Impact of time of admission on short- and long-term mortality in the Vienna STEMI registry

Abstract Background Several studies have shown contradictive findings regarding mortality and hospital admission time in patients presenting with ST-elevation myocardial infarction (STEMI). The aim of this study was to assess the impact of "on-" or "off-hour" admission on short- and long-term all-cause mortality of patients in the advanced Vienna STEMI network between 2003 and 2009. Methods and results In total, 2829 patients were included into this analysis. Patients were stratified according to admission time into "on-hour" admission (07:30 until 15:00h on weekdays) and "off-hour" admission (15:00–7:30h on weekdays and 24h on weekends). As endpoint of interest, all-cause mortality was investigated after 30days and 3years of follow-up, the latter for all patients and as Landmark analysis for survivors of the index event. Mean age was 60.5±13.3years, 2048 (72.4%) patients were male and 1260 (44.5%) patients presented with anterior wall infarction. 683 (24.1%) patients were admitted "on-hours", 2146 (75.9%) patients were admitted "off-hours". All-cause death occurred in 176 (6.2%) patients after a follow-up of 30days and in 337 (11.9%) patients after 3years. For short- and long-term all-cause mortality no significant differences could be detected between "on-" and "off-hour" admission in univariate and multivariate Cox proportional hazard analyses as well as for propensity score adjusted outcome analysis. Conclusion In the Vienna STEMI network, "on-" or "off-hour" admission had no impact on short- and long-term mortality for all-comers presenting with acute STEMI. Our findings confirm the imperative need for well-structured STEMI networks of care, as previous data repeatedly demonstrated increased adverse cardiovascular outcome for "off-hour" admission.