负荷超声心动图在犬心肌挫伤诊断中的价值

目的研究负荷超声心动图在犬实验性重度心肌挫伤后心肌损伤程度判定中的应用价值.方法选取杂种犬10只,3%戊巴比妥钠静脉麻醉,采用BIM-Ⅱ型生物撞击机制成心肌挫伤模型.常规监测动物生命体征(包括呼吸、心率、血压等)的变化.常规及负荷超声心动图观察心肌挫伤后心肌的节段性运动异常并与病理氯化三苯基四氮唑(TTC)染色结果对照.结果常规二维超声心动图与负荷超声心动图均显示心肌挫伤(MC)后,部分心肌节段出现矛盾运动或室壁瘤.这些节段主要为前间壁、中间壁和前外侧壁等.MC后室壁运动评分及室壁节段运动指数(WMSI)均较伤前明显增加.与病理TTC染色结果对照证实,常规超声心动图诊断挫伤心肌的敏感度为100%,特异性为66.67%;负荷超声心动图诊断挫伤心肌的敏感性为100%,特异性为88.89%.结论负荷超声心动图在心肌挫伤的检出中具有更高的特异性,临床应用的价值更大.

Stressed echocardiography in the diagnosis of dogs with myocardial contusion

Objective To investigate the role of dobutamine induced stressed echocardiography in the assessment of experimental myocardial contusion (MC).Methods Ten dogs were selected and anaesthetized with 3% pentobarbitorium sodium intravenous injection, and then impacted by BIM-II biological impact machine for the establishment of myocardial contusion (MC). The respiratory rate HR), heart rate (HR) and blood pressure (BP) were conventionally observed. Conventional and stressed echocardiography were used for observing segmental abnormal ventricular wall motions, and these results were finally compared with pathological TTC staining.Results It was revealed by both conventional and stressed echocardiography that parts of ventricular wall were demonstrated with segmental abnormal motions or even ventricular aneurysm. These segments mainly distributed at front interventricular wall, middle interventricular wall and side-front ventricular wall. After MC, the ventricular wall motion scoring and wall motion segment index (WMSI) increased remarkably than that of before MC. Comparison with TTC staining, it was demonstrated that conventional echocardiography had a sensitivity of 100% and a specificity of 66.67%; meanwhile, stressed echocardiography had a sensitivity of 100% and a specificity of 88.89%.Conclusion Stressed echocardiography may have a higher specificity in the diagnosis of myocardial contusion and a higher clinical value.