Tailoring implementation strategies for acute coronary syndrome quality improvement program at primary care level in east, west, and central China.

Acute coronary syndrome (ACS) remains a leading contributor to cardiovascular disease burden in China, and ST-segment elevation myocardial infarction (STEMI) is the most severe ACS. To improve early identification and timely treatment of STEMI patients, the chest pain unit (CPU) program was established to strengthen referral pathways to qualified facilities. This study explores key barriers and facilitators to the CPU implementation and proposes context-specific strategies to optimize its delivery and scale-up. We conducted a qualitative study using semi-structured interviews in three purposively selected, representative counties across eastern, central, and western China. A total of 61 key informants from 36 township hospitals participated in the study. All interviews were audio-recorded, transcribed verbatim, and thematically coded guided by the Consolidated Framework for Implementation Research (CFIR) 2.0 using Atlas.ti 9. Implementation strategies were mapped and refined using Expert Recommendations for Implementing Change. We identified 46 barriers and 50 facilitators, spanning all five domains of CFIR. Technical deficiencies, residents' lack of health-seeking awareness, financial difficulties, inefficient awareness campaign, and limited professional knowledge are respectively the most significant barriers for the five domains. We developed a three-pronged strategy framework, including innovation optimization, external empowerment, and internal improvement, to inform future practice. Accordingly, the most urgent strategies encompass enhancing technical capacity, expanding financing mechanisms, empowering communities, implementing mass media campaigns, strengthening patient adherence through structured follow-up, and providing continuous practical training. We recommend that the proposed strategies should be taken into full consideration to facilitate timely detection and intervention of ACS in the primary healthcare context.