斑点追踪成像技术评价犬急性缺血再灌注左室功能

目的探讨二维斑点追踪成像(STI)技术测量实验犬的等容收缩期加速度指标在评价左室功能方面的价值。方法将14只健康杂种犬建立急性心肌梗死再灌注模型,分别于基础状态,结扎即刻、30 min、120 min、180 min及再灌注即刻、60 min、120 min行超声心动图检查,应用STI技术测量并计算左室心肌等容收缩期径向加速度和圆周加速度。结果缺血节段的等容收缩期圆周加速度和径向加速度自梗死30 min开始降低,且随梗死时间延长而减低(均P0.05);恢复再灌注后,各梗死节段的等容收缩期加速度逐渐升高(均P0.05)。结论二维STI技术所测等容收缩期加速度指标可定量评价犬急性缺血再灌注引起的心肌节段性室壁运动异常,为评价左室收缩功能提供有价值的信息。

Assessment of left ventricular function in dogs after acute ischemia-reperfusion by two-dimensional speckle tracking imaging

Objective To assess the value of isovolumic contraction acceleration （ICA） in evaluation of canine left ventricular function by two-dimensional speckle tracking imaging（STI）. Methods Acute myocardial infarction and reperfnsion model was established in 14 dogs. Echocardiography was applied on baseline, immediately after ligation, 30 min, 120 min, 180 min after ligation and immediately after reperfusion, 60 min, 120 min after reperfusion. STI was performed to measure the left ventricular（ LV ） radial and circumferential ICA. Results The radial and circumferential ICA of ischemia segments was decreased 30 min after infarction. It was gradually decreased with the prolongation of infarction time （P〈0.05）. After reperfusion, the ICA was gradually increased（P〈0.05 ）. Conclusion Two-dimensional STI technology could quantitatively evaluate segmental wall motion abnormalities in dogs after acute ischemia-reperfusion, which provids useful information for evaluation of LV systolic function.