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.

DF and IAW have received consultant fees from the World Health Organization. IAW and LFA have received consultant fees from the Pan American Health Organization. MDH has pending patents for heart failure polypills, has received travel support from the World Heart Federation, and has consulted for PwC Switzerland. George Health Enterprises Pty Ltd and its subsidiary, George Medicines Pty Ltd, have received investment funds to develop fixed-dose combination products, including combinations of blood pressure-lowering drugs; George Health Enterprises Pty Ltd is the social enterprise arm of The George Institute for Global Health.

https://clinicaltrials.gov/study/NCT06080451

Funding support for this study is provided by the U.S. National Institutes of Health (award numbers K23HL161271 and T32GM140935) and the University of Michigan Caswell Diabetes Institute. The funders were not involved in the conceptualization, design, data collection, analysis, decision to publish, or preparation of the manuscript. The content is solely the responsibility of the authors and does not necessarily represent the official views of the funders.

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

This research was approved by the ethics committees of the Ministry of Health of Guatemala (07-2023), the Institute of Nutrition of Central America and Panama (CIE-REV 124/2023), and the University of Michigan (HUM00234613).

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Statistical code, data dictionaries, and training materials from the pilot trial are publicly available on the Harvard Dataverse (https://doi.org/10.7910/DVN/0X8QKE). Certain quantitative datasets will be made available upon reasonable request to the authors; however, some datasets include Ministry of Health administrative data that cannot be shared. Due to participant privacy concerns and risk of re-identification, we do not plan to share qualitative data such as audio recordings or transcripts.