RESUMO
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.