扩张型心室情况下缘对缘修复的疗效：一项体外研究。

Efficacy of the edge-to-edge repair in the setting of a dilated ventricle: an in vitro study.

作者信息

Croft Laura R, Jimenez Jorge H, Gorman Robert C, Gorman Joseph H, Yoganathan Ajit P

机构信息

Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0535, USA.

出版信息

Ann Thorac Surg. 2007 Nov;84(5):1578-84. doi: 10.1016/j.athoracsur.2007.05.086.

DOI:10.1016/j.athoracsur.2007.05.086

PMID:17954065

Abstract

BACKGROUND

The edge-to-edge repair to correct mitral regurgitation (MR) has shown substandard results in cases of ischemic MR or dilated cardiomyopathy.

METHODS

Ten porcine mitral valves were investigated in a left heart simulator (120 mm Hg, 5 L/min). Pathologic conditions of a dilated ventricle were simulated by using an annular model capable of three levels of dilation (normal, 56%, and 120%) and by displacing papillary muscles (PMs) 10 mm in the apical, lateral, and posterior directions. The edge-to-edge repair was performed; a central stitch was investigated for symmetric and asymmetric PM displacements, and a paracommissural stitch was investigated for asymmetric PM displacements. Left ventricular pressure and mitral flow rate were monitored, and regurgitation fraction was calculated from the mitral flow curve.

RESULTS

Under symmetric PM displacement, the repair reduced MR by 5.1% at dilation level one and by 9.1% at dilation level two. The repair decreased MR by 10.9% (dilation level two) after asymmetric displacement of the anterior-lateral PM, and by 5.4% (dilation level one) and 7.9% (dilation level two) after asymmetric displacement of the posterior-medial PM. The edge-to-edge repair reduced (p < 0.05) MR owing to annular dilation; however, it was unable to completely eliminate the MR. The repair did not significantly reduce MR caused by PM displacement, regardless of the displacement geometry. Stitch location did not affect repair efficacy.

CONCLUSIONS

The edge-to-edge repair is not an effective procedure in correcting MR associated with PM displacement, although it is able to partially reduce MR caused by annular dilation.

摘要

背景

用于纠正二尖瓣反流（MR）的缘对缘修复术在缺血性MR或扩张型心肌病病例中显示出不理想的结果。

方法

在左心模拟器（120 mmHg，5 L/min）中研究了10个猪二尖瓣。通过使用能够进行三级扩张（正常、56%和120%）的环形模型并将乳头肌（PMs）在心尖、外侧和后方方向移位10 mm来模拟扩张型心室的病理状况。进行缘对缘修复；研究了中央缝线用于对称和不对称PM移位的情况，以及旁连合缝线用于不对称PM移位的情况。监测左心室压力和二尖瓣流速，并根据二尖瓣血流曲线计算反流分数。

结果

在对称PM移位情况下，修复在一级扩张水平时将MR降低了5.1%，在二级扩张水平时降低了9.1%。在前外侧PM不对称移位后，修复使MR降低了10.9%（二级扩张水平），在后内侧PM不对称移位后降低了5.4%（一级扩张水平）和7.9%（二级扩张水平）。缘对缘修复因环形扩张降低了（p < 0.05）MR；然而，它无法完全消除MR。无论移位几何形状如何，修复均未显著降低由PM移位引起的MR。缝线位置不影响修复效果。