Does atrial fibrillation cause shortness of breath?

Atrial fibrillation causes the upper chambers of the heart to beat irregularly. The lower chambers may then pump less efficiently, so the body can feel short of oxygen during exertion. You may notice breathlessness, tiredness, reduced exercise tolerance, or awareness of a racing or fluttering heartbeat. Shortness of breath can also have other heart, lung, blood, or anxiety-related causes, so this symptom alone cannot identify atrial fibrillation.

Arrange a medical assessment if breathlessness is new, recurring, or linked with a fast or irregular pulse. A clinician may check your pulse and blood pressure and arrange an electrocardiogram. Keep a note of when symptoms begin, what you were doing, how long they last, and whether they settle with rest. Take prescribed heart medicines as directed and do not change the dose without advice.

Seek emergency help for severe or sudden breathlessness, chest pain or pressure, fainting, confusion, blue or grey lips, or symptoms that do not improve with rest. Sudden weakness, facial drooping, or trouble speaking also needs urgent attention because a heart rhythm problem can be associated with serious complications.

Ask whether your symptoms need an electrocardiogram, how to check your pulse, which warning signs require emergency help, and whether any current medicines or lung conditions could be contributing to your breathing difficulty.