• Admit (or refer) for urgent assessment and intervention if the person has any of the following:
• A rapid pulse (greater than 150 beats per minute) and/or low blood pressure (systolic blood pressure less than 90 mmHg).
• Loss of consciousness, severe dizziness, ongoing chest pain, or increasing breathlessness.
• A complication of atrial fibrillation (AF), such as stroke, transient ischaemic attack, or acute heart failure.
• Refer people with new-onset AF to a specialist in cardiology if:
• The person is young (for example less than 50 years of age).
• Paroxysmal AF is suspected.
• Rhythm control is the preferred treatment, or there is uncertainty regarding this (see Rate or rhythm control).
• Drug treatment for rate control or antithrombotic treatment that can be used in primary care are contraindicated.
• The person is found to have valve disease or left ventricular systolic dysfunction on echocardiography.
• Wolff–Parkinson–White syndrome or a prolonged QT interval is suspected on the electrocardiogram.
• Heart rate is difficult to control, or the person continues to have symptoms despite rate-control treatment (see Management after starting rate-control treatment).

In depth

• An electrocardiogram should already have been done to confirm the diagnosis of atrial fibrillation. An electrocardiogram may also indicate a possible underlying cause (such as an old myocardial infarction, left ventricular hypertrophy, or a pre-excitation syndrome).
• Do the following tests:
• Thyroid function tests (to exclude hyperthyroidism).
• Full blood count (to exclude anaemia).
• Blood urea and electrolytes, calcium, and glucose measurement (to exclude electrolyte disturbances, which may precipitate atrial fibrillation).
• Liver function tests and clotting screen (to assess suitability for warfarin).
• Chest radiography (to assess a suspected lung abnormality, such as lung cancer; this test may also help to detect heart failure).
• For people not being referred to a cardiologist, consider organizing transthoracic echocardiography if:
• There is a high risk or a suspicion of underlying heart disease (for example signs of heart failure or a cardiac murmur).
• Information on cardiac structure or function is needed to make a decision about starting antithrombotic treatment.
• Most decisions about starting antithrombotic treatment should be based on clinical judgement. Do not routinely organize echocardiography solely for risk stratification if the person meets the clinical criteria to start warfarin.

In depth

• Rate control can be started in primary care, but rhythm control should only be started following specialist assessment.
• Rate control is the preferred treatment for permanent atrial fibrillation (AF) and in people with persistent AF and any of the following:
• More than 65 years of age.
• With coronary artery disease.
• With contraindications to antiarrhythmic drugs.
• Unsuitable for cardioversion.
• Rhythm control is the preferred treatment for paroxysmal AF and in people with persistent AF and any of the following:
• Symptomatic.
• 65 years of age or less.
• Presenting for the first time with lone AF.
• Presenting with AF secondary to a treated or corrected precipitant (such as infection).
• With congestive heart failure.
• If there is uncertainty about which option is best (for example the person may be older than 65 years of age with lone AF), seek specialist advice.

In depth

• Rate-control treatments (beta-blockers, rate-limiting calcium-channel blockers, and digoxin) can be started in primary care, but rhythm-control treatments (such as amiodarone, flecainide, and sotalol) should only be started on specialist advice.
• Start a rate-controlling drug if the person does not require admission, regardless of whether they are to be managed in primary care or have been referred to a specialist for consideration of rhythm control, if:
• The resting heart rate is 90 beats per minute or more, or
• The heart rate is fast on exertion, resulting in a limited exercise tolerance.

In depth

• Offer a beta-blocker or rate-limiting calcium-channel blocker (diltiazem or verapamil), unless this is contraindicated.
• The choice between beta-blocker and calcium-channel blocker will depend on the person's current medication and comorbidities.
• Diltiazem (off-licensed use for atrial fibrillation) is preferred to verapamil because verapamil has a greater negative inotropic effect on the heart and interacts with digoxin.
• For further information, see the prescribing sections on beta-blockers and calcium-channel blockers.
• If the person has a sedentary lifestyle, digoxin is an alternative option.
• Digoxin is only adequate for older, sedentary people in whom rate control is not needed during exercise.
• For further information, see the prescribing section on digoxin.

In depth

• Within 1 week, check whether the person is tolerating the drug and review symptoms, heart rate, and blood pressure.
• If the person cannot tolerate the drug, prescribe an alternative (see Initial drug treatment for rate control).
• If the person's symptoms and/or heart rate are not controlled:
• If they are not taking the maximum drug dose, consider increasing the dose to control symptoms, or
• If they are taking the maximum drug dose, consider combining drug treatments:
• To control symptoms during normal activities only, use a beta-blocker or calcium-channel blocker (diltiazem or verapamil) with digoxin.
• To control symptoms during normal activities and during exercise, use a calcium-channel blocker (diltiazem or verapamil) with digoxin. If the person is already taking a beta-blocker, it may be more practical to add in digoxin first, and if symptoms are still not controlled, then switch the beta-blocker with a calcium-channel blocker.
• Do not use a combination of a beta-blocker and a rate-limiting calcium-channel blocker to control atrial fibrillation in primary care.
• If symptoms are not controlled with a beta-blocker plus digoxin or a calcium-channel blocker plus digoxin, refer to a specialist in cardiology.
• For detailed prescribing information, see the prescribing sections on beta-blockers, calcium-channel blockers, and digoxin.

In depth

• All people with atrial fibrillation (whether paroxysmal, persistent, or permanent) should be offered antithrombotic treatment to reduce their risk of stroke.
• Offer either aspirin or warfarin, without delay, after confirming a diagnosis of atrial fibrillation.
• The choice of either aspirin or warfarin should be based on the person's risk of stroke (see Which antithrombotic treatment).

In depth

• Treatment decisions should be made on an individual basis; the person's bleeding risk, likelihood of compliance with treatment, and preferred options should always be fully assessed before starting treatment.
• Offer people with atrial fibrillation (AF):
• At low risk of stroke — aspirin.
• At high risk of stroke — warfarin.
• At moderate risk of stroke — either aspirin or warfarin.
• If uncertain about stroke risk, start aspirin whilst awaiting specialist assessment.
• CKS does not recommend the use of clopidogrel or a combination of aspirin and clopidogrel for AF in primary care.
• Risk factors have a cumulative effect on stroke risk; this should be considered when discussing treatment options. For example, if the person is in the moderate stroke risk category but has more than one risk factor for stroke (that is, more than one of hypertension, diabetes, coronary artery disease, or peripheral artery disease), there may be a stronger case for choosing warfarin over aspirin.
• For detailed information on the use of aspirin and warfarin in AF, including contraindications, starting doses and titration, monitoring, and adverse effects, see the CKS topics on Antiplatelet treatment and Anticoagulation - oral.

In depth

• Assess the person's risk of stroke using the following criteria:
• High risk of stroke:
• Previous ischaemic stroke/transient ischaemic attack or thromboembolic event.
• 75 years of age or more with risk factors (hypertension, diabetes, coronary artery disease, peripheral artery disease).
• Clinical evidence of valve disease or heart failure, or impaired left ventricular function on echocardiography.
• Moderate risk of stroke:
• 65 years of age or more without risk factors.
• Less than 75 years of age with risk factors.
• Low risk of stroke:
• Less than 65 years of age without risk factors.
• The CHADS₂ tool can be used to calculate the risk of stroke (see assessing stroke risk for more details).
• Risk factors have a cumulative effect on stroke risk; this should be considered when discussing treatment options (see Which antithrombotic treatment).
• If uncertain about the person's risk of stroke, consider referral to a cardiologist.

In depth

• Advise the person that it is their responsibility to inform the Driver and Vehicle Licensing Agency (DVLA) of any condition that may affect their ability to drive.
• The DVLA's medical rules regarding atrial fibrillation are:
• For group 1 entitlement (cars, motorcycles):
• Driving must cease if the arrhythmia has caused or is likely to cause incapacity.
• Driving may be permitted when the underlying cause has been identified and controlled for at least 4 weeks
• The DVLA need not be notified unless there are distracting or disabling symptoms.
• For group 2 entitlement (lorries, buses):
• Disqualified from driving if the arrhythmia has caused or is likely to cause incapacity.
• Driving may be permitted when the arrhythmia is controlled for at least 3 months; the left ventricular ejection fraction is equal to or greater than 0.4; there is no other disqualifying condition.
• The person should check with their insurer that they are still covered for driving.
• The latest information from the DVLA regarding medical fitness to drive can be obtained at www.dvla.gov.uk/medical/ataglance.

In depth

In depth

• Advise the person that there are no flying restrictions provided they have stable atrial fibrillation which has not recently worsened or become more symptomatic.

In depth

In depth