“This section of the website details how your AF should be managed. It will help you to understand diagnosis and treatment, so that you can be active in managing your condition.”Dr Raj Patel, Consultant Haematologist, King's Thrombosis Centre, Department of Haematological Medicine
Management of atrial fibrillation
Treatment of AF varies depending on factors including:
- The type of AF
- Treatment of any underlying cause
- Overall health
You may be treated by your GP or referred to a heart specialist, known as a cardiologist or electrophysiologist. The first steps are to reduce your risk of AF-related stroke, improve your quality of life and investigate the cause of the AF. If a cause is found, you may only need treatment for this. For example, hyperthyroidism (an overactive thyroid gland) may cause AF, so medication to correct the underlying condition will treat AF.
If no underlying cause can be found, the treatment options are:
Please remember that not all of the treatments listed below will be suitable for you. Your healthcare professional (HCP) will assess your individual needs and define your personalised treatment plan.
- Medicines to reduce the risk of an AF-related stroke
- Medicines to control AF
- Cardioversion (electric shock treatment)
- Catheter ablation
Medicines to reduce the risk of an AF-related stroke
The way the heart beats in AF means there is a risk of blood clots forming in the heart chambers. If these enter the bloodstream, they can cause an AF-related stroke.
All people with AF (except those with the lowest risk of having a stroke) should be offered anticoagulation treatment. Anticoagulation means that you take a medicine to reduce the chance of a blood clot forming and having an AF-related stroke. Some people call anticoagulation "thinning the blood" although the blood is not actually made any thinner.
Warfarin has been the anticoagulant medicine traditionally used, though new medicines have recently been developed. All anticoagulants work by interacting with certain chemicals in the blood to prevent blood clots forming so easily.
They reduce the risk of stroke by nearly two thirds for people with AF. In other words, these treatments can prevent about six out of ten strokes that would have occurred without treatment.1
Types of anticoagulants
Warfarin, a vitamin K antagonist (VKA), has been the most commonly used anticoagulant medicine. However, there is an increased risk of bleeding in people who take warfarin and it can interact with many medicines and some food and drinks. This is why if you take warfarin you will need regular blood tests (INR tests) to check how quickly your blood clots. The aim is to get the dose of warfarin just right so your blood does not clot as easily as normal, but not so much as to cause bleeding problems. Speak to your HCP if you have questions about taking warfarin.
Novel oral anticoagulants (novel OACs)
You may also hear novel OACs referred to as new OACs, NOACs, non-VKA antagonists, xabans and DTIs.
Apixaban, dabigatran and rivaroxaban are known as novel OACs and may be used as an alternative to warfarin. Compared to warfarin, these novel OACs do not have the same interactions with other medications or food and drink, so you do not require regular blood tests. If you have had trouble getting your INR level just right, your HCP may suggest one of these medicines as an alternative to warfarin.
Although not an anticoagulant, aspirin has been traditionally used to slow blood clotting, but is no longer recommended. If you take aspirin for AF you should make an appointment to discuss it with your HCP.
Medicines to control AF
A rate control strategy aims to use medication to slow the speed of the heart in order to alleviate symptoms, help protect against heart failure and reduce the likelihood of AF-related stroke and other complications. A number of different types of drugs are available and you may need to try different combinations before the medications which suit you best are found. Medications are also used in a rhythm control strategy when they can convert the AF back to a normal rhythm.
Beta blockers are used to slow the heart rate and are also useful in keeping AF away if the heart rhythm has been restored to normal. Most commonly bisoprolol is prescribed but metolprolol, atenolol or propanolol are also used. Sotalol is another beta blocker but it is no longer recommended for heart rate control. Patients taking beta blockers will need their blood pressure and heart rate checked regularly by their GP. Beta blockers are not recommended in patients with asthma or emphysema or patients with slow heart rates.
There are several calcium-channel blockers but the most commonly prescribed are those that are more effective at controlling a fast heart rate, e.g. verapamil and diltiazem. They can be used alone or in combination with beta blockers or digoxin. Verapamil in particular can be useful in maintaining a normal heart rhythm if it has been restored from AF.
Digoxin can be effective in controlling the heart rate at rest, but it rarely controls the heart rate during exercise. It is therefore only used for people who do not exercise unless a beta blocker or calcium-channel blocker is also being taken. It is not used for people with paroxysmal AF.
Antiarrhythmic drugs such as amiodarone and flecainide are sometimes used to control fast heart rates that do not respond to other medications. Sometimes they are used to help restore the heart to a normal rhythm on their own, or to help during and after cardioversion. They are very strong drugs and are not recommended for everyone. Dronedarone is another antiarrhythmic drug that is only recommended for people who need help to maintain a normal heart rhythm after cardioversion. Amiodarone is not usually recommended to be taken for more than 12 months. Sotalol is a beta blocker that has an antiarrhythmic effect at high doses only. It is no longer recommended for rhythm control as high doses can increase side effects and can be dangerous.
Pill in the pocket
'Pill in the pocket' is a pill that is taken at the time a person get AF in order to restore the normal rhythm, rather than a therapy that aims to prevent AF. A 'pill in the pocket' approach is not commonly recommended, but it can be useful for some people to terminate single episodes of AF (paroxysms) The drug flecainide is carried by the patient and may be taken as a single dose at the beginning of the attack. This is safe if the patient is properly educated when it is supplied.
Cardioversion is a term used for restoring the heart from AF to its normal regular rhythm. Some medications can do this, but more commonly electricity is required. This is called DC cardioversion and involves a controlled electric shock applied across the chest using a cardiac defibrillator. The procedure takes place in hospital under a general anaesthetic. The treatment takes a few minutes but a patient is kept in hospital a few hours while the heart is carefully monitored and the anaesthetic wears off.
Anticoagulation drugs must be given prior to the procedure if AF has been present for more than 48 hours to minimise the chance of having an AF-related stroke. Your doctor will advise on which is best for you to take and dosing. You must take an anticoagulant for at least four weeks before cardioversion to ensure there are no blood clots in your heart. If you take warfarin you will need weekly INR tests for four weeks prior to the procedure during which time you must maintain an INR of two or more. If the cardioversion is successful, anticoagulation and other medications may no longer be needed. However, some people may need to continue with medication for life if the treatment was unsuccessful, if your healthcare professional believes you have a significant risk of your AF returning, or you are still at high risk from AF-related stroke.
Cardioversion is considered an extremely low risk procedure if the recommended anticoagulation regime has been followed. Speak to your cardiologist or specialist nurse about any concerns you may have.
The best candidates for cardioversion are young, active, or recently diagnosed AF patients who are in otherwise good health - for instance no underlying heart disease. It is usually recommended for people who still have significant symptoms of AF while taking rate controlling medication.
DC cardioversion can also be performed using a transoesophageal echocardiogram (TOE). This is an ultrasound scan where a probe is swallowed. The probe is positioned right next to the left atrium where a doctor can look into the left atrial appendage for blood clots. If none are seen it is safe to go ahead with the cardioversion without the need for four weeks of an OAC before. However, you still need to be taking an OAC.
DC cardioversion is 80-90% effective for selected patients. However, due to its complex nature AF can easily return. Of those patients for which cardioversion was successful 50% will revert to AF within 12 months and 80% within five years.
Ablation is a procedure reserved for those with continued symptoms that impact significantly on quality of life or where medical therapy has been unsuccessful. The ablation procedure is considered ‘complex’ and can only be performed by highly skilled specialists called electrophysiologists (EP) who you must be referred to by your cardiologist.
Catheters (thin, soft wires) are guided through one of your veins into your heart, where they record electrical activity. When the source of the abnormal electrical impulses are found, an intense energy source is transmitted through one of the catheters to create a very small amount of scar tissue. This does not damage the function of the heart. The energy can come from high-frequency radiowaves that generate heat (radiofrequency ablation) or through freezing (cryoablation). Commonly a line is ‘drawn’ around the pulmonary veins which creates a sort of firewall around them (pulmonary vein isolation). The abnormal impulses causing AF continue to fire but they cannot transmit themselves across the firewall, therefore allowing the natural pacemaker to re-take control. Catheter ablation can be performed under either a local or general anaesthetic.
The procedure has reasonably high success rates in selected patients, but does not suit every AF patient. It comes with risks and complications that will be fully discussed with you by your HCP. It is considered a treatment for symptom control rather than AF-related stroke prevention.
Surgical ablation uses the same principal of making a ‘firewall’ as catheter ablation but a surgeon uses a scalpel to create the scar tissue. This is only performed during cardiac surgery such a coronary artery bypass or valve repair/replacement. It is commonly called the Maze or Cox Maze procedure.
Left atrial appendage occlusion (LAAO)
The left atrial appendage (LAA) is a small ‘pocket’ in the left atrium where the blood clots causing AF-related stroke are commonly formed. The LAA can be removed surgically or blocked off using an implantable device such as the Watchman. These procedures are not commonly used and are still being researched. They may be considered only if you cannot take anticoagulants. They are not routinely offered as an alternative to anticoagulation for AF-related stroke prevention at present.
A pacemaker is a special electronic device implanted under the skin which stimulates the heart muscle and regulates its contractions. They are usually used for people who have a problem with the electrical connection between the atria and the ventricles. They can also be used for people with AF who have a particular difficulty with a fast heart rate. The same electrical connection is permanently severed using the ablation technique and the pacemaker takes over the regulation of the heart rate gaining control of its overall speed. This is not a cure for AF as the atria continue to fire in an irregular state. The pacemaker can be programmed to fire at a rate which suits the individual. It is known as the pace and ablate strategy and is usually only recommended for patients who have continued symptoms despite medical treatment or have heart failure thought to be caused by a continued fast heart rate. It is not a treatment to be taken lightly as you will be dependent on the pacemaker for life. However it can help regain control over the level of symptoms experienced.
Monitoring and check-ups
It is important to visit your GP and/or cardiologist regularly so they can monitor your AF and manage your treatment. They should also check your blood pressure and heart rate regularly.
If you are taking warfarin your blood will need to be checked on a regular basis. The ability of warfarin to make the blood less likely to clot, can be affected by a number of factors such as food and other medications. Regular monitoring, measured by INR, ensures that INR is not to low (risk of clots) or too high (risk of bleeding). Your medication can then be adjusted if necessary depending on the result, to ensure your INR remains within the target required for your condition - called your therapeutic range – which will be decided by your GP or consultant.
How to take your medicine effectively
It is also very important that you take your medication as directed by your HCP at the right time and with food as necessary. If it is important to take your medicines at the same time every day, try to incorporate into your daily routine such as with breakfast. You could leave a note on the fridge or set an alarm called ‘AF pills’ on your mobile phone at the same time each day.
If you are experiencing any problems with your medication it is important to continue to take it and contact your healthcare professional straight away.
1. Patient UK, Atrial Fibrillation. Available from: http://www.patient.co.uk/print/4198. Accessed April 2014