Early detection of AF could prevent thousands of strokes per year

Dr Husain Shabeeh

Dr Husain Shabeeh is a Consultant Cardiologist and Electrophysiologist, and Clinical Lead for Heart Rhythm on MedShr, the world’s leading case discussion platform for healthcare professionals.

Whether Atrial fibrillation (AF) is causing symptoms or not, the risk of stroke is significant. Dr Shabeeh explores approaches for detection of AF and protection from stroke.

Atrial fibrillation (AF) is a common abnormal heart rhythm, especially with increasing age of the population. It is estimated that it affects almost 2% of the population, with incidence increasing with age, especially over the age of 65. The causes of AF can be related to a variety of reasons including heart disease, lung disease, thyroid dysfunction, as well as lifestyle factors such as increased weight and alcohol intake. Sometimes there is no obvious cause.

In AF, the heart beats irregularly which can cause symptoms such as tiredness, breathlessness and palpitations. However, in many cases AF is symptomless and is found incidentally, for example at a routine pulse check or ECG test. This means that there is a large proportion of patients that may have AF and remain undiagnosed.

AF can occur in bursts (paroxysmal AF) or can be present all the time (persistent AF). There are various medications that are used to control the heart rate which can often be fast, as well as options to control the heart rhythm to maintain normal (sinus) rhythm.

Over 20% of strokes may be due to Atrial fibrillation

The risk of stroke is estimated to be five times greater for those with AF. The chambers of the heart where blood collects are the atrium, and these quiver (fibrillate) and hence do not contract properly. This allows blood to collect which can then form clots, which in turn can break off to the brain causing stroke.

It is thought that over 20% of all strokes are due to AF, and strokes due to AF tend to be worse, with a higher mortality and morbidity.

A large proportion of people with AF remain undiagnosed

Whether AF is causing symptoms or not, the risk of stroke is present. This therefore means that there are a large proportion of people with AF who remain undiagnosed and are at risk of stroke. Early detection of AF is therefore paramount, as it allows for appropriate initiation of anticoagulant therapy (“blood thinners”) to significantly reduce the risk of stroke.

Detecting Atrial fibrillation

Detection of AF may be easier in those who have symptoms, with ECG being the key investigation. It may be that patients have symptoms all the time, but there are those where symptoms come and go. Various devices such as ECG monitors and even personal wearable devices can be used to obtain an ECG at the time of symptoms.

Higher risk groups not displaying symptoms can potentially be screened with pulse checks, ECG and increasing awareness.

Protecting from stroke

Once a diagnosis of AF has been established, patients are assessed for their stroke risk. A large proportion of these are deemed to require initiation of anticoagulant therapy, with a variety of oral anticoagulants available for AF that significantly reduce the risk of stroke. It is felt that identifying AF and then prescribing appropriate anticoagulation could prevent thousands of strokes per year in the UK, in turn saving thousands of lives.

How can doctors identify patients with AF?

A simple pulse check at time of clinical assessment, especially for higher risk groups, could identify those who require further investigations such as an ECG.

Healthcare professionals and medical students are also encouraged to join the Heart Rhythm Case Discussion Group on MedShr to learn from a wide range of heart rhythm cases.

If you are a patient and are concerned about your heart, speak to your doctor