Understanding implementation of HEARTS for hypertension and diabetes in Guatemala: qualitative and mixed-methods pilot results

Objectives: Most countries in Latin America have committed to adopting HEARTS, PAHO's recommended approach for managing hypertension and diabetes in national primary care health systems. This study aimed to understand and refine a HEARTS pilot for scale-up in Guatemala. Methods: Team members conducted semi-structured interviews with 30 patients and health workers participating in a HEARTS pilot across 10 primary care facilities in Guatemala's Ministry of Health system. Researchers analyzed interviews using a combined inductive-deductive approach alongside the Tailored Implementation in Chronic Diseases framework and used convergent mixed methods to generate meta-inferences. Results: Despite high feasibility and acceptability scores, health workers described tensions between HEARTS and competing responsibilities. Patients described rational navigation of an unreliable system, a more fitting explanation for low retention than noncompliance. Both patients and health workers understood HEARTS as another externally funded project with uncertain sustainability. Medication availability improved during the pilot, but district and facility-level incentive structures perpetuated supply unreliability. Greater absolute treatment gains for hypertension than for diabetes likely reflected health worker comfort and preexisting access to blood pressure monitoring supplies. Both patients and health workers identified education gaps. Integration of qualitative and quantitative findings suggested concrete scale-up refinements, including simplifying treatment protocols, strengthening diabetes components, focusing training on nurses, reforming central-level pharmaceutical supply policies, and securing high-level Ministry of Health commitments. Conclusions: A HEARTS pilot trial in Guatemala met pre-specified quantitative outcomes, but qualitative and mixed-methods approaches revealed key barriers. These findings will assist in refining HEARTS in Guatemala for planned national scale-up. Trial registration: ClinicalTrials.gov (NCT06080451).