Sattarzadeh Roya, Tavoosi Anahita, Saadat Mohammad, Derakhshan Leila, Khosravi Bakhtyar, Geraiely Babak
Department of Cardiology, Imam Khomeini Hospital, Tehran University of Medical Sciences, Tehran, Iran.
Department of Pediatrics, Imam Khomeini Hospital, Tehran University of Medical Sciences, Tehran, Iran.
Acta Med Iran. 2017 Nov;55(11):696-704.
Accurate measurement of Mitral Valve Area (MVA) is essential to determining the Mitral Stenosis (MS) severity and to achieving the best management strategies for this disease. The goal of the present study is to compare mitral valve area (MVA) measurement by Continuity Equation (CE) and Pressure Half-Time (PHT) methods with that of 2D-Planimetry (PL) in patients with moderate to severe mitral stenosis (MS). This comparison also was performed in subgroups of patients with significant Aortic Insufficiency (AI), Mitral Regurgitation (MR) and Atrial Fibrillation (AF). We studied 70 patients with moderate to severe MS who were referred to echocardiography clinic. MVA was determined by PL, CE and PHT methods. The agreement and correlations between MVA's obtained from various methods were determined by kappa index, Bland-Altman analysis, and linear regression analysis. The mean values for MVA calculated by CE was 0.81 cm (±0.27) and showed good correlation with those calculated by PL (0.95 cm, ±0.26 ) in whole population (r=0.771, P<0.001) and MR subgroup (r=0.763, P<0.001) and normal sinus rhythm and normal valve subgroups (r=0.858, P<0.001 and r=0.867, P<0.001, respectively). But CE methods didn't show any correlation in AF and AI subgroups. MVA measured by PHT had a good correlation with that measured by PL in whole population (r=0.770, P<0.001) and also in NSR (r=0.814, P<0.001) and normal valve subgroup (r=0.781, P<0.001). Subgroup with significant AI and those with significant MR showed moderate correlation (r=0.625, P=0.017 and r=0.595, P=0.041, respectively). Bland Altman Analysis showed that CE would estimate MVA smaller in comparison with PL in the whole population and all subgroups and PHT would estimate MVA larger in comparison with PL in the whole population and all subgroups. The mean bias for CE and PHT are 0.14 cm and -0.06 cm respectively. In patients with moderate to severe mitral stenosis, in the absence of concomitant AF, AI or MR, the accuracy of CE or PHT method in measuring MVA is nearly equal. But in the presence of significant AI or MR, PHT method is obviously superior to CE and in the presence of AF neither have sufficient accuracy.
准确测量二尖瓣面积（MVA）对于确定二尖瓣狭窄（MS）的严重程度以及制定针对该疾病的最佳管理策略至关重要。本研究的目的是比较连续性方程（CE）和压力减半时间（PHT）法与二维平面测量法（PL）测量中重度二尖瓣狭窄（MS）患者二尖瓣面积（MVA）的差异。这种比较也在伴有严重主动脉瓣关闭不全（AI）、二尖瓣反流（MR）和心房颤动（AF）的患者亚组中进行。我们研究了70例转诊至超声心动图门诊的中重度MS患者。通过PL、CE和PHT法测定MVA。通过kappa指数、Bland-Altman分析和线性回归分析确定从各种方法获得的MVA之间的一致性和相关性。在总体人群（r = 0.771，P < 0.001）、MR亚组（r = 0.763，P < 0.001）、正常窦性心律和正常瓣膜亚组（分别为r = 0.858，P < 0.001和r = 0.867，P < 0.001）中，CE法计算的MVA平均值为0.81 cm（±0.27），与PL法计算的结果（0.95 cm，±0.26）显示出良好的相关性。但CE法在AF和AI亚组中未显示出相关性。PHT法测量的MVA与PL法测量的结果在总体人群（r = 0.770，P < 0.001）、正常窦性心律亚组（r = 0.81 , P < 0.001）和正常瓣膜亚组（r = 0.781，P < 0.001）中具有良好的相关性。伴有严重AI和伴有严重MR的亚组显示出中度相关性（分别为r = 0.625，P = 0.017和r = 0.595，P = 0.041）。Bland Altman分析表明，在总体人群和所有亚组中，CE法估计的MVA比PL法小，PHT法估计的MVA比PL法大。CE和PHT的平均偏差分别为0.14 cm和 -0.06 cm。在中重度二尖瓣狭窄患者中，在没有合并AF、AI或MR的情况下，CE或PHT法测量MVA的准确性几乎相等。但在存在严重AI或MR的情况下，PHT法明显优于CE法，而在存在AF的情况下，两者都没有足够的准确性。
