Getting to the heart of atrial fibrillation

What is atrial fibrillation?

Atrial fibrillation (AF) is a common heart rhythm disorder caused by the chaotic contraction of the top chambers of the heart called the atria. Over a million patients live with atrial fibrillation in the UK. It may come and go sporadically (paroxysmal) or it may be there all the time (persistent or permanent). Whilst it is not usually life-threatening, it is important to recognise this condition as it can increase the risk of stroke.

What causes AF?

Episodes can be precipitated by a number of other conditions, including infections, anaemia, alcoholic binges, or an overactive thyroid. However, more often we do not find a cause but AF is associated with increasing age, high blood pressure, diabetes, coronary artery disease, heart valve disease, heart failure, lung conditions, obesity and high alcohol intake. 

What symptoms might I have?

An irregular (often rapid) pulse may be the only sign that you have AF. If you take your blood pressure at home, you may notice your heart rate recordings registering higher than usual. Some patients are completely unaware of symptoms, hence it is important for doctors to screen for AF by taking your pulse. Other patients can experience flutters in the chest (palpitations), dizzy spells, breathlessness, tiredness, chest pains or even pass out.

What investigations are required?

The diagnosis is made by an electrical recording of the heart called an electrocardiogram (ECG). Simple blood tests should exclude reversible causes or precipitants. An ultrasound scan of the heart called an echocardiogram is often performed to exclude heart dysfunction and valve problems. If you are in AF all the time, you may be asked to wear a portable cardiac monitor called a Holter to assess your heart rate over 1-2 days.

What is the risk of stroke?

Stroke risk is dependent on a number of factors including age and the presence of a number of other medical conditions, some of which are mentioned above. The more risk factors, the higher the risk. Your GP can assess your annual risk using a scoring system called CHADSVASc. If indicated, a blood thinner called an anticoagulant is usually recommended to reduce the risk.

What are the treatments for AF?

The majority of patients without symptoms can be left in permanent AF provided their heart rate is controlled, usually with medication. Patients with symptoms can be treated with drugs to restore or maintain a normal rhythm. In persistent cases, a short procedure called DC cardioversion can reset the heart rhythm by passing an electrical pulse across the chest under general anaesthetic. In the most symptomatic cases, an invasive procedure called catheter ablation can be used to improve symptoms by destroying the abnormal areas of the heart causing AF. In much older patients, a pacemaker may be needed to help control symptoms or allow safe administration of medication.

For more information about heart treatments available, click here.

Dr Michael Koa-Wing is a Consultant Cardiologist at Spire Bushey Hospital. 

The content of this article is provided for general information only, and should not be treated as a substitute for the professional medical advice of your doctor or other health care professional.