Arrhythmias are also known as heart rhythm problems. Most people with an abnormal heart rhythm can lead a normal life if it is properly diagnosed. The main types of arrhythmia are:
- atrial fibrillation (AF) – this is the most common type, where the heart beats irregularly and faster than normal
- supraventricular tachycardia – episodes of abnormally fast heart rate at rest
- bradycardia – the heart beats more slowly than normal
- heart block – the heart beats more slowly than normal and can cause people to collapse
- ventricular fibrillation – a rare, rapid and disorganised rhythm of heartbeats that rapidly leads to loss of consciousness and sudden death if not treated immediately with a defibrillator
Arrhythmias can affect all age groups, but atrial fibrillation is more common in older people. Drinking alcohol in excess or being overweight increases your likelihood of developing atrial fibrillation. You may also be at risk of developing an arrhythmia if your heart tissue is damaged because of an illness – for example, if you have had a heart attack or have heart failure.
Atrial fibrillation is also a common cause of stroke. Having atrial fibrillation means your risk of stroke is 5 times higher than for someone whose heart rhythm is normal. Certain types of arrhythmia occur in people with severe heart conditions, and can cause sudden cardiac death. Some of these deaths could be avoided if the arrhythmias were diagnosed earlier. Common triggers for an arrhythmia are viral illnesses, alcohol, tobacco, changes in posture, exercise, drinks containing caffeine, certain over-the-counter and prescribed medicines, and illegal recreational drugs.