Recovery of Myocardial Perfusion and Left Ventricular Wall Motion Abnormality after Recanalization of Obstructed Coronary Artery

本研究旨在揭示冠脉梗阻再通后心肌灌注的恢复情况，并结合局部壁运动异常。心肌超声造影评价心肌灌注。冠脉床通过导管注射造影剂染色。根据感兴趣区域的时间强度曲线计算峰值强度和对比洗净率。在犬模型中，冠状动脉血流在再通后很快明显增加。然而，再灌注区造影剂的冲洗率延迟。洗脱率与冠状动脉血流的增加呈负相关。这表明造影剂冲洗率越差，反应性充血的增量越小。此外，在造影剂冲洗率延迟的情况下，壁运动异常的延迟恢复也被注意到。心肌微循环受损越严重，异常运动恢复越慢。在临床研究中，对心肌梗死患者的心肌超声造影资料与201-铊心肌显像资料进行比较。超声心动图也显示壁运动异常。大多数患者的心肌灌注评价与核医学评价吻合较好。然而，在一些患者中，通过铊显像评估的灌注缺损区域被对比超声染色。这个部分起初表现为运动不全，但几个月后变为运动不全。结果表明，mri与超声对心肌灌注的评价具有临床意义。

The aim of this study is to reveal the recovery of myocardial perfusion after recanalization of obstructed coronary artery with reference to regional wall motion abnormalities. Myocardial contrast echocardiography was used to assess the myocardial perfusion. The coronary bed was stained by injected contrast agents through a catheter. Peak intensity and washout rate of contrast were calculated from time intensity curve in the area of interest. In the canine model, the coronary flow increased significantly soon after recanalization. However, the washout rate of contrast from the reperfused area was delayed. The washout rate was correlated inversely with the increment of coronary flow. This indicates that the worse the washout rate of contrast, the smaller the increment of reactive hyperemia. Also, delayed recovery of the wall motion abnormality was noted in cases with delayed washout rate of contrast. The more significant the microcirculation of myocardium was impared, the slower the abnormal motion was recovenred. In the clinical study, the data of myocardial contrast echocardiography was compared with those of 201-Thallium myocardial scintigraphy in patients with myocardial infaction. Wall motion abnormalities were also by echocardiography. The evaluation of myocardial perfusion was correspondent well between contrast echo and nuclear medicine in most patients. In some patients, however, the perfusion defect area assessed by Thallium scintigraphy was stained by contrast echography. This segment had shown a kinesis at first, but became hypokinetic after months. It is revealed that the difference of the evaluation of myocardial perfusion assessed by RI and echo is clinically significant.