Rate control for atrial fibrillation: medicines, goals and what to expect

Atrial fibrillation is a heart rhythm problem where the heartbeat is not steady. The NHS describes the main symptoms as an irregular pulse, a feeling of the heart pounding, racing or fluttering, a heartbeat faster than 100 beats per minute, tiredness, finding it harder to exercise, chest pain or tightness, and breathlessness or dizziness.

Rate control is a treatment strategy that aims to bring a fast heart rate down so that symptoms ease, without necessarily restoring a normal regular rhythm. The alternative approach, rhythm control, aims to restore and maintain normal rhythm using cardioversion, antiarrhythmic drugs or ablation.

The NHS lists "medicine to control the rate and rhythm of your heart, such as beta blockers" as one part of AF treatment. The other part is medicine to lower the risk of blood clots or stroke (anticoagulants), which works in a completely different way and is needed whichever strategy is chosen.

NICE guideline NG196 on diagnosing and managing atrial fibrillation says rate control should be the first-line strategy except in certain people. The exceptions it lists are people:

• whose AF has a reversible cause;

• who have heart failure thought to be primarily caused by AF;

• with new-onset AF;

• with atrial flutter;

• whose condition is considered suitable for an ablation strategy to restore normal rhythm;

• for whom a rhythm-control strategy is more suitable in the clinician's judgement.

For people who also have heart failure, NICE refers clinicians to its heart failure guideline on using beta-blockers and avoiding calcium-channel blockers such as diltiazem and verapamil.

NICE recommends a stepwise approach to medicines, with the choice based on symptoms, heart rate, other conditions and what the person prefers.

NICE says to consider pharmacological or electrical rhythm control for people whose symptoms continue after the heart rate has been controlled, or for whom rate control has not worked. Options include antiarrhythmic drugs, electrical cardioversion, and, if drug treatment is unsuccessful, unsuitable or not tolerated, left atrial ablation. NICE asks clinicians to explain that ablation is not always effective and that symptom relief may not be long-lasting.

The NHS lists the same wider toolkit: ablation, which burns, freezes or uses high-energy electrical pulses to destroy a section of the heart causing the problem; electrical cardioversion to reset the rhythm; and pacemakers or implantable cardioverter defibrillators in selected people. It adds that sometimes AF is caused by another condition or medicine, and treating the condition or stopping the medicine can improve symptoms.

For people with infrequent episodes and few symptoms, NICE notes that a "no drug treatment" approach or a "pill-in-the-pocket" strategy, where an antiarrhythmic medicine is taken only when an episode starts, may be discussed in suitable cases.

Slowing the heart does not remove the extra risk of blood clots in AF. NICE recommends using the CHA2DS2-VASc score to assess stroke risk, and offering anticoagulation with a direct-acting oral anticoagulant to people with a score of 2 or above, taking bleeding risk into account. It says to consider anticoagulation for men with a score of 1, not to withhold it solely because of a person's age or risk of falls, and not to offer aspirin on its own purely for stroke prevention in AF.

The NHS notes that AF has no cure, but treatment should help manage symptoms and lower the risk of complications such as blood clots, stroke and heart failure. Stroke risk is reviewed over time: NICE advises reassessing stroke risk when a person who is not taking an anticoagulant reaches 65, or develops diabetes, heart failure, peripheral arterial disease, coronary heart disease, or has a stroke or TIA.

The NHS says you should be able to carry on doing most things as usual, including exercise, but to avoid intense exercise and to avoid exercising when you have symptoms. It suggests avoiding triggers such as caffeine, spicy food, stress, dehydration and lack of sleep, keeping to a healthy weight, aiming for at least 150 minutes of moderate exercise a week, stopping smoking, and not drinking too much alcohol.

If you drive you may need to tell the DVLA that you have AF, and the NHS says there may be other practical matters to consider, such as travelling abroad with medicines and insurance. Take your medicines as prescribed, and ask your GP or pharmacist before starting any new medicine, since some medicines the NHS lists as possible AF contributors include levothyroxine, lithium and some asthma medicines such as salbutamol.

The NHS says to call 999 if you currently have a fast or irregular heartbeat together with chest pain, shortness of breath, sweating, feeling or being sick, fainting or dizziness, a severe headache, weakness or numbness on one side of the face or body, blurred vision or loss of sight, or confusion or difficulty speaking. Do not drive yourself to A&E. See a GP if palpitations keep happening or are getting worse, or if treatment is not helping your symptoms.

On the NHS, a GP who suspects AF refers you to a cardiologist, and NICE recommends a 12-lead ECG to confirm the diagnosis. The NHS says tests may also include an echocardiogram, a chest X-ray and blood tests, and that you will have regular check-ups once diagnosed. Private cardiology can offer quicker access to assessments and procedures such as ablation, but the medicines and the underlying guidance are the same.