Long-Term Implementation and Effectiveness of a Quality Improvement Intervention for Myocardial Infarction in Tanzania.

Background

In Tanzania, acute myocardial infarction (AMI) is underdiagnosed, and uptake of evidence-based care remains limited. The Multicomponent Intervention to Improve Myocardial Infarction Care in Tanzania (MIMIC) increased evidence-based AMI care in a pilot trial conducted in a Tanzanian emergency department (ED). Whether MIMIC was sustained as implemented and its gains persisted after the pilot is unknown.

Objectives

To evaluate the long-term fidelity, penetration, and effectiveness of MIMIC one year after the pilot trial.

Methods

We conducted a sequential cohort study in a Tanzanian ED, enrolling adults with chest pain or dyspnea during the pilot period (September 2023-August 2024) and post-pilot period (September 2024-August 2025). Pre-intervention data (February-August 2023) served as supplemental baseline. Outcomes included fidelity and penetration of MIMIC components and 11 AMI care metrics. Proportions were compared using Pearson's χ² tests and odds ratios (ORs) with 95% confidence intervals (CIs). Findings: Of 260 post-pilot participants, 29 had AMI. Fidelity and penetration of MIMIC components were similar to pilot levels. Electrocardiogram (ECG) uptake remained high (~90% in both periods). Cardiac biomarker testing was lower post-pilot (64.0% [n = 203, excluding stock-out periods] vs 78.0%, OR 0.50, 95% CI 0.35-0.72; P < 0.001), coinciding with reagent stock-outs, but exceeding pre-intervention baseline (41.4%). Among AMI participants, treatment with aspirin, clopidogrel, heparin, and statins in the ED was comparable between pilot and post-pilot periods. Compared with the pre-intervention baseline, uptake of diagnostic testing and evidence-based therapies was substantially higher, including a >5-fold increase in 30-day antiplatelet use (10% vs 52%; OR 9.54, 95% CI 2.49-46.46; P < 0.001).

Conclusions

One year after implementation, MIMIC demonstrated sustained fidelity, penetration, and clinical effectiveness. AMI care remained substantially improved compared with pre-intervention baseline, suggesting that a pragmatic, workflow-integrated intervention can achieve durable gains in AMI care in a resource-limited ED.