Why does heart failure cause cough?

When the heart does not pump blood forward effectively, pressure can build in blood vessels serving the lungs. Fluid may then move into lung tissue, making breathing less comfortable and triggering a dry or wet cough. Cough is a common presentation of Heart Failure, but cough also has many other causes, including infections, asthma, reflux and smoking.

A cough related to fluid congestion may be more noticeable when lying flat or may interrupt sleep. It can occur alongside breathlessness, reduced exercise tolerance, ankle swelling, or a feeling of needing extra pillows at night.

If you have heart failure and a cough is new, worsening, or different from your usual cough, contact the clinician who manages your heart care. Keep a brief note of when it occurs, whether lying down affects it, and any accompanying swelling or breathlessness. Take prescribed medicines as directed; do not change a diuretic or stop a heart medicine without clinical advice.

If a respiratory infection seems possible, mention fever, mucus changes, sore throat, or contact with unwell people so the cause can be assessed properly.

Seek urgent medical care for severe or rapidly worsening breathlessness, chest pain, fainting, blue or grey lips, confusion, or coughing up pink frothy fluid. Arrange prompt assessment if your cough is persistently worsening, wakes you repeatedly, or comes with new leg swelling or a clear decline in usual activity.

Could this cough be from fluid congestion, a lung problem, or a medicine? Do I need an examination, blood tests, a chest test, or a change to my treatment plan? What changes should prompt me to seek urgent help?