What should you know about decompensated heart failure symptoms?

Decompensated heart failure occurs when established [Heart Failure](/conditions/heart-failure/) becomes less controlled. Fluid can collect in the lungs or lower legs, while reduced circulation can leave you unusually tired. You may notice breathlessness during activities that were previously manageable, difficulty lying flat, waking short of breath, a new or worsening [Cough](/symptoms/cough/), or [Swollen Ankles](/symptoms/swollen-ankles/).

Some people also notice a racing or irregular heartbeat, known as [Palpitations](/symptoms/palpitations/), reduced appetite, or a rapid change in body weight caused by fluid. [Fatigue](/symptoms/fatigue/) can have many causes, so the pattern and accompanying symptoms help a clinician judge what is happening. [Atrial Fibrillation](/conditions/atrial-fibrillation/) or high blood pressure may contribute to deterioration, but symptoms alone cannot identify the trigger.

Tell your heart-failure team or seek urgent medical advice when breathlessness, swelling, cough, or tiredness is increasing. Record when the change started and whether it affects sleep, walking, or lying down. Have your medicines available and follow your existing monitoring plan.

Continue prescribed treatment unless a clinician gives different instructions. Do not double a dose, stop a medicine, or make large changes to fluid or salt intake without advice. Sit upright if breathing feels easier that way while arranging help. A [Chronic Disease Review](/treatments/consultations-and-assessment/chronic-disease-review/) can support longer-term review after an acute change has been assessed.

Call emergency services for severe breathlessness at rest, blue or grey lips, fainting, confusion, chest pressure, inability to speak normally because of breathlessness, or symptoms that worsen rapidly. These signs require immediate assessment. Do not wait for a routine appointment or drive yourself when you are severely unwell.

Ask which changes are expected for you, which require same-day advice, and which are emergencies. Clarify how to record symptoms, what to do after a missed dose, and when your treatment and monitoring plan should be reviewed.