Severe heart failure symptoms: what to know

Heart failure means the heart cannot pump or fill as effectively as the body needs. Pressure can build behind the heart, causing breathlessness, cough, or difficulty lying flat. Fluid may collect in the legs, ankles, or abdomen. Reduced circulation can cause fatigue, dizziness, cool skin, or confusion. Symptoms may worsen gradually or change suddenly; a new change from your usual pattern matters even when you already have a diagnosis.

Sit upright if breathing feels difficult, keep a record of changes, and contact your heart-failure team or clinician promptly. Take prescribed medicines exactly as directed and do not add or stop water tablets without advice. Follow your agreed fluid and salt plan. Bring a current medicine list to assessment, including non-prescription pain medicines and supplements, because some can worsen fluid retention or kidney function.

Call emergency services for severe breathlessness at rest, inability to speak comfortably, blue or grey lips, fainting, new confusion, chest pressure, or rapidly worsening symptoms. Urgent review is also needed for a new irregular racing heartbeat, sudden swelling, or a sharp fall in exercise tolerance. Do not drive yourself if you feel faint, confused, or severely short of breath.

Ask which symptoms mark a flare for you, how to adjust treatment safely, when to check kidney function and electrolytes, and who to call outside routine appointments.