The Circadian Variation Of Acute Myocardial Infarction And The Morning-onset Acute Myocardial Infarction's Impact On 12-month Prognosis

Objective:To investigate the circadian variation of AMI in Chinese and its impact on 12-Month prognosis.Methods:A total of 467 patients diagnosed as AMI who visited China-Japan Union Hospital of Jilin University between January 1st 2015 and October25 th 2016 was retrospectively analyzed in this study.Patients were divided into 2 groups according to whether or not they had a morning onset of AMI,defined as onset between 06:00 and 11:59 hours.The main outcome measures were recurrence of acute coronary syndrome(ACS),re-hospitalization caused by heart failure,major adverse cardiac events(MACE),the all-cause death and the result of coronary angiography during the follow-up period.Results:1.A morning peak was found between 06:00-07:59 based on 2-hour intervals,and 06:00-11:59 based on 6-hour intervals.2.Morning-onset AMI group had lower BMI(p=0.043),shorter Door-to-balloon time(Dto B)(p=0.034),a lower rates of smoker(p=0.002)than the other-time onset group.There were no other significant differences between the 2 groups in terms of other characteristics.3.The incidence of death and heart failure during hospital were similar between the 2 groups.4.Compared with the patients with other-time onset,the morning-onset AMI group showed a significantly higher cumulative risk of rehospitalization caused by heart failure(53.5%vs.39.3%,P=0.032),MACE(76.3%vs.50.3%,P=0.041)within 12-month after discharge.There were no differences in cumulative risk of recurrent ACS and allcause death(P=0.978;P=0.884).On multivariate Cox regression analysis,morning onset was an independent predictor of re-hospitalization caused by heart failure with adjusted hazard ratios of 6.458(95% CI: 2.015-20.697,P=0.002),but not for MACE.5.The morning-onset AMI group showed a significantly higher cumulative risk of non-target vessel revascularization(NON-TVR)(29.3% vs.11.1%,P=0.019)within 12-month after discharge.On multivariate Cox regression analysis,morning onset was NOT an independent predictor of NON-TVR.Conclusion:Compared with other time-onset AMI,the morning-onset AMI showed a significantly higher cumulative risk of re-hospitalization caused by heart failure and MACE,and higher incidence of NON-TVR within 12-month after discharge,needs more attention.