心肌声学造影时间-强度曲线参数定量评价心肌血流灌注的重复性研究

Reproducibility Study on Quantitative Assessment of Myocardial Perfusion by the Parameters of Time-Intensity Curve with Myocardial Contrast Echocardiography

目的 评价心肌声学造影时间 强度曲线 (TIC)在定量心肌血流灌注时的各项参数测量的重复性。方法 对 12条犬于注射乙酰胆碱 (Ach)前、后分别重复进行心肌声学造影 ,采用声学密度定量 (AD)技术获取TIC各项参数 ,计算注射Ach前、后即静息和冠脉最大扩张时各项参数的变异系数。结果 随冠脉血流 (CBF)增加 ,TIC参数中峰值强度 (PI)、曲线下面积 (AUC)和曲线下降斜率 (DS )明显增加 ,峰值时间 (TP)、峰值减半时间 (HT )和造影剂平均通过时间 (MTT)明显减小 ,P值均小于 0 .0 0 0 1。在静息和冠脉最大扩张两种状态下 ,TP、PI和MTT的重复性较好 ,变异系数分别为 13 .0 0 %、14 .99%、15 .5 0 % (静息 )和 10 .84%、16.12 %、19.5 8% (冠脉最大扩张 ) ,而HT、AUC和DS的变异系数次之 ,静息和冠脉最大扩张时分别为 2 0 .3 8%、2 2 .5 3 %、2 5 .82 %、和 17.12 %、2 5 .72 %、2 6.0 9%。结论 采用AD技术获得心肌声学造影TIC ,其各项参数的测量重复性较好 ,技术稳定 ,为心肌声学造影评价局部心肌血流灌注提供定量方法 。

Objective To evaluate the reproducibility of quantitative assessmetnt of myocardial perfusion by time intensity curve (TIC) with myocardial contrast echocardiography. Methods The parameters of TIC were obtained by acoustic densitometry (AD) technology pre and post acetylcholine (Ach) injection in 12 dogs. Coefficient of variation (CV) of parameters derived from TIC was calculated pre and post ach injection (base and coronary artery extreme relaxation). Results With increasement of coronary blood flow (CBF), peak intensity (PI), area under the curve (AUC) and descending slope (DS) were increased siginificantly but time to peak (TP), half time of descent (HT) and mean transit time (MTT) were decreased siginificantly, P <0.0001. The better reproducibility of parameters were TP, PI and MTT, the CV was 13.00%, 14.99%, 15.50%(base)and 10.84%,16.12%,19.58% (coronary artery extreme relaxation) respectively. The variance of HT, AUC and DS was bigger, the CV was 20.38%,22.53%,25.82% (base) and 17.12%,25.72%,26.09%(coronary artery extreme relaxation) respectively. Conclusion The repeated measurements of parameters derived from TIC with myocardial contrast echocardiography were stable. TIC was a kind of useful method of quantitative assessment of regional myocardial perfusion on base and coronary artery extreme relaxation.