Can atrial fibrillation cause heart failure?

Atrial fibrillation disrupts the heart’s coordinated rhythm. When the ventricles respond too quickly for a prolonged period, the heart may have less time to fill and pump efficiently. Ongoing strain can worsen symptoms such as tiredness, breathlessness and ankle swelling. Heart failure can also stretch or overload the heart, making atrial fibrillation more likely, so the relationship can run in both directions. Other contributors include high blood pressure, valve disease, coronary disease and thyroid problems.

Arrange review if you have palpitations, reduced exercise tolerance, breathlessness when lying down or swelling. Assessment may include an examination, an electrocardiogram, blood tests and heart imaging. Treatment can involve rhythm or rate control, medicines that reduce clot risk when indicated, and management of conditions such as high blood pressure. Take medicines consistently and report worsening breathlessness or rapid weight change rather than adjusting doses yourself. See [Atrial Fibrillation](/conditions/atrial-fibrillation/) and [Heart Failure](/conditions/heart-failure/) for broader explanations.

Call emergency services for chest pain, severe breathlessness, fainting, new confusion or sudden weakness. Seek prompt medical advice for a persistent racing heartbeat, rapidly increasing swelling, breathlessness at rest or symptoms that are worsening despite your usual plan. Early review can identify a rhythm problem or fluid build-up before it becomes more severe.

Ask whether your symptoms suggest a rhythm or pumping problem, which tests are needed, whether clot-prevention treatment is appropriate, and what changes should trigger same-day advice.