Longer symptom onset-to-door time persists despite reductions in stemi door-to-balloon time: insights from the Victorian Cardiac Outcomes Registry.

Abstract

Background: Prompt revascularisation is central to achieving optimal outcomes for patients presenting with ST-segment elevation myocardial infarction (STEMI). To enable this, health systems have traditionally focused on the 'door-to-balloon' (DTB) component of total ischaemic time, while comparatively less attention has been given to symptom 'onset-to-door' (OTD) time. Objective(s): To determine the temporal trends, predictors and outcomes among patients with increased OTD time. Method(s): Consecutive patients with STEMI treated with percutaneous coronary intervention (PCI) across 30 hospitals in the Victorian Cardiac Outcomes Registry were analyzed between 2014 and 2020. Linkage with data from Ambulance Victoria was performed for all patients transported via emergency medical services. Trends in OTD and DTB time were evaluated with Cochrane-Armitage test of trend. Characteristics and outcomes of patients with longer OTD time (>60 mins) were compared to those with shorter OTD time (<60 mins). Multivariable predictors of longer OTD were determined with logistic regression and presented as odds ratio and 95%CI in a forest plot. Result(s): A total of 13,494 patients underwent PCI for STEMI with median OTD time of 150mins (86,328) and median DTB time of 66mins (43,107). DTB time progressively reduced over the study period (p=0.001) while the proportion of patients with longer OTD did not change (90.3%, p=0.91). Patients with longer OTD time were more likely to be older (>65yo = 41% vs. 35%, p<0.001), female (22 vs. 16%, p<0.001), live in a lower-socioeconomic area (36 vs. 28%, p<0.001), be treated for diabetes (17 vs. 13%, p<0.001), have developed their symptoms out-of-hours (65 vs. 60%, p=0.002) and present via ambulance [vs. self-present] (81 vs. 63%, p<0.001). Multivariable predictors of longer OTD time are presented in forest plot below. Higher rates of new renal impairment (6.7 vs. 5.0%, p=0.024) and 30-day MI (1.5 vs. 0.7%, p=0.017) were observed among patients with longer OTD, as were numerical trends in new 30-day heart failure (1.4 vs. 0.9%, p=0.22) and in-hospital shock (5.9 vs. 4.7%, p=0.081). Conclusion(s): No change in the proportion of patients presenting with longer onset-to-door times was observed despite a parallel reduction in door-to-balloon time over the study period. Increased community awareness and education on the symptoms of myocardial infarction, particularly targeted at high risk demographic groups, are needed to further reduce ischaemic times.