What is atrial fibrillation
Atrial fibrillation (usually referred to as AF) is an abnormality in the rhythm of the heart (arrhythmia). It involves the upper chambers of the heart, the atria, beating irregularly. As the atria control the normal (sinus) rhythm of the heart this means that your pulse becomes irregular. AF is the most common form of arrhythmia, affecting four out of every 100 people over the age of 65.
AF can increase the risk of stroke, the irregular heart rhythm causes the blood to pool and this may cause a blood clot to form which can then be carried to the small blood vessels in the brain where it blocks the blood flow and causes a stroke. To reduce the risk of stroke your doctor will assess your risk factors and decide whether to start you on an aspirin or a blood thinning medication such as Warfarin.
There are many different causes of AF. These include lung disease such as chronic bronchitis and pneumonia, disease of the heart valves, high blood pressure, heart failure, an over active thyroid gland or too much alcohol. However these are not the only causes, and for some there may appear to be no obvious reason.
For some patients, when they have developed AF, they may spontaneously return to normal (sinus) rhythm after a short period of time. However, others may find they alternate between these two rhythms. This is called paroxysmal AF.
A patient may not feel any symptoms when the heart rate changes from normal sinus rhythm to AF, and so it is often only detected by your doctor when you attend for other reasons. However, some patients may present with palpitations (being able to feel the increased heart rate), shortness of breath or chest pains.
There are various ways to treat AF and these can be summarised in to two groups.
Some patients will require rate controlling therapy. This is using medical treatments to slow the speed of the pulse. For this the doctor may prescribe a betablocker (such as bisoprolol), or a calcium channel blocker (such as diltiazem) or digoxin.
Some patients will require rhythm control and attempts may be made to return the heart to sinus rhythm. This technique is called Cardioversion and may be accomplished using medicine therapy such as amiodarone, flecainide or betablockers. Alternatively this may be attempted using an electrical current under general anaesthetic.