Heart failure occurs when the heart is no longer able to pump blood around the body properly. It can cause breathlessness, swollen feet and ankles, and tiredness. In about half of patients with heart failure, one measure of the heart's pumping function, called the 'ejection fraction', is normal. This type of heart failure is called heart failure with preserved ejection fraction, or HFpEF.

HFpEF remains poorly understood. It is not clear why some people develop HFpEF, or what determines the severity of the condition. Treatment options may be limited.

UK HFpEF is a study that aims to gain a better understanding of why people develop HFpEF, develop better tests to diagnosis it, identify and test new treatments, and follow the health of the people taking part over many years.

Approximately half of patients with heart failure have a normal, or preserved, left ventricular ejection fraction (HFpEF) (Owen et al, 2006). Rather than being a single diagnosis, it has become clear that HFpEF represents a heterogeneous syndrome involving a range of pathophysiological mechanisms, clinical factors and outcomes (Lewis et al, 2017). However, to-date, HFpEF has generally been considered as a single disease entity. Several high profile phase III trials in HFpEF have shown potentially impressive efficacy in some subgroups of patients, but failed to prove significance over entire cohorts (Pitt et al, 2014) (Solomon et al, 2019). This is likely due to the 'one-size-fits-all' approach taken, with insufficient stratification of the various underlying disease mechanisms.

The large and rapidly growing burden that HFpEF places on our healthcare systems mean there is a pressing need to better understand HFpEF and improve the management of patients with it. The recurrent lack of benefit of the one-size-fits-all approach mandates a new, personalised approach.

The UK HFpEF registry will be a key platform for collaborative UK clinical and translational HFpEF research. The aim is that multiple centres will collaborate and contribute patients such that the registry will provide deep phenotyping, linked to outcomes, in, ultimately, many thousands of patients. This will enable, for example, machine learning techniques to be applied at scale in order to reclassify HFpEF more powerfully. It will provide a platform for the development of diagnostics specific to the different HFpEF subgroups, and for more effective trials that will target groups of patients in whom new, repurposed or previously discarded treatments are expected to be effective. Moreover, it will provide cohorts of patients readily available for recruitment, with linkage in place for outcomes. It could be used to leverage commercial funding and participation, facilitated by simplified, single-point access for industry. It will enable scaled investigation aimed at understanding causes of HFpEF, improving risk stratification and providing better care.

Inclusion Criteria:

1. Written informed consent
2. Diagnosis of HFpEF by a cardiologist with HF expertise, or a primary care physician with HF expertise, or a heart failure nurse
3. Natriuretic peptide levels measured

Exclusion Criteria:

1. LV EF < 40% (at screening or any previous measurement)
2. Known infiltrative cardiomyopathy (e.g., amyloid, sarcoid, lymphoma, endomyocardial fibrosis)
3. Known active myocarditis, constrictive pericarditis, or cardiac tamponade
4. Known genetic hypertrophic cardiomyopathy or obstructive hypertrophic cardiomyopathy
5. Known arrhythmogenic right ventricular cardiomyopathy
6. Known severe primary valvular heart disease
7. Known idiopathic, heritable or drug-induced pulmonary arterial hypertension
8. Heart transplantation or ventricular assist device
9. Complex congenital heart disease

All individuals will be considered for inclusion in this study regardless of age, disability, gender reassignment, marriage and civil partnership, pregnancy and maternity, race, religion and belief, sex, and sexual orientation, except where the study inclusion and exclusion criteria explicitly state otherwise.

Participants will be asked to provide consent for pseudonymised study data, including, for example, individual patient-level data, scans and any other study data, to be shared for research purposes with investigators or organisations, including independent commercial organisations ('industry'), in the United Kingdom or overseas, including outside of the European Economic Area and in the United States of America. Participant personal details such as name, address, date of birth, will not be shared.

Requests for access to the data will be managed by the Executive Steering Committee. Release of data to investigators or organisations requesting access, whether they reside within or outside the UK, will be covered by a Data Transfer Agreement. The Data Transfer Agreement is a legally binding document that will regulate the use of data to ensure that standards are maintained.

Within the life time of the study

Release of data or samples to investigators or organisations requesting access, whether they reside within or outside the UK, will be covered by Data and/or Material Transfer Agreements. The Agreements are legally binding documents that will regulate the use of data and/or samples to ensure that standards are maintained.