Usually the heart beats in a regular, organised fashion controlled by a small group of pacemaker cells found on the right side of the heart. It’s also normal for the heart to pump at different rates during the day – for example if we exercise or become anxious.
Arial fibrillation is a condition in which the heart beats irregularly and usually too fast. It is the most prevalent abnormal heart rhythm and is estimated to affect over one million people across the UK. It can occur in adults of any age, but is more common as people get older – being found in one in ten individuals over the age of 65.
People with atrial fibrillation may be aware of an irregular, fast heartbeat. They might also feel tired, breathless, dizzy or faint. But some will only have mild symptoms while others will have no symptoms at all.
The major risk from unrecognised and untreated atrial fibrillation is an increased likelihood of stroke. The abnormal rhythm leads to turbulent blood flow within the heart that can cause a blood clot to form. If this clot then blocks the blood supply to part of the brain a stroke occurs.
Research from Australia published in the latest issue of Thrombosis and Haemostasis demonstrated that screening for atrial fibrillation in people without any symptoms – using an electrocardiogram (ECG) – as part of a full health check or health assessment could be a potent way to prevent strokes. In a study of 5555 patients with previously undetected atrial fibrillation – and no symptoms – matched to 24,705 controls, they found that having atrial fibrillation more than doubled the risk of stroke. Moreover treating such individuals with the blood thinning agent warfarin significantly reduced both their stroke risk and the increased chance of dying from a stroke.
Last month NICE published new guidance on atrial fibrillation. They recommend that people ask their doctor to check their pulse for irregularities if they have any symptoms and for the doctor to then consider arranging an electrocardiogram (ECG). However, based on the research from Australia, it seems that this advice is already out of date.