定量组织速度成像测定右心室心肌等容舒张时间定量估测肺动脉收缩压

Pulmonary artery systolic pressure quantitatively evaluated by quantitative tissue velocity imaging acquiring right ventricular myocardium isovolumic relaxation time

目的探讨应用定量组织速度成像（QTVI）技术测定右室心肌等容舒张时间在定量估测肺动脉收缩压（PASP）中的价值。方法58例PAH患者人入选本研究。首先应用连续波多普勒超声估测PASP。在组织速度成像（TVI）条件下，获取标准心尖四腔切面、心尖右室流入道长轴切面的3个以上心动周期图像，离线分析右室游离壁、后壁、室间隔处的基底段、中间段组织速度曲线，测量右室3个壁6个节段心肌收缩期运动曲线终末点至舒张期起始点的时限（IVRt），将IVRt占1个心动周期的百分比（IVRt／RR）作为其标准化值。以右室各节段IVRt／RR的平均值作为右室心肌整体等容舒张时间（IVRt／RR）。应用超声心动图检查24h内对入选者行右心导管检查，测定PASP。结果多普勒超声法较右心导管法测量的PASP低（12．59±4．68）mmHg（P〈0．05）。右室各节段IVRt／RR和IVRt／RR与PASP均具有良好的相关性（r=0．60～0．78，P〈0．01～0．001），其中，右室游离壁中间段IVRt／RR和IVRt／RR与PASP相关性更好。以IVRt／RR〉17％或IVRt／RR〉17%判定中-重度肺动脉高压具有较高的准确性。结论右室心肌IVRt／RR是定量估测PASP的可靠准确技术。

Objective To evaluate pulmonary artery systolic pressure （PASP） by quantitative tissue velocity imaging （QTVI） acquiring right ventricular （RV） myocardium isovolumic relaxation time. Methods Fifty-eight patients with PAH were studied by normal echocardiography, QTVI and right cardiac catheterization. The regional velocity profiles of 6 segments of RV along RV apical long axis view and four chamber view were obtained. The time （IVRt） from end of systolic profiles to onset of next diastolic profiles of all RV 6 segments were measured. PASP were measured by Doppler echocardiography and right cardiac catheterization. Results PASP by Doppler echocardiography were lower than those by right cardiac catheterization [（12.59±4.68） mmHg, P〈0.05]. There were good correlation between RV all segments myocardium IVRt/RR, IVRt/RR and PASP （r=0. 60-0. 78, P〈0.01-0. 001）. There were better correlation between RV free wall media myocardium IVRt/RR, IVRt/RR and PASP. When a cut off value of 17% of IVRt/RR was used to detect a PASP above 60 mm- Hg, the sensitivity and specificity was 86.84% and 80.00% respectively. And When a cut off value of 17% of IVRt/RR of RV free wall media myocardium was used to detect a PASP above 60 mmHg, the sensitivity and specificity was 81.58% and 75.00% respectively. Conclusion RV myocardium IVRt/RR is a reliable and accurate technique for quantitatively evaluating PASP.