BackgroundPatients who experience in-hospital ST-segment elevation myocardial infarction (iSTEMI) represent a uniquely high-risk cohort owing to delays in diagnosis, prolonged time to reperfusion and increased mortality. Quality initiatives aimed at improving the care of this vulnerable, yet understudied population are needed.MethodsThis study included consecutive patients with iSTEMI treated with percutaneous coronary intervention (PCI) between 1 January 2011 and 15 July 2019 at a single, tertiary referral centre. A comprehensive iSTEMI protocol (CSP) was implemented on 15 July 2014, incorporating: (1) cardiology fellow activation of the catheterisation lab using standardised criteria, (2) nursing chest pain protocol, (3) improved electronic access to electrocardiographic studies, (4) checklist for initial triage and management, (5) 24/7/365 catheterisation lab readiness and (6) radial-first PCI approach. Key metrics and clinical outcomes were compared before and after CSP implementation.ResultsAmong 125 total subjects, the post-CSP cohort (n=81) was younger, had more males and were more likely to be hospitalised for cardiac-related reasons relative to the pre-CSP cohort (n=44) who were more likely hospitalised for operative-related aetiologies. After CSP adoption, median ECG-to-first-device-activation time decreased from 113 min to 64 min (p<0.001), goal ECG-to-first-device-activation time increased from 36% to 76% of patients (p<0.001), administration of guideline-directed medical therapy prior to PCI increased from 27.3% to 65.4% (p<0.001), trans-radial access increased from 16% to 70% (p<0.001) and rates of discharge home increased from 56.8% to 76.5% (p=0.04). Statistically insignificant numerical reductions were observed post-CSP in in-hospital mortality (18.2% vs 9.9%, p=0.30), 30-day mortality (15.9% vs 12.3%, p=0.78) and 1-year mortality (27.3% vs 21.0%, p=0.57).ConclusionsThe implementation of a CSP was associated with marked enhancements in key care metrics among patients with iSTEMI. Among a larger cohort, the use of a CSP yielded a significant reduction in ECG-to-first-device-activation time in a particularly vulnerable population at high risk of death.