Heart failure(HF) is usually a chronic condition (see figure). 

The course of the disease is characterised by periods of deterioration of the clinical condition (acute heart failure (AHF), cardiac decompensation). After correct treatment (recompensation), improvement and stabilisation of the clinical condition may occur. The patient feels much better again, but the heart failure remains underlying: chronic heart failure (CHF). 

Usually, heart failure is diagnosed in an episode of acute heart failure, with or without hospitalisation. Patients with chronic heart failure can gradually or sometimes rapidly progress back to acute heart failure due to various triggering factors.

Acute heart failure (AHF) refers to the rapid or gradual onset of symptoms and/or signs of HF, severe enough for the patient to seek urgent medical attention and usually leading to an unplanned hospital admission.  

In AHF, due to dysfunction of the myocardium and certain triggering factors, the pressure in the left ventricle will start to rise, causing increasing salt (sodium chloride) and water retention via the kidneys.  This causes increasing shortness of breath (due to congestion in the lungs) and signs of excessive water retention (congestion): oedema, pleural fluid, ascites. 

AHF can be a medical emergency with risk of hypoxia, cardiac ischaemia, cardiac arrhythmia and (more rarely) generalised hypoperfusion (cardiogenic shock) and death. 

Patients with AHF need urgent medical evaluation for support and prompt initiation or intensification of treatment, including further diagnostic fine-tuning of heart failure. Prompt, correct diagnosis and treatment are crucial to avoid clinical deterioration (admission to intensive care, mechanical ventilation, resuscitation or death).

AHF is a major cause of hospitalisations in persons older than 65 years and is associated with high mortality and high readmission rates. Mortality during hospitalisation varies between 4% and 10%. One year after hospitalisation for AHF, 25-30% of patients have died. 

AHF may be the first manifestation of a new diagnosis of heart failure or may result from acute decompensation of already known chronic heart failure.

After stabilisation of the clinical status and disappearance of signs of congestion, the patient will usually feel much better. However, underlying myocardial dysfunction remains present with evolution into chronic heart failure (CHF). Depending on the cause of heart failure, after correct treatment of the cause, optimal heart failure therapy and time (months), heart function may return to partial improvement or even complete normalisation (see reversible versus non-reversible causes of heart failure). 

The course of chronic heart failure is dynamic with episodes of clinical stability and episodes of cardiac decompensation. Numerous triggering factors or triggers can disturb this balance and give rise to increases in cardiac pressure and/or fluid retention (cardiac decompensation or AHF), with or without the need for hospitalisation. 

Without proper treatment, the prognosis for patients with heart failure is often poor due to progressive deterioration of cardiac function with episodes of increased dyspnea and fluid retention (cardiac decompensation), arrhythmias and multi-organ deterioration (renal insufficiency, liver cirrhosis and ascites, deconditioning and cardiac cachexia,...). This leads to loss of functionality and quality of life, repeated hospitalisations (with high costs to society) and mortality.

With optimal management, these patients are treated with medication and/or implantable devices. Unlike in acute heart failure, the optimal treatment does differ according to the classification according to LVEF (HFrEF, HFmrEF, HFpEF). An optimal policy aims to: 

• the best possible symptom control, preferably without fluid retention (euvolemia) with stable vital parameters (weight, blood pressure and heart rate). 
• the best possible quality of life. 
• improving prognosis:

• • prevention of progressive heart failure and episodes of cardiac decompensation and hospitalisations. 

• • improving life expectancy with prevention of death from progressive heart failure or sudden death (from cardiac arrhythmias). 

Onset of cardiac decompensation may be manifested by changes in symptoms, weight, blood pressure and/or heart rate. Monitoring these parameters in the home situation and timely detection of changes in these parameters can lead to timely adjustments in therapy, sometimes preventing further deterioration and hospitalisation. This shows the importance of a good, structured and qualitative, chronic follow-up of these patients by the patient and his environment itself, the cardiologist, the general practitioner, home care nurse, pharmacist, physiotherapist,... This care path offers a guideline for this.