Off-hours admission does not impact outcomes in patients undergoing primary percutaneous coronary intervention and with a first medical contact-to-device time within 90 min

Background:It remains unclear whether the outcomes of ST-elevation myocardial infarction(STEMI)patients treated with primary percutaneous coronary intervention(PPCI)during off-hours are as favorable as those treated during on-hours,especially those with a first medical contact-to-device(FMC-to-device)time within 90 min.We aimed to determine whether off-hours admission impacted late outcomes in patients undergoing PPCI and with an FMC-to-device time<90 min.Methods:This multicenter retrospective study included 670 STEMI patients who underwent successful PPCI and had an FMC-to-device time<90 min from 19 chest pain centers in Beijing from January 2018 to December 2018.Patients were divided into on-hours group and off-hours group based on their arrival time.Baseline characteristics,clinical data,and key time intervals during treatment were collected from the Quality Control&Improvement Center of Cardiovascular Intervention of Beijing by the 4tHeart and Brain Green Channel”app.Results:Overall,the median age of the patients was 58.8 years and 19.9%(133/670)were female.Of these,296(44.2%)patients underwent PPCI during on-hours and 374(55.8%)patients underwent PPCI during off-hours.Compared with the on-hours group,the off-hours group had a longer FMC-to-device time and fewer patients with FMC-to-device time<60 min(P<0.05).During the mean follow-up period of 24 months,a total of 64(9.6%)participants experienced a major adverse cardiovascular event(MACE),with 28(9.1%)in the on-hours group and 36(9.6%)in the off-hours group(P>0.05).According to the Cox regression analyses,off-hours admission was not a predictor of 2-year MACEs(P=0.788).Similarly,the Kaplan-Meier curves showed that the risks of a MACE,all-cause death,reinfarction,and target vessel revascularization were not significantly different between the two groups(P>0.05).Conclusions:This real-world,multicenter retrospective study demonstrated that for STEMI patients who underwent PPCI within 90 min,off-hours admission was safe,with no difference in the risk of 2-year MACEs compared with those with on-hours admission.