心肌挫伤诊断指标的实验研究

摘要

目的:探讨心肌挫伤的病理生理学改变,提出早期的诊断指标并评价相关指标的真实性及诊断价值.方法:选用新西兰大白兔36只,采用撞击法制备心前区闭合性损伤模型.测定伤前及伤后1、6、12、24、48 h的心电图、超声心动图、漂浮导管、肌钙蛋白Ⅰ、CK-MB改变,依据病理结果,将创伤动物分为心肌挫伤组和非心肌挫伤组,比较上述诊断指标最早出现阳性结果的时间及其真实性和诊断价值.结果:心肌挫伤后1 h心电图出现ST-T改变等非特异性改变且阳性结果动物数量最多,灵敏度为58.8%,特异度为75%,阴性预测值为56.2%.伤后1 h超声心动图提示EF下降、室壁异常运动、肺动脉估测压差升高等,伤后6 h阳性结果动物数量最多,灵敏度为93.3%,特异度为78.6%,阴性预测值为91.7%.漂浮导管检测提示,伤后1 h中心静脉压及肺动脉压明显升高且阳性结果动物数量最多,灵敏度为100%,特异度为83.3%,阴性预测值为100%.伤后6 h肌钙蛋白Ⅰ明显升高且阳性结果动物数量最多,灵敏度为94.1%,特异度为100%,阴性预测值为92.3%.伤后6 h CK-MB明显升高,12 h血清CK-MB阳性结果动物数量最多,灵敏度为88.2%,特异度为66.7%,阴性预测值为80%.结论:漂浮导管、超声心动图、心电图均能较早检测出心肌挫伤,而肌钙蛋白Ⅰ和CK-MB则稍晚.漂浮导管检测心肌挫伤的真实性和诊断价值最好,其次为肌钙蛋白Ⅰ和超声心动图对肺动脉估测压差的检测,CK-MB和心电图真实性和诊断价值较差.%Objective: To study the pathophysiology of myocardial contusion, find out the early diadynamic criteria and evaluate their validity and diagnostic value. Methods: Thirty-six healthy rabbits were selected and impacted by self-made impact machine to produce myocardial contusion. The changes of the ECG, echocardiography, floating catheter, troponin Ⅰ , CK-MB were observed respectively at time phases as before and 1,6,12,24,48 hours after wounding. The rabbits wer divided into MC group and non-MC group according to the pathology. Compared the earliest time of the diadynamic criteria and evaluated their validity and diagnostic value. Results: Mter myocardial contusion, most rabbits appeared ST-T changes in ECG at 1 hour. The sensitivity was 58.8％. the specificity was 75％, the negative predictive was 56.2％. The echocardiography appeared changes such as the EF dropped etc at 1 hour. but most rabbits appeared changes at 6 hour. The sensitivity was 93.3％％, the specificity was 78.6％. the negative predictive was 91.7％. Most rabbits' central venous pressure and pulmonary artenal pressure measured by floating catheter raised at 1 hour. The sensitivity was 100％. the specificity was 83.3％, the negative predictive was 100％. Most rabbits' Troponin- Ⅰ raised at 6 hour after myocardial contusion.The sensitivity was 94.1％, the specificity was 100％, the negative predictive was 92.3％. CK-MB raised at 6 hour, and most rabbits' CK-MB raised at 12 hour. The sensitivity was 88.2％, the specificity was 66.7％, the negative predictive was 80％. Conclusion: Floating catheter, echocardiography and ECG can detect myocardial contusion early. Troponin- Ⅰ and CK-MB were later. Floating catheter has the best validity and diagnostic value, followed by troponin- Ⅰ and echocardiography, finally was CK-MB and ECG.