Department of Cardiology, Kawasaki Medical School, Kurashiki, Japan.
J Cardiol. 2009 Feb;53(1):94-101. doi: 10.1016/j.jjcc.2008.09.005. Epub 2008 Nov 8.
The degree of mitral valve (MV) coaptation should be an important parameter in the assessment of functional mitral regurgitation (MR). This study aimed to quantify the degree of MV coaptation in experimental models of functional MR caused by acute left ventricular (LV) pressure overload, using real-time three-dimensional (3D) echocardiography.
Using canine models, LV pressure overload was induced by staged ascending aortic banding. Echocardiographic examinations were performed before and during the aortic banding. By using a novel software system for 3D quantification (REALVIEW®), the annulus and leaflet were traced manually both at the onset of MV closure and at the maximum MV closure. The coaptation index was calculated by the following formula: [(3D tenting surface area at the onset of MV closure-3D tenting surface area at the maximum MV closure)/3D tenting surface area at the onset of MV closure] x 100. MR area gradually increased with the decrease in coaptation index during progressively exacerbated aortic banding. MR area was significantly correlated with the coaptation index. A coaptation index < 12 had a high sensitivity and specificity in the presence of significant MR.
The degree of MV coaptation can be quantified using 3D echocardiography. The coaptation index should be a useful parameter in the assessment of functional MR.
二尖瓣（MV）的对合程度应该是评估功能性二尖瓣反流（MR）的一个重要参数。本研究旨在使用实时三维（3D）超声心动图定量评估由急性左心室（LV）压力超负荷引起的功能性 MR 实验模型中的 MV 对合程度。
使用犬模型，通过逐步升主动脉缩窄术诱导 LV 压力超负荷。在主动脉缩窄前后进行超声心动图检查。通过使用一种用于 3D 定量的新型软件系统（REALVIEW®），手动追踪 MV 关闭起始时和 MV 关闭最大时的瓣环和瓣叶。通过以下公式计算对合指数：[(MV 关闭起始时的 3D 隆起表面积-MV 关闭最大时的 3D 隆起表面积)/MV 关闭起始时的 3D 隆起表面积] x 100。随着主动脉缩窄逐渐加重，MR 面积逐渐增大，而对合指数逐渐减小。MR 面积与对合指数显著相关。在存在明显 MR 的情况下，对合指数<12 具有较高的敏感性和特异性。
可以使用 3D 超声心动图定量评估 MV 的对合程度。对合指数应该是评估功能性 MR 的一个有用参数。
