Sénéchal Mario, Michaud Nicolas, Machaalany Jimmy, Bernier Mathieu, Dubois Michelle, Magne Julien, Couture Christian, Mathieu Patrick, Bertrand Olivier F, Voisine Pierre
Department of Cardiology, Institut Universitaire de Cardiologie et de Pneumologie de Québec, Laval University, Chemin Sainte-Foy, Quebec G1V 4G5, Canada.
Cardiovasc Ultrasound. 2012 Jan 27;10:3. doi: 10.1186/1476-7120-10-3.
Mitral valve thickness is used as a criterion to distinguish the classical from the non-classical form of mitral valve prolapse (MVP). Classical form of MVP has been associated with higher risk of mitral regurgitation (MR) and concomitant complications. We sought to determine the relation of mitral valve morphology and motion to mitral regurgitation severity in patients with MVP.
We prospectively analyzed transthoracic echocardiograms of 38 consecutive patients with MVP and various degrees of MR. In the parasternal long-axis view, leaflets length, diastolic leaflet thickness, prolapsing depth, billowing area and non-coaptation distance between both leaflets were measured.
Twenty patients (53%) and 18 patients (47%) were identified as having moderate to severe and mild MR respectively (ERO = 45 ± 27 mm² vs. 5 ± 7 mm², p < 0.001). Diastolic leaflet thickness was similar in both groups (5.5 ± 0.9 mm vs. 5.3 ± 1 mm, p = 0.57). On multivariate analysis, the non-coaptation distance (OR 7.9 per 1 mm increase; 95% CI 1.72-37.2) was associated with significant MR. Thick mitral valve leaflet as traditionally reported (≥ 5 mm) was not associated with significant MR (OR 0.9; 95% CI 0.2-3.4).
In patients with MVP, thick mitral leaflet is not associated with significant MR. Leaflet thickness is probably not as important in risk stratification as previously reported in patients with MVP. Other anatomical and geometrical features of the mitral valve apparatus area appear to be much more closely related to MR severity.
二尖瓣厚度被用作区分经典型与非经典型二尖瓣脱垂（MVP）的标准。经典型MVP与更高的二尖瓣反流（MR）风险及相关并发症有关。我们试图确定MVP患者二尖瓣形态和运动与MR严重程度之间的关系。
我们前瞻性分析了38例连续的MVP及不同程度MR患者的经胸超声心动图。在胸骨旁长轴视图中，测量瓣叶长度、舒张期瓣叶厚度、脱垂深度、膨出面积及两瓣叶间的对合不良距离。
分别有20例（53%）和18例（47%）患者被确定为中度至重度和轻度MR（有效反流口面积分别为45±27mm²和5±7mm²，p<0.001）。两组舒张期瓣叶厚度相似（5.5±0.9mm对5.3±1mm，p=0.57）。多因素分析显示，对合不良距离（每增加1mm，OR为7.9；95%CI为1.72-37.2）与显著MR相关。传统报道的增厚二尖瓣瓣叶（≥5mm）与显著MR无关（OR为0.9；95%CI为0.2-3.4）。
在MVP患者中，增厚的二尖瓣瓣叶与显著MR无关。瓣叶厚度在MVP患者风险分层中的重要性可能不如先前报道的那样。二尖瓣装置的其他解剖和几何特征似乎与MR严重程度密切相关。
