肌钙蛋白对急性重度心肌挫伤的早期诊断价值

Early diagnostic efficiency of cardiac troponin for acute severe myocardial contusion

目的 探讨肌钙蛋白对犬重度心肌挫伤早期诊断的价值. 方法 选用12只犬,体重（11.4±1.5）kg.采用BIM-Ⅱ型水平撞击机撞击犬胸前区,制作重度心肌挫伤模型,观察犬伤前、伤后即刻及伤后2,4,6,8h心电图变化.分离向清测定肌钙蛋白T（cTnT）和cTnI的水平,并观察心肌大体和病理氯化三苯基四氯唑（TTC）染色变化. 结果 心电图显示伤后2,4,6,8h出现室上性、室性心动过速、室性早搏、心肌缺血、房颤、室颤等各种心律失常,心电图诊断心肌挫伤的敏感度高但特异度低.伤后2,4 h血清cTnT和cTnI水平与伤前比较无特异度改变,伤后8 hcTnT和cTnI分别达到（0.130±0.052） ng/ml和（1.615±0.371） ng/ml,均较伤前显著升高（P＜0.01）.TTC染色的特异度为（39.78±9.07）％,而血清cTnT和cTnl的敏感度和特异度均为100％. 结论 肌钙蛋白早期诊断重度心肌挫伤的敏感度和特异度高,且与病理相关性好,具有很好的临床应用潜力.

Objective To detemine the value of cardiac troponin in early diagnosis of severe myocardial contusion in the dog.Methods Twelve dogs weighing （11.4 ± 1.5） kg were subjected to severe myocardial contusion by impacting the chest area with BIM-Ⅱ biological impact machine.Electrocardiogram,cTnT and cTnI were measured before,immediately,and 2,4,6 and 8 hours after injury.Animals were then killed and the serum was separated for gross examination and triphenyl tetrazolium chloride （TTC） staining.Results Supraventricular tachycardia,ventricular tachycardia,ventricular premature beat,myocardial ischemia,atrial fibrillation,and ventricular fibrillation were seen on the electrocardiogram 2,4,6 and 8 hours after the injury,which suggested a high sensitivity but low specificity.cTnT and cTnI levels revealed no specific changes at postoperative 2 and 4 hours,but cTnT and cTnl were significantly increased to （0.130 ± 0.052） ng/ml and （1.615 ± 0.371） ng/ml at postoperative 8 hours,significantly higher than that immediately after operation （P 〈 0.01）.Sensitivity and specificity of cTnT and cTnI were both 100%,while the specificity of the TTC staining was （39.78 ± 9.07）%.Conclusion Cardiac troponin is of high sensitivity and specificity in early diagnosis of severe myocardial contusion and has good correlation with pathological changes,which exhibits great potential in clinical application.