Prof. Rónán Collins
Consultant Physician in geriatric and stroke medicine, Tallaght University Hospital
Clinical lead of national stroke programme and co-chair of Stroke Prevention and Atrial Fibrillation Ireland (SPAFI)
Why is atrial fibrillation important?
Atrial fibrillation (AF) is the most common abnormality of cardiac rhythm, affecting at least 3% of Irish adults over 60, and 6% over 70 years of age. The risk of developing AF is very much associated with age and the worldwide prevalence of AF has been rising. AF is a common condition of ageing.
Symptoms occur in less than half of those affected with AF, so you may not even know you have it. Some common symptoms of AF can be specific like palpitations (awareness of an excessively fast heartbeat) and shortness of breath/chest discomfort. Or, they may be less specific, more general symptoms such as dizziness, tiredness or feeling less energetic. However, AF may be completely silent until disaster strikes and a clot forms in the heart and travels to the brain, causing a stroke.
How is AF diagnosed?
AF is diagnosed by an electric tracing of the heart called an ECG. AF is often picked up and can be suspected if your pulse is irregular. This can be done by self-examination, visit www.irishheart.ie, which can show you how to do this. Your family doctor will check your pulse routinely if you are older or at risk of AF, and arrange an ECG if your pulse seems irregular. Many wearable applications (e.g ‘Apple Watch’). have cardiac monitoring capability that may alert the wearer to the possibility of AF, but the condition needs a reliable tracing to diagnose AF as other conditions may also cause an irregular pulse.
What causes AF and can I reduce my risk of developing AF?
AF is often an age-related phenomenon and there may be an increased risk or tendency to develop AF within families. Sometimes, AF is provoked by a serious infection such as a pneumonia, or toxic causes such as alcohol withdrawal and may resolve with treatment of the condition. In many cases, AF is paroxysmal or ‘intermittent’ and comes and goes, though the risk of stroke may be equally high even where the condition is intermittent.
High blood pressure, being overweight and overuse of alcohol are important, modifiable risk factors associated with the development of AF. Sometimes, a person may have an underlying cardiac condition, like a damaged heart valve, causing AF at a younger age. Occasionally, AF can be associated with other medical problems, like an overactive thyroid or underlying cancer. There is some evidence emerging that excessive and continuous strenuous exercise, for example doing repeated, vigorous endurance training may also predispose people to developing AF.
Knowing and ensuring your blood pressure is normal, reducing your alcohol intake and keeping your weight within healthy range can all help reduce your risk of developing AF in later life.
Can an AF stroke be treated?
Stroke due to AF can be treated, although it is often difficult as the clot blocking the blood vessel may be large or, alternatively, the clot may break up and go down several different smaller blood vessels at the same time, affecting multiple areas of the brain. The key to reducing the effect of an AF related stroke is speed. Once a stroke is suspected by sudden onset of Facial weakness (F), Arm or leg weakness (A), difficulty with Speech (S) then the Time (T) to act is now and ring 999 – FAST. Sudden loss of vision is another warning sign.
Reduce your risk of AF:
• Check and ensure your blood pressure is normal
• Avoid being overweight
• Avoid excessive alcohol