771-777.