多普勒组织能量图在犬实验性心肌挫伤早期诊断中的价值

Doppler tissue energy(DTE) imaging in the early diagnosis on dogs with experimental myocardial contusion

目的探讨多普勒组织能量图(DTE)在心肌挫伤早期诊断中的价值。方法选取杂种犬8只,采用BIM-Ⅱ型水平撞击机制成心肌挫伤模型。分别在伤前及伤后0.5、2、48、h行超声心动图检查,并与病理TTC心肌染色结果对照分析。结果心肌挫伤后,DTE显示室间隔、左室前壁、侧壁、后壁及心尖部心肌活动消失,呈黑色,与紫红色正常心肌间有明显分界。此外,DTE显示心肌挫伤后心肌坏死面积随时间增加而增加,伤后0.5、24、h差异有显著性(P<0.01),4 h与8 h间差异无显著性(P>0.05)。伤后8 h,DTE所示心肌坏死面积[(5.65±1.06)cm2]大于病理所测心肌坏死面积[(4.74±0.61)cm2],P<0.01,但二者间高度相关。结论DTE能够较准确地反映心肌挫伤的程度及部位。

Objective To investigate the role of DTE in the early diagnosis on dogs with experimental myocardial contusion. Methods Eight dogs were selected and anaesthetized with 3% pentobarbital sodium intravenous injection, and then impacted by BIM - Ⅱ biological impact machine for the establishment of myocardial contusion （MC）. Doppler tissue energy （DIE） imaging was used to detect the degree and area of injuries of the myocardial tissues after myocardial contusion. Its results were then compared with pathological TIC staining method. All the observation time phases were set as before impact and 0.5h, 2h, 4h and 8h after impact injuries. Restilts Doppler tissue energy had revealed that the normal ventficular wall were purple colored, while the injured ventricular wall were black colored and without wall motions, mainly concentrated at ventricular wall segments as interventricular septum, left ventricular front wall, out- side wall, back wall and the apical wall, and more over, the injured myocardial tissue areas increased as time elongated. At 8 hours post MC, the injured tissue areas measured by DTE were wider than that confirmed by pathology, however, they were well correlated. Conclusion DTE technique of the echocardiography may provide a more accurate way in the detection of the concrete damaged sites, areas or degrees of myocardial contusion.