Fernandes Valerian, Olmos Leopoldo, Nagueh Sherif F, Quiñones Miguel A, Zoghbi William A
Section of Cardiology, Department of Medicine, Baylor College of Medicine, and The DeBakey Heart Center, Houston, Texas 77030, USA.
Am J Cardiol. 2002 Mar 15;89(6):704-10. doi: 10.1016/s0002-9149(01)02343-8.
Reliable screening of mechanical prosthetic mitral valve (PMV) dysfunction by transthoracic echocardiography (TTE) is mandatory because transesophageal echocardiography (TEE) cannot be routinely used. However, acoustic shadowing seriously hampers detection of PMV dysfunction with TTE, particularly regurgitation. To identify TTE indexes that can detect PMV dysfunction (regurgitation or obstruction), 134 patients (age 60 +/- 12 years, 64 men) with PMV who underwent TTE and TEE within 3 +/- 5 days were assessed. There were 73 normal and 61 dysfunctional valves (40 regurgitant, 21 obstructive). By multivariate analysis, peak E velocity was the best predictor of a dysfunctional valve. Both peak E velocity (E > or =1.9 m/s; sensitivity 92%, specificity 78%) and the ratio of velocity-time integrals of flow through the prosthesis to that of the left ventricular outflow (VTI(pmv/)VTI(lvo) > or =2.2; sensitivity 91%, specificity 74%) were successful in detecting PMV dysfunction. Although pressure half-time (PHT) readily identified PMV obstruction, it did not detect regurgitation. Logistic models including peak E velocity and VTI(pmv)/VTI(lvo) or PHT were equally successful in detecting PMV dysfunction. However, all 3 variables were needed to best distinguish among normal, obstructed, and regurgitant valves. A peak E velocity > or =1.9 m/s and VTI(pmv)/VTI(lvo) ratio > or =2.2 predicted valve regurgitation in 83% of valves when PHT was < 130 ms, and valve stenosis in 95% when PHT was >130 ms. Importantly, a peak E velocity < 1.9 m/s, VTI(pmv)/VTI(lvo) ratio < 2.2, and a PHT < 130 ms had a predictive accuracy for a normal valve of 98%. Thus, TTE Doppler indexes can be used as screening parameters of PMV dysfunction and help select patients for further diagnostic evaluation with TEE.
由于经食管超声心动图（TEE）无法常规使用，因此通过经胸超声心动图（TTE）对机械人工二尖瓣（PMV）功能障碍进行可靠筛查至关重要。然而，声学阴影严重妨碍了TTE对PMV功能障碍的检测，尤其是反流。为了确定能够检测PMV功能障碍（反流或梗阻）的TTE指标，对134例接受PMV的患者（年龄60±12岁，男性64例）进行了评估，这些患者在3±5天内接受了TTE和TEE检查。其中有73个瓣膜正常，61个功能障碍瓣膜（40个反流，21个梗阻）。通过多变量分析，E峰速度是功能障碍瓣膜的最佳预测指标。E峰速度（E≥1.9 m/s；敏感性92%，特异性78%）以及通过人工瓣膜的血流速度时间积分与左心室流出道血流速度时间积分的比值（VTI(pmv)/VTI(lvo)≥2.2；敏感性91%，特异性74%）均成功检测出PMV功能障碍。虽然压力半衰期（PHT）能很容易地识别PMV梗阻，但无法检测出反流。包含E峰速度和VTI(pmv)/VTI(lvo)或PHT的逻辑模型在检测PMV功能障碍方面同样成功。然而，需要所有这三个变量才能最佳地区分正常、梗阻和反流瓣膜。当PHT<130 ms时，E峰速度≥1.9 m/s和VTI(pmv)/VTI(lvo)比值≥2.2可预测83%的瓣膜反流；当PHT>130 ms时，可预测95%的瓣膜狭窄。重要的是，E峰速度<1.9 m/s、VTI(pmv)/VTI(lvo)比值<2.2以及PHT<130 ms对正常瓣膜的预测准确率为98%。因此，TTE多普勒指标可作为PMV功能障碍的筛查参数，并有助于选择患者进行进一步的TEE诊断评估。
