Acute Myocardial Infarction and Primary Percutaneous Coronary Intervention at Night Time

Abstract Background: Primary percutaneous coronary intervention is the preferred treatment in ST-elevation myocardial infarction. At night period, the delay until performing primary percutaneous coronary intervention may be determinant to prognosis worsening. Objective: To analyze the results of primary percutaneous coronary intervention performed at day and night periods. Methods: Cohort study that included patients admitted with ST-elevation myocardial infarction who underwent primary percutaneous coronary intervention from December 2013 until December 2016 in a ST-elevation myocardial infarction reference hospital of a metropolitan region in Brazil, followed from admission to hospital discharge or death, compared according to time of primary percutaneous coronary intervention (night or day). Statistical analysis comprehended the Chi-square test, the Fisher test, the Student's t-test and the analysis of variance, with significance level of 5%. Results: 446 patients were submitted to primary percutaneous coronary intervention, 159 (35.6%) at night time and 287 (64.4%) at day time. No differences were found between the two groups concerning clinical baseline characteristics. Door-to-balloon time (101 ± 81 minutes vs. 99 ± 78 minutes; p = 0,59) and onset-to-ballon time (294 ± 158 minutes vs. 278 ± 174 minutes; p = 0,32) did not differ between the groups. The incidence of combined major adverse cardiac events (15.1% vs. 14.3%; p = 0,58) and in-hospital mortality (9.4% vs. 8.0%; p = 0,61) were similar between the groups, as well as length of hospital stay (6.0 ± 4 days vs. 4.9 ± 4 days; p = 0,91). Conclusion: Primary percutaneous coronary intervention at night time showed similar results as the procedure performed at day time, without significant increase of in-hospital adverse events, length of stay or mortality.