Abstract: Objective To explore the changes of QRS combined data and myocardial enzymes during ischemia-reperfusion in rabbits,and observe the changes of ST segment and T wave of lead Ⅱ,and arrhythmias.Methods The models of ischemia-reperfusion(A,B,C and D group)were made by ligating the left circumflex territory for 10,20,30,40 min and then reperfusion for 60 min.The sham-operated control was designed.The changes of the QRS combined data,ST segment and T wave and rises of arrhythmias about electrocardiogram of lead Ⅱ were observed.Meanwhile,the activity of serum myocardial enzymes was measured.Results The QRS combined data of the group D was higher significantly than the sham-operated control,group A and group B(P<0.05).T waves of different groups were not significantly different(P>0.05).The J spot elevation of lead Ⅲ in 19 rabbits of the ligating group and 5 rabbits of the sham-operated control was observed before operation.The changes of ST segment were clearly observed in the ligating group after operation:apparent mono-phasic curve elevation in 21 rabbits,level type depression in 2 and no change in 1.ST segment of other animals was declined more than 0.2 mV in 60 min reperfusion,except ST segment of 2 rabbits elevated again more than 0.1 mV,2 rabbits were normal and 1 rabbit was depressed.Two rabbits of the group D respectively died of sinus bradycardia in reperfusion 40 min and 43 min,and two rabbits appeared premature ventricalar contraction during reperfusion 3-5 min.The activity of serum aspartate aminotransferase(AST)and lactate dehydrogenase(LDH)obviously increased in the group D(P<0.05).Creatine kinase(CK)was high significantly except the sham-operated control(P<0.05).The activity of serum CK-MB of the groups C and group D was significantly higher than that of the sham-operated control(P<0.05).Conclusion The rising of LDH,CK-MB and QRS combined date in the group D is related with ischemia-reperfusion injury.

Key words: ischemia-reperfusion, combined data of QRS complex waves of electrocardiogram, myocardial enzyme