Klinik und Poliklinik für Innere Medizin II, Universitätsklinikum Regensburg, Regensburg, Germany.
JACC Cardiovasc Imaging. 2011 Oct;4(10):1088-96. doi: 10.1016/j.jcmg.2011.06.020.
This study sought to characterize the shape of regurgitant orifice area (ROA) and mitral apparatus in various forms of mitral regurgitation (MR) by cardiac magnetic resonance (CMR).
ROA is an accepted parameter of MR severity. However, there are little data on the shape of the ROA in various forms of MR.
Direct assessment of ROA was performed with a 1.5-T CMR scanner using a breath-hold fast imaging with steady-state free precession. The regurgitant orifice shape and the anatomy of the mitral valve apparatus including mitral annulus, mitral leaflet angles, and mitral valve tenting area were assessed.
We studied 74 patients. MR severity was mild in 39%, moderate in 27%, and moderate-to-severe or severe in 34%. Mitral valve pathology was degenerative in 26%, prolapse in 22%, flail in 33%, and functional in 19%. For all patients, ROA correlated significantly with regurgitant fraction (r = 0.80, p < 0.001). The ROA shape index as expressed by the ratio of the larger length to the smaller length was a median of 2.04 (interquartile range [IQR]: 1.49 to 3.08) over all patients. CMR revealed significant asymmetry of the ROA geometry in functional MR 3.91 (IQR: 2.79 to 4.84) compared with prolapse 2.14 (IQR: 1.80 to 3.04), flail 2.20 (IQR: 1.69 to 2.91), and degenerative MR 1.24 (IQR: 1.09 to 1.57), all p < 0.01. The assessment of mitral valve geometry demonstrated that patients with functional MR had significantly increased leaflet angles, mitral valve tenting area, and mitral annulus area (all p < 0.05). Of note, the orifice shape index correlated with increasing leaflet angles in patients with functional MR (r = 0.68, p = 0.005).
Direct assessment of ROA by CMR revealed significant asymmetry of ROA in various forms of MR, particularly in patients with functional MR. The slitlike appearance in functional MR correlates with a distended mitral apparatus.
本研究旨在通过心脏磁共振（CMR）对各种形式的二尖瓣反流（MR）的瓣环反流口面积（ROA）和二尖瓣装置的形状进行特征描述。
ROA 是评估 MR 严重程度的一个公认参数。然而，关于各种形式的 MR 中 ROA 的形状的数据很少。
使用 1.5-T CMR 扫描仪，通过屏气快速稳态自由进动成像直接评估 ROA。评估反流口的形状以及二尖瓣装置的解剖结构，包括二尖瓣环、二尖瓣瓣叶角度和二尖瓣瓣叶膨出面积。
我们研究了 74 例患者。MR 严重程度为轻度 39%、中度 27%、中重度或重度 34%。二尖瓣病变为退行性 26%、脱垂 22%、连枷样 33%、功能性 19%。对于所有患者，ROA 与反流分数显著相关（r = 0.80，p < 0.001）。ROA 形状指数（用较大长度与较小长度的比值表示）在所有患者中的中位数为 2.04（四分位距 [IQR]：1.49 至 3.08）。CMR 显示，与脱垂（2.14，IQR：1.80 至 3.04）、连枷样（2.20，IQR：1.69 至 2.91）和退行性 MR（1.24，IQR：1.09 至 1.57）相比，功能性 MR 的 ROA 几何形状明显不对称 3.91（IQR：2.79 至 4.84），所有 p < 0.01。二尖瓣几何结构的评估表明，功能性 MR 患者的瓣叶角度、二尖瓣瓣叶膨出面积和二尖瓣环面积显著增加（均 p < 0.05）。值得注意的是，在功能性 MR 患者中，瓣口形状指数与瓣叶角度的增加呈正相关（r = 0.68，p = 0.005）。
CMR 对 ROA 的直接评估显示，各种形式的 MR 的 ROA 明显不对称，尤其是在功能性 MR 患者中。功能性 MR 中的缝隙样外观与扩张的二尖瓣装置相关。
