速度向量成像技术评价房间隔缺损患者右心室节段收缩功能

目的探讨速度向量成像技术评价房间隔缺损及修补术前后右心室壁节段收缩功能的价值。方法对29例单纯房间隔缺损患者（I组）修补术前后、10例房间隔缺损合并肺动脉高压患者（Ⅱ组）及17例正常对照组，分别采用心肌速度向量成像技术观察心尖四腔心切面右心室游离壁和室间隔基底段、中段和心尖段收缩期峰值速度、应变和应变率。结果I组术前右心室壁各节段收缩期峰值速度高于I组术后、Ⅱ组和对照组（P〈0．05），而收缩期峰值应变、应变率高于Ⅱ组，但与I组术后、对照组相比差异无统计学意义（P〉0．05）。I组术后收缩峰值速度、应变与应变率与对照组相比差异无统计学意义（P〉0．05）。Ⅱ组右心室壁各节段收缩峰值速度、应变、应变率均低于对照组（P〈0．05或P〈0．01）。结论右心室收缩期峰值速度易受容量负荷的影响，而收缩期峰值应变和应变率更能真正反映右心室收缩功能。速度向量成像技术能准确定量评价房间隔缺损患者右心室壁节段收缩功能的变化，有望成为评价右心室收缩功能的新方法。

Evaluation of regional right ventricular systolic function in patients with atrial septum defect by velocity vector imaging

Objective To assess right ventricular regional systolic function by using velocity vector imaging （VVI） in patients before and after the closure of atrial septum defect （ASD）. Methods A total of 39 patients with ASD were classified into group I （ patients without pulmonary hypertension） and group Ⅱ （patients with pulmonary hypertension）. Seventeen patients were chosen as controls group. Myocardial sys- tolic peak velocity, strain and strain rate were observed at basal, mid and apical segments of the right ven- tricular free wall and ventricular septum by VVI. Results The myocardial systolic peak velocity of grouplwas higher than that after ASD closure ,that of group Ⅱ and control group（ P 〈 0.05 ）. The systolic peak strain and strain rate of group Iwere higher than that of group Ⅱand showed no difference compared with that of control group and that after ASD closure（P 〉 0.05 ）. There were no difference in systolic peak velocity, strain and strain rate between patients after ASD closure and controls group（ P 〉 0.05 ）. The myocardial systolic peak ve- locity, strain and strain rate of group Ⅱwere significantly impaired compared with the control group （P 〈 0.05 or P 〈0.01 ）. Conclusions The peak systolic myocardial velocity of right ventricular can be affected with preload, while myocardial peak systolic strain and strain rate of right ventricular were more reliable. The new velocity vector imaging, which can provide accurate quantization of changes in regional right ventricular systolic function caused by ASD, is a useful tool for assessing the right ventricular systolic function.