Diastolic Heart Failure (Preserved Ejection Fraction)

Diastolic heart failure, now usually termed heart failure with preserved ejection fraction (HFpEF), is the phenotype in which the left ventricle contracts normally — ejection fraction is preserved (commonly 50% or above) — but fills abnormally because it is stiff and relaxes poorly. The result is elevated filling pressures and congestion despite apparently preserved pump function.

Definition

Heart failure with preserved ejection fraction is a heart failure syndrome in which left ventricular ejection fraction is preserved (typically 50% or above) but there is evidence of diastolic dysfunction or raised filling pressures, so symptoms arise from impaired ventricular filling rather than impaired ejection.

Scope

This topic covers the definition of HFpEF by preserved ejection fraction with evidence of diastolic dysfunction, the mechanisms of impaired relaxation and increased stiffness, its distinctive epidemiology, and how it contrasts with the reduced-ejection-fraction phenotype. It is an educational reference rather than clinical guidance. Note: the canonical MeSH descriptor for this entity is 'Heart Failure, Diastolic' (D054144).

Core questions

• How can heart failure occur when ejection fraction is preserved?
• What does impaired ventricular relaxation and increased stiffness do to filling pressures?
• How is HFpEF diagnosed when systolic function looks normal?
• Why has disease-modifying therapy been harder to establish in HFpEF than in HFrEF?

Key concepts

• Preserved ejection fraction (typically 50% or above)
• Impaired left ventricular relaxation
• Increased ventricular stiffness and elevated filling pressures
• Diastolic dysfunction
• Comorbidity-driven phenotype (hypertension, obesity, ageing)

Mechanisms

In HFpEF the left ventricle ejects a normal fraction of its volume, but its ability to relax and fill at low pressure is impaired by myocardial stiffening, hypertrophy, and fibrosis. As the stiff ventricle requires higher pressures to fill, those pressures are transmitted back to the lungs, producing congestion and exertional breathlessness. The phenotype is closely tied to comorbidities such as hypertension, obesity, diabetes, and ageing, and its mechanistic heterogeneity is one reason disease-modifying therapy has been harder to establish than in the reduced-ejection-fraction phenotype.

Clinical relevance

HFpEF represents a large and growing share of heart failure, particularly in older adults, and recognising that preserved ejection fraction does not exclude heart failure is central to evidence appraisal. This entry describes the phenotype conceptually and is not a basis for individual diagnostic or treatment decisions.

Epidemiology

Epidemiologic reviews indicate that the preserved-ejection-fraction phenotype accounts for a substantial and increasing proportion of heart failure cases, with higher prevalence among older adults, women, and people with hypertension, obesity, and diabetes.

Evidence & guidelines

The 2021 ESC guideline defines HFpEF and frames its diagnostic criteria. More recent randomised trials of sodium-glucose cotransporter-2 inhibitors, such as EMPEROR-Preserved and DELIVER, provided the first consistent trial evidence in this phenotype. These works are cited as reference and classification sources, not as treatment instructions.

History

Heart failure with normal systolic function was long debated as a distinct entity, sometimes dismissed or attributed to measurement issues, before being consolidated as 'diastolic heart failure' and later 'HFpEF'. For years trials failed to show benefit, reinforcing its reputation as a difficult phenotype, until the EMPEROR-Preserved and DELIVER trials of SGLT2 inhibitors demonstrated consistent effects, marking a turning point in its evidence base.

Debates

Is HFpEF a single disease or a heterogeneous syndrome?

Because it is defined largely by exclusion (heart failure with preserved ejection fraction) and is driven by varied comorbidities, many argue HFpEF comprises several distinct phenotypes, which may explain why broad therapeutic strategies historically struggled to show benefit.

Key figures

• Stefan Anker
• Scott Solomon
• Theresa McDonagh

Seminal works

• anker-2021-emperor
• solomon-2022-deliver
• mcdonagh-2021-esc

Frequently asked questions

How can someone have heart failure with a normal ejection fraction?

Ejection fraction measures how well the ventricle empties, not how well it fills. In HFpEF the ventricle ejects normally but is stiff and relaxes poorly, so it can only fill at elevated pressures, which produces congestion and heart-failure symptoms.

How does HFpEF differ from HFrEF?

HFpEF has preserved ejection fraction (typically 50% or above) with impaired filling, whereas HFrEF has reduced ejection fraction (40% or below) from impaired contraction. They differ in mechanism, typical patient profile, and the strength of their trial evidence.