Chen Q, Nosir Y F, Vletter W B, Kint P P, Salustri A, Roelandt J R
Thoraxcenter, University Hospital, Rotterdam, The Netherlands.
J Am Soc Echocardiogr. 1997 Mar;10(2):133-40. doi: 10.1016/s0894-7317(97)70085-3.
The accuracy of measurements of mitral valve orifice area (MVA) from three-dimensional echocardiographic (3DE) image data sets obtained by a transthoracic or transesophageal rotational imaging probe was studied in 15 patients with native mitral stenosis. The smallest MVA was identified from a set of eight parallel short-axis cut planes of the mitral valve between the anulus and the tips of leaflets (paraplane echocardiography) and measured by planimetry. In addition, MVA was measured from the two-dimensional short-axis view (2DE). Values of MVA measured by 3DE and 2DE were compared with those calculated from Doppler pressure half-time (PHT) as a gold standard. Observer variabilities were studied for 3DE. MVA measured from PHT ranged between 0.55 and 3.19 cm2 (mean +/- SD 1.57 +/- 0.73 cm2), from 3DE between 0.83 and 3.23 cm2 (mean +/- SD 1.55 +/- 0.67 cm2), and from 2DE between 1.27 and 4.08 cm2 (mean +/- SD 1.9 +/- 0.7 cm2). The variability of intraobserver and interobserver measurements for 3DE measurements was not significantly different (p = 0.79 and p = 0.68, respectively); for interobserver variability, standard error of the estimate = 0.25. There was excellent correlation, close limits of agreement (mean difference +/- 2 SD), and nonsignificant differences between 3DE and PHT for MVA measurements (r = 0.98 [0.02 +/- 0.3] and p = 0.6), respectively. There was moderate correlation, wider limits of agreement, and significant difference between 2DE and PHT for MVA measurements (r = 0.89 [0.32 +/- 0.66] and p = 0.002), respectively. This may be related to the difficulties in visualization of the smallest orifice in precordial short-axis views. This study suggests that three-dimensional image data sets, by providing the possibility of "computer slicing" to generate equidistant parallel cross sections of the mitral valve independently from physically dictated ultrasonic windows, allow accurate and reproducible measurement of the MVA.
对15例原发性二尖瓣狭窄患者，研究了经胸或经食管旋转成像探头获取的三维超声心动图（3DE）图像数据集测量二尖瓣口面积（MVA）的准确性。从二尖瓣瓣环与瓣叶尖端之间的一组八个平行短轴切面（旁平面超声心动图）中确定最小的MVA，并通过平面测量法进行测量。此外，还从二维短轴视图（2DE）测量MVA。将3DE和2DE测量的MVA值与根据多普勒压力半衰期（PHT）计算的值进行比较，PHT作为金标准。研究了3DE测量的观察者变异性。根据PHT测量的MVA范围在0.55至3.19 cm²之间（平均±标准差1.57±0.73 cm²），3DE测量的范围在0.83至3.23 cm²之间（平均±标准差1.55±0.67 cm²），2DE测量的范围在1.27至4.08 cm²之间（平均±标准差1.9±0.7 cm²）。3DE测量的观察者内和观察者间测量的变异性无显著差异（分别为p = 0.79和p = 0.68）；对于观察者间变异性，估计标准误差 = 0.25。对于MVA测量，3DE与PHT之间存在极好的相关性、相近的一致性界限（平均差异±2标准差）且无显著差异（r = 0.98 [0.02±0.3]，p = 0.6）。对于MVA测量，2DE与PHT之间存在中度相关性、较宽的一致性界限且有显著差异（r = 0.89 [0.32±0.66]，p = 0.002）。这可能与心前区短轴视图中最小瓣口可视化困难有关。本研究表明，三维图像数据集通过提供“计算机切片”的可能性，独立于物理规定的超声窗口生成二尖瓣的等距平行横截面，从而能够准确且可重复地测量MVA。
