瓣环扩大在功能性二尖瓣返流机制中的作用

Effect of mitral annular dilation in the mechanism of functional mitral regurgitation

目的探讨瓣环扩大在功能性二尖瓣返流机制中的作用。方法应用超声心动图检查房颤组(20例)、返流组(30例)及正常组(20例)的心脏,测量二尖瓣返流比例、左室射血分数(EF)、左室大小、球形度、收缩期瓣环(MA)面积、收缩期后乳头肌与二尖瓣前瓣环的距离(PPMAMA)。结果房颤组左室大小、球形度、EF、PPMAMA和正常组相比没有统计学差异,但收缩期MA面积较正常组明显扩大,并与返流组相似,分别为(5.3±1.1)cm2、(7.4±1.5)cm2、(8.0±2.0)cm2,但房颤组二尖瓣返流量明显小于功能性二尖瓣返流组,分别为(12±7)%和(30±14)%。结论单纯瓣环的扩张似乎并不引起中或重度二尖瓣返流。

Objective To investigate the effect of mitral annular （MA） dilation in the mechanism of functional mitral regurgitation （FMR）. Methods Jet/left atrial area, mid-systolic MA area, left ventricular （LV） volumes, systolic L/D, ejection fraction （EF） and leaflet tethering length between the posterior papillary muscle tips and contralateral anterior MA （PPM-AMA） were compared by echocardiography among 20 control subjects, 20 patients with lone atrial fibrillation （AF group） and 30 patients with coronary artery disease or dilated cardiomyopathy （FMR group）. Results LV size, EF, systolic L/D and PPM-AMA in AF group were similar to those in normal group, but MA dilated significantly in AF group and which was comparable to that of FMR group （MA area： [5.3±1.1] cm^2 , [7.4±1.5] cm^2 , [8.0±2.0] cm^2）. However, AF group only had modest MR, which was smaller than FMR group （MR fraction： [12±73]%, [30±14]%）. Conclusion Isolated annular dilation does not seem to cause moderate or severe MR.