BACKGROUND: Patients with heart failure with preserved ejection fraction (HFpEF) are a complex and underserved group. They are commonly older patients with multiple comorbidities, who rely on multiple healthcare services. Regional variation in services and resourcing has been highlighted as a problem in heart failure care, with few teams bridging the interface between the community and secondary care. These reports conflict with policy goals to improve coordination of care and dissolve boundaries between specialist services and the community. AIM: To explore how care is coordinated for patients with HFpEF, with a focus on the interface between primary care and specialist services in England. METHODS: We applied systems thinking methodology to examine the relationship between work-as-imagined and work-as-done for coordination of care for patients with HFpEF. We analysed clinical guidelines in conjunction with a secondary applied thematic analysis of semistructured interviews with healthcare professionals caring for patients with HFpEF including general practitioners, specialist nurses and cardiologists and patients with HFpEF themselves (n=41). Systems Thinking for Everyday Work principles provided a sensitising theoretical framework to facilitate a deeper understanding of how these data illustrate a complex health system and where opportunities for improvement interventions may lie. RESULTS: Three themes (working with complexity, information transfer and working relationships) were identified to explain variability between work-as-imagined and work-as-done. Participants raised educational needs, challenging work conditions, issues with information transfer systems and organisational structures poorly aligned with patient needs. CONCLUSIONS: There are multiple challenges that affect coordination of care for patients with HFpEF. Findings from this study illuminate the complexity in coordination of care practices and have implications for future interventional work.