Atrial Fibrillation

Atrial Fibrillation is a common electrical abnormality of the heart. In stead of being controlled by its own pacemaker, hundreds of cells at the top of the heart become pacemakers, sending multiple signal to the heart making it contract in a rapid and irregular fashion.

Without proper treatment atrial fibrillation is a serious condition and can cause strokes as well as a heart failure.

What causes atrial fibrillation?

Atrial fibrillation is more common in people with underlying heart conditions, but can happen in those with an otherwise normal heart. It can also be triggered by non-cardiac causes such as an overactive thyroid gland or lung conditions.

What are the symptoms of atrial fibrillation?

In 10% of people it has no symptoms, but in the rest palpitations, fatigue and breathlessness can occur.

How can atrial fibrillation be diagnosed?

Atrial fibrillation may be suspected by the symptoms and the finding of an irregular pulse, but it requires an ECG to be sure that it is atrial fibrillation.

Other common tests performed in atrial fibrillation are chest x-ray, blood tests including thyroid function tests and an echocardiogram.

How is atrial fibrillation treated?

Treatment depends to some extent on symptoms and the options are:

  • control of the heart rate (where the atrial fibrillation persists but the heart rate is kept down to prevent the heart from tiring). Heart rate may be controlled by drugs such as beta-blockers, calcium antagonists or digoxin.
     
  • cardioversion where the heart rhythm is changed back to normal rhythm
     
  • ablation where the lining of the heart is cauterised to try and get rid of the atrial fibrillation

Another very important consideration in atrial fibrillation is the risk of strokes caused by lots forming in the heart and then flying off through the circulation to the brain. Your doctors will need to assess this risk, and if there is significant risk warfarin will be prescribed.

What is warfarin?

Warfarin is an anticoagulant, which means it increases the time it takes for the blood to clot and can prevent the formation of potentially harmful clots in the circulation. It is taken in tablet form. The blood-thinning effect of warfarin needs to be monitored closely as too much warfarin can cause bleeding and too little may not prevent the formation of blood clots. The warfarin dose will vary according to the blood test (INR) results; this is usually in the range of 2 - 3 but may vary and will be assessed by your doctor.

It is important to be aware that many drugs, whether prescribed, bought over-the counter or herbal remedies may affect your warfarin and should only be taken under medical supervision. Always tell a pharmacist or doctor that you are on warfarin before starting new medication.

Alcohol is allowed but should only be drunk in moderation. Marked changes in consumption can be dangerous. Warfarin should be taken at the same time each day, preferably in the evening before a meal.

The most common side effects of warfarin are bruising and minor bleeding. To lower the risk of these side effects, your INR should be monitored regularly and kept within the range that is right for you. If you have abnormal bleeding see a doctor immediately.

Please note:

Every effort has been made to ensure that the information on this website is up-to-date and accurate. However, it is intended to serve as a guide only. Symptoms may vary and if you have any medical concerns you should always consult a healthcare professional.