Impact of structured STEMI program implementation on 1 year outcomes in low middle income country: a propensity score matched cohort study

Background Timely primary percutaneous coronary intervention (PCI) is central to STEMI management. Following the Heart Attack Ethiopia initiative, mission supported efforts enabled establishment of a structured STEMI care program to standardize rapid triage, catheterization laboratory activation, and guideline directed therapy. Purpose To evaluate the impact of STEMI program implementation on 1-year clinical outcomes. Methods we conducted a single center cohort study in 200 participants comparing consecutive STEMI patients treated before program implementation with patients managed after implementation of the program (prospectively followed cohort). Propensity score matching based on age and sex was performed. Baseline characteristics were summarized using means for continuous variables and proportions for categorical variables. The primary endpoint was 1-year major adverse cardiovascular events (MACE: death, reinfarction, stroke, heart failure hospitalization, or unplanned revascularization). Follow up was administratively censored at 365 days. Kaplan Meier analysis and log rank testing were performed. This analysis represents a preliminary report; additional data will be incorporated into the final presentation. Results Seventy-seven patients were included (27 pre-program, 50 post program). Baseline characteristics were broadly comparable. MACE occurred in 6 patients (22.2%) in the pre-program era and 2 patients (4.0%) following program implementation. At 1 year, Kaplan Meier estimated cumulative incidence of MACE was 37.0% in the pre-program cohort versus 4.0% in the structured program cohort (absolute risk reduction 33.0%; log rank p=0.024). The post program era was associated with more consistent primary PCI delivery and improved adherence to guideline directed medical therapy. Conclusions Implementation of a structured STEMI care program supported by the Heart Attack Ethiopia initiative was associated with a significant reduction in 1 year MACE compared with the pre-program era, despite prior erratic PCI availability. These findings suggest that system level organization and protocolized delivery of care confer meaningful outcome benefits in resource constrained settings. Expanded prospective follow up will further define the durability and magnitude of effect.