What heart failure means
Heart failure is a clinical syndrome caused by abnormalities of the heart’s structure or function. Raised filling pressures, insufficient blood flow or both may produce breathlessness, fatigue, reduced exercise capacity and swollen ankles. The term does not mean that the heart has stopped beating. These symptoms also occur in other conditions, so medical assessment is essential.
Causes and associated conditions
Coronary artery disease, high blood pressure, valve disease, cardiomyopathies and certain arrhythmias can lead to heart failure. Diabetes, kidney disease and obesity influence both its course and treatment. Identifying the underlying cause can reveal opportunities for targeted treatment.
Ejection fraction: an important update
Echocardiography examines cardiac structure, valves and function. A preserved ejection fraction does not exclude heart failure. The 2026 ESC guideline now distinguishes reduced ejection fraction below 50% from preserved ejection fraction of 50% or higher; the previous “mildly reduced” category is no longer separate. Treatment still depends on the complete clinical picture, rather than a single measurement.1
How the diagnosis is established
The assessment brings together symptoms, examination, an ECG, echocardiography and laboratory tests. BNP or NT-proBNP can help evaluate suspected heart failure; interpretation depends on age, kidney function, obesity, atrial fibrillation and the circumstances of the test. No single symptom or blood result establishes the diagnosis in every patient.
Treatment and prevention
Medicines are selected according to the heart failure phenotype, blood pressure, kidney function and potassium level. Depending on individual indications, treatment may include medicines acting on the renin–angiotensin system, appropriate beta blockers, mineralocorticoid receptor antagonists and SGLT2 inhibitors. Diuretics relieve fluid congestion. Monitoring is needed to balance benefits and adverse effects; do not start or change medicines without your clinical team.
The 2026 framework also emphasises prevention and early recognition, from people at risk to those with advanced disease. Recommendations for several treatments have changed, including a wider role for mineralocorticoid receptor antagonists. Devices, valve procedures and advanced therapies remain options for selected patients.1
Living with heart failure
Follow the agreed treatment plan and keep track of breathlessness, swelling and weight. A rapid weight increase can indicate fluid retention, but your care team should explain what changes require contact and whether you have an agreed diuretic adjustment plan. Appropriate activity and rehabilitation can support daily function. Dietary and fluid advice should be personalised.2
Related cardiovascular guides
Explore cardiac arrhythmias, coronary artery disease and metabolic syndrome and cardiovascular–kidney–metabolic health.
About Massimo Fioranelli · Cardiology and internal medicine · Clinical practice at Sanatrix, Rome
References and further reading
- ESC: 2026 heart failure guidelines; official explanation of the 2026 changes.
- Heart Failure Matters: ESC patient information.
Reviewed 23 October 2026. Educational information does not replace individual medical assessment.