Medicines to control atrial fibrillation
Medicines called anti-arrhythmics can control atrial fibrillation by:
- restoring a normal heart rhythm
- controlling the rate at which the heart beats
The choice of anti-arrhythmic medicine depends on the type of atrial fibrillation, any other medical conditions you have, side effects of the medicine chosen, and how well the atrial fibrillation responds.
Some people with atrial fibrillation may need more than one anti-arrhythmic medicine to control it.
Restoring a normal heart rhythm
A variety of medicines are available to restore normal heart rhythm, including:
- beta blockers, particularly sotalol
An alternative medicine may be recommended if a particular medicine does not work or the side effects are troublesome.
Newer medicines are in development, but are not widely available yet.
Controlling the rate of the heartbeat
The aim is to reduce the resting heart rate to under 90 beats per minute, although in some people the target is under 110 beats per minute.
A beta blocker, such as bisoprolol or atenolol, or a calcium channel blocker, such as verapamil or diltiazem, will be prescribed.
A medicine called digoxin may be added to help control the heart rate further.
Normally, only one medicine will be tried before catheter ablation is considered.
As with any medicine, anti-arrhythmics can cause side effects.
The most common side effects of anti-arrhythmics are:
- beta blockers – tiredness, cold hands and feet, low blood pressure, nightmares and impotence
- flecainide – nausea, vomiting and heart rhythm disorders
- verapamil – constipation, low blood pressure, ankle swelling and heart failure
Read the patient information leaflet that comes with the medicine for more details.
Medicines to reduce the risk of a stroke
The way the heart beats in atrial fibrillation means there's a risk of blood clots forming in the heart chambers.
If these enter the bloodstream, they can cause a stroke.
Your doctor will assess your risk and try to minimise your chance of having a stroke.
They'll consider your age and whether you have a history of any of the following:
- stroke or blood clots
- heart valve problems
- heart failure
- high blood pressure (hypertension)
- heart disease
You may be given medicine according to your risk of having a stroke.
Depending on your level of risk, you may be prescribed warfarin or a newer type of anticoagulant, such as dabigatran, rivaroxaban, apixaban or edoxaban.
If you're prescribed an anticoagulant, your risk of bleeding will be assessed both before you start the medicine and while you're taking it.
Aspirin is not recommended to prevent strokes caused by atrial fibrillation.
People with atrial fibrillation who have a high or moderate risk of having a stroke are usually prescribed warfarin, unless there's a reason they cannot take it.
Warfarin is an anticoagulant, which means it stops the blood clotting.
There's an increased risk of bleeding in people who take warfarin, but this small risk is usually outweighed by the benefits of preventing a stroke.
It's important to take warfarin as directed by your doctor. If you're prescribed warfarin, you need to have regular blood tests and, after these, your dose may be changed.
Many medicines can interact with warfarin and cause serious problems, so check that any new medicines you're prescribed are safe to take with warfarin.
While taking warfarin, you should be careful about drinking too much alcohol regularly and avoid binge drinking.
Drinking cranberry juice and grapefruit juice can also interact with warfarin and is not recommended.
The National Institute for Health and Care Excellence (NICE) has approved these medicines for use in treating atrial fibrillation.
NICE also states that you should be offered a choice of anticoagulation and the opportunity to discuss the merits of each medicine.
Unlike warfarin, rivaroxaban, dabigatran, apixaban and edoxaban do not interact with other medicines and do not require regular blood tests.
In large trials, the medicines have been shown to be as effective or more effective than warfarin at preventing strokes and deaths. They also have a similar or lower rate of major bleeding.
You can read more about rivaroxaban, dabigatran and apixaban in the NICE guidance on managing atrial fibrillation.
Edoxaban is recommended as an option for preventing stroke or a blocked artery (embolism) in people with atrial fibrillation who have one or more risk factors, such as:
- heart failure, high blood pressure or diabetes
- a previous history of stroke or transient ischaemic attack (TIA)
- being 75 or older
You can read the NICE guidance about Edoxaban for preventing stroke and systemic embolism in people with non-valvular atrial fibrillation.
Cardioversion may be recommended for some people with atrial fibrillation.
It involves giving the heart a controlled electric shock to try to restore a normal rhythm.
Cardioversion is usually carried out in hospital so the heart can be carefully monitored.
If you have had atrial fibrillation for more than 2 days, cardioversion can increase the risk of a clot forming.
In this case, you'll be given an anticoagulant for 3 to 4 weeks before cardioversion, and for at least 4 weeks afterwards to minimise the chance of having a stroke.
In an emergency, pictures of the heart can be taken to check for blood clots, and cardioversion can be carried out without going on medicine first.
Anticoagulation may be stopped if cardioversion is successful.
But you may need to continue taking anticoagulation after cardioversion if the risk of atrial fibrillation returning is high and you have an increased risk of having a stroke.
Catheter ablation is a procedure that very carefully destroys the diseased area of your heart and interrupts abnormal electrical circuits.
It's an option if medicine has not been effective or tolerated.
Catheters (thin, soft wires) are guided through one of your veins into your heart, where they record electrical activity.
When the source of the abnormality is found, an energy source, such as high-frequency radiowaves that generate heat, is transmitted through one of the catheters to destroy the tissue.
The procedure usually takes 2 to 3 hours, so it may be carried out under general anaesthetic, which means you're unconscious during the procedure.
You should make a quick recovery after having catheter ablation and be able to carry out most of your normal activities the next day.
But you should not lift anything heavy for 2 weeks, and driving should be avoided for the first 2 days.
A pacemaker is a small battery-operated device that's implanted in your chest, just below your collarbone.
It's usually used to stop your heart beating too slowly, but in atrial fibrillation it may be used to help your heart beat regularly.
Having a pacemaker fitted is usually a minor surgical procedure carried out under a local anaesthetic (the area being operated on is numbed and you're conscious during the procedure).
This treatment may be used when medicines are not effective or are unsuitable. This tends to be in people aged 80 or over.