Objective:To assess the changes of cardiac autonomic nervous function at 10 days and 3 months in patients after acute myocardial infarction(AMI) by heart rate variability(HRV) and heart rate turbulence(HRT).In parallel

we examined whether the changes in cardiac autonomic nervous function correlated with coronary revascularization and the expression of Gi2.Methods:64 postinfarction patients without severe complications were enrolled.According to whether successful reperfusion was received

they were divided into two groups(coronary revascularization group and non-coronary revascularization group).24-hour

three-lead ambulatory electrocardiography were performed in all subjects for the analysis of HRV(SDNN and HF/TF) and HRT(TO and TS) at 10 days and three months after acute myocardial infarction.The expression of Gi2 was assessed by Western blot analysis of lymphocytes from patients at the two time points.Results:The fraction of HF/TF and SDNN increased and TO decreased at the time point of three months after AMI in both two groups compared to the time point of 10 days after AMI.TS also increased in non-coronary revascularization group but there was no significant difference between the two time points in coronary revascularization group.There were no significant differences in the parameters(SDNN>100 ms

TO<0

TS>2.5 ms/RR) at 3 months after AMI between two groups.At 10 days after AMI

there was a significant difference in TS between two groups

but there was no significant difference in the SDNN>100 ms and the TO<0.The changes of the Gi2 protein expression were only associated with the changes of SDNN(r= 0.448

P=0.017).Conclusion: There are dynamic changes of HRT and HRV in patients after AMI.The improvement of HRT after successful reperfusion might reflect rapid restoration of baroreceptor sensitivity

but there is no impact on HRV.The hypothesis that Gi2 could serve as molecular marker of cardiac vagal efferent activity could not be supported by the study.