Didier D, Ratib O, Lerch R, Friedli B
Department of Radiology, Hôpital Cantonal Universitaire de Genève, 24 rue Micheli du Crest, 1211 Geneva 14, Switzerland.
Radiographics. 2000 Sep-Oct;20(5):1279-99; discussion 1299-301. doi: 10.1148/radiographics.20.5.g00jl111279.
Magnetic resonance (MR) imaging is rapidly gaining acceptance as an accurate, reproducible, noninvasive method for optimal assessment of structural and functional parameters in patients with valvular heart disease. The severity of valvular regurgitation can be evaluated with cine gradient-echo MR imaging, which allows measurement of the area of the signal void corresponding to the abnormal flow jet. Alternatively, this modality can be used to obtain ventricular volumetric measurements and calculate the regurgitant fraction, or velocity-encoded cine (VEC) MR imaging can be used to quantify regurgitant blood flow. The severity of valvular stenosis can be determined by evaluating the flow jet and associated findings with either modality or by using VEC MR imaging to calculate the transvalvular pressure gradient and valve area. Dynamic MR imaging allows accurate assessment of ventricular function and comprehensive evaluation of pathophysiologic changes. In addition, good interstudy reproducibility suggests a role for VEC MR imaging in assessing the effects of therapeutic intervention and monitoring regurgitant fraction, thereby helping in surgical planning and the prevention of ventricular dysfunction. With greater cost-effectiveness and the increasing availability of new hardware and more advanced techniques, MR imaging will become a routine procedure in valvular heart disease.
磁共振（MR）成像作为一种准确、可重复、无创的方法，用于对瓣膜性心脏病患者的结构和功能参数进行最佳评估，正迅速得到认可。瓣膜反流的严重程度可通过电影梯度回波MR成像进行评估，该成像可测量与异常血流喷射相对应的信号缺失区域。或者，这种方式可用于获取心室容积测量值并计算反流分数，或者速度编码电影（VEC）MR成像可用于量化反流血流。瓣膜狭窄的严重程度可通过评估任一方式的血流喷射及相关表现，或使用VEC MR成像计算跨瓣膜压力梯度和瓣膜面积来确定。动态MR成像可准确评估心室功能并全面评估病理生理变化。此外，良好的研究间可重复性表明VEC MR成像在评估治疗干预效果和监测反流分数方面具有作用，从而有助于手术规划和预防心室功能障碍。随着成本效益的提高以及新硬件和更先进技术的日益普及，MR成像将成为瓣膜性心脏病的常规检查方法。
