Abstract Funding Acknowledgements Type of funding sources: Public Institution(s). Main funding source(s): NIHR, Evelyn Trust, Burdett Trust. Background Multiple investigations have explored the lived experience of heart failure (HF). However, studies have not interrogated whether differences exist according to HF phenotype and the lived experience of people with Heart Failure with preserved Ejection Fraction (HFpEF) remains unexplored. We hypothesised patients with HFpEF may articulate different experiences from those with other forms of HF, given established problems around awareness, diagnosis and management. Purpose To explore how HFpEF impacts upon patients’ lives and interrogate whether and how known challenges impact upon patient experience. Methods Secondary thematic analysis of interview transcripts from 77 people diagnosed with HFpEF and their carers. The analysis was informed by the Cumulative Complexity Model (CCM). Results Four themes underpinned by the CCM were generated. Theme 1: Shouldering a Heavy Workload, described the many health related tasks (patient work) people living with HFpEF were expected to perform. Theme 2: The Multiple Threats to Capacity described how patients tried to perform this work, however, were frequently hindered by challenges such as difficult to manage symptoms or mobility/age-related conditions. Patient work and ability to perform this work were complicated by problems synthesised under Theme 3: Deficient Illness Identity. This theme illustrated how healthcare providers sometimes perceived HFpEF to be a more benign or untreatable form of HF, which could lead to limited access or lower priority for supportive services. Together, themes one to three contributed to a range of negative outcomes captured within Theme 4: Spiralling Complexity. Conclusions HFpEF, multimorbidity and aging cumulatively create multiple demands that people with HFpEF must attend to, whilst they concurrently negotiate symptoms and physical limitations that make this challenging to achieve. Patient work and patient capacity to perform work are impeded by a system that undermines their candidacy for optimum HF care. Such conditions create unfavourable outcomes that will continue, unless system wide change is implemented.