On- Vs. Off-Hours Admission of Patients With St-Elevation Acute Myocardial Infarction Undergoing Percutaneous Coronary Interventions: Data From a Tertiary University Brazilian Hospital

Abstract

Introduction:Early reperfusion therapy is crucial in patients with ST-elevation myocardial infarction (STEMI). Off-hours hospital presentation may increase the time from pain to coronary reperfusion, and it may be responsible for increased cardiovascular outcomes. The aim of this study was to compare the effect of different times of presentation (on-and off-hours) on early mortality and major cardiovascular outcomes in patients with STEMI who underwent primary percutaneous coronary intervention (PCI). Methods:We have included consecutive patients with STEMI who underwent primary PCI between April 2011 and November 2016 in a tertiary university hospital in southern Brazil. Patients were divided into on-and off-hours admission. In-hospital and 30-day outcomes were evaluated. Results:A total of 301 patients (57.4%) were admitted during off-hours, and 223 (42.5%) during on-hours. Baseline characteristics were well balanced between the two groups. Median door-to-balloon time was higher in the off-hours group than in the on-hours group: 75 min (IQR 60-95) vs. 60 min (IQR 50-73.7) respectively (p < 0.001). In-hospital mortality was similar between groups (odds ratio [OR] = 0.56; 95% confidence interval [95%CI] 0.31-1.03; p = 0.06) and at 30-day follow-up (OR = 0.2; 95%CI 0.02-1.72 p = 0.14). In the matched cohort, no difference was found in the rates of in-hospital mortality (OR = 2.0; 95%CI 0.75-5.32; p = 0.16) and 30-day MACE (OR= 0.9; 95%CI 0.49-1.66; p = 0.75). Conclusions:In our center with PCI available 24/7 -without in-house staff -we did not observe any difference in patient characteristics, management, and outcomes, although a significant longer door-to-balloon time was found in patients treated during night shifts. Our results are consistent with those of other trials.

Association of door-to-balloon time and clinical factors with hospital shifts

“…These characteristics are in line with the European and national studies that had larger samples. [15][16][17][18] The median door-to-balloon time observed in this study was within the 90 minutes recommended by international guidelines, 5 with the exception of the procedures performed on weekends. Significant differences were observed in door-to-balloon time in primary PCI conducted during working days when compared to weekends, although there was no difference in door-to-balloon time when comparing day and night shifts or on-hours and off-hours.…”

“…19 There are other data that confirm that the door-to-balloon time of individuals seen off-hours seems significantly longer than the door-to-balloon time of individuals seen on-hours. 17,20 The difference can be explained mainly by two reasons: delay in making diagnosis of STEMI and, consequently, delay in referring the patient to the cath lab, and also the smaller number of employees available at the service during weekends. 19,20 In addition, another reason for delay in treating patients undergoing a primary PCI performed off-hours can be the logistical difficulty in reaching the on-call interventional cardiology service staff.…”

“…26 On the other hand, there are data demonstrating that, despite the longer door-to-balloon time in off-hours groups compared to on-hours groups, mortality does not appear to be different in both groups. 14,17 The higher incidence of cases of readmission for any cause, within 30 days, in patients who underwent primary PCI during the day shift compared to those submitted to primary PCI during the night shift seems to be just the result of chance, since it has no plausible justification. Other cardiovascular outcomes followed up in this study (cardiovascular mortality, stent thrombosis, in-stent restenosis, acute MI, unstable angina, stroke and combined outcomes) did not show a significant association with the shift in which the primary PCI was conducted.…”