New-onset atrial fibrillation

Overview 
Theory 
Diagnosis 
Management 
Follow up 
Resources 

Please note that formulations/routes and doses may differ between drug names and brands, drug formularies, or locations. Treatment recommendations are specific to patient groups: see disclaimer

ACUTE

haemodynamically unstable

1st line – emergency electrical cardioversion

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1st line –

emergency electrical cardioversion

Identify any patient with uncontrolled fast AF who has features of:[1][3]

Acute or worsening haemodynamic instability[1]
- Syncope, owing to global reduction in blood flow to the brain
- Acute pulmonary oedema
- Ongoing myocardial ischaemia; typical ischaemic chest pain and/or evidence of myocardial ischaemia on 12-lead ECG
- Symptomatic hypotension; systolic blood pressure <90 mmHg
- Cardiogenic shock; see Shock
Heart failure
- Pulmonary oedema and/or raised jugular venous pressure
Evidence of ventricular pre-excitation on ECG with rapid antegrade conduction, as seen in people with Wolff-Parkinson-White syndrome
- Patients with Wolff-Parkinson-White syndrome and AF are at risk of fast ventricular rates resulting from rapid conduction of atrial electrical activity to the ventricles via the accessory pathway, and at increased risk of ventricular fibrillation and sudden death[1]
- See Wolff-Parkinson-White syndrome.

Do not delay emergency synchronised direct current (DC) cardioversion in these groups, regardless of the duration of onset of the patient’s arrhythmia, as their condition may be life-threatening.

Electrical cardioversion quickly and effectively converts AF to sinus rhythm.[1]
Electrical cardioversion restores sinus rhythm quicker and more effectively than pharmacological cardioversion and is associated with shorter hospital stays.[66]
Do not use pharmacological cardioversion in haemodynamically compromised patients.[1]

Urgently admit to an acute medical unit.[32]

Call for anaesthetic support to sedate the patient before DC cardioversion.[1]

This will usually be with a short-acting general anaesthetic.

Seek senior and/or specialist review; this should not delay urgent DC cardioversion.[1][3] Further treatment after emergency electrical cardioversion should only be initiated by a specialist.

Check the patient’s oral anticoagulation status as soon as possible.[1] In patients not already on therapeutic anticoagulation, immediately start anticoagulation pre-cardioversion. See Pre-cardioversion anticoagulation below. This is important to prevent potential thromboembolic complications and should be given in a timely manner even in haemodynamically unstable patients.[1]

Record and store an ECG rhythm strip during and immediately after shock delivery.

Continuously monitor the patient’s blood pressure and oximetry during the procedure.[1][67]

Practical tip

Ensure the defibrillator is synchronised and that it remains synchronised between shocks.

If initial attempts at DC cardioversion fail, ensure there is good skin-to-electrode contact with the pads in the anteroposterior position.

In patients with AF duration of more than 24 hours who are undergoing cardioversion, initiate oral anticoagulation for at least 4 weeks after cardioversion.[1] Use a direct oral anticoagulant in preference to a vitamin K antagonist.[1]

This is an optional step for those with AF onset definitely less than 24 hours.[1]

Beyond 4 weeks, base decisions about long-term anticoagulation on associated stroke risk factors, as per the patient’s CHA ₂DS ₂-VASc score .[1][3][34] [ Atrial Fibrillation CHA(2)DS(2)-VASc Score for Stroke Risk Opens in new window ] See Longer-term anticoagulation strategy below.

Be aware that some patients may develop sinus bradycardia after successful DC cardioversion. Ensure there are provisions for the use of intravenous atropine or isoprenaline or temporary transcutaneous pacing to manage post-cardioversion bradycardia until the patient stabilises.[1]

Consider – pre-cardioversion anticoagulation

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Consider –

pre-cardioversion anticoagulation

Additional treatment recommended for SOME patients in selected patient group

Check the patient’s oral anticoagulation status as soon as possible.[1] In patients not already on therapeutic anticoagulation, immediately start anticoagulation pre-cardioversion. Use a low molecular weight heparin (LMWH), such as enoxaparin, or unfractionated heparin.[3]

This is important to prevent potential thromboembolic complications and should be given in a timely manner even in haemodynamically unstable patients.[1]

After cardioversion, transition patients who are started on a LMWH or unfractionated heparin to a DOAC, such as rivaroxaban, apixaban, edoxaban, or dabigatran, or warfarin when appropriate.[1] See Longer-term anticoagulation strategy below.

Primary options

heparin: consult specialist for guidance on dose

enoxaparin: consult specialist for guidance on dose

Plus – treat underlying cause

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Plus –

treat underlying cause

Treatment recommended for ALL patients in selected patient group

Identify and manage risk factors and concomitant conditions.[1] Correct, where possible, treatable causes of AF or refer, as appropriate.[1][32] Use local policies and guidelines alongside your clinical judgement to determine urgency.

In practice, refer to a cardiologist, any patient:
- Who is young and has suspected underlying structural heart disease
- With a pre-excitation syndrome such as Wolff-Parkinson-White syndrome.[53] See Wolff-Parkinson-White syndrome
- With valvular heart disease associated with AF
- With suspected heart failure.

Practical tip

Signs of stroke or heart failure may be subtle in some instances.

Bear in mind that rhythm control is often unsuccessful in critically ill patients and those with severely impaired ventricular systolic function, because AF is often precipitated/exacerbated by increased sympathetic tone, inotropes, and vasopressors.[1] In these patients, work to identify and correct precipitating factors and secondary causes and optimise background treatment.[1]

Consider – amiodarone

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Consider –

amiodarone

Additional treatment recommended for SOME patients in selected patient group

Consider intravenous amiodarone for acute control of heart rate in these patients.[1] Only do this with advice from a specialist.

Do not use rate control drugs in people with AF with a pre-excitation syndrome such as Wolff-Parkinson-White syndrome.[1] In practice, seek advice from a specialist or senior colleague to determine suitable alternatives. See Wolff-Parkinson-White syndrome.

These drugs accelerate conduction down the accessory pathway to the ventricle putting the patient at risk of life-threatening arrhythmias, such as ventricular fibrillation and sudden death.[1]
AF is the second most common arrhythmia in Wolff-Parkinson-White syndrome, occurring in approximately one third of patients.[1]
Atrial activity predominantly conducts down the accessory pathway, causing ventricular pre-excitation.
The ECG will show a fast, broad QRS irregular rhythm with delta waves.

Primary options

amiodarone: 5 mg/kg intravenously over 20-120 minutes initially, repeat infusion according to response, maximum 1200 mg/day

The European Society of Cardiology recommends 300 mg intravenously over 30-60 minutes initially, followed by 900-1200 mg intravenously over 24 hours.[1]

Plus – longer-term anticoagulation strategy

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Plus –

longer-term anticoagulation strategy

Treatment recommended for ALL patients in selected patient group

After cardioversion, continue anticoagulation. If the patient has been started on parenteral anticoagulation before cardioversion, transition them to an appropriate oral anticoagulant.

Use the CHA ₂DS ₂-VASc score to calculate stroke risk in all patients presenting with AF.[1][3] [ Atrial Fibrillation CHA(2)DS(2)-VASc Score for Stroke Risk Opens in new window ]

Consider oral anticoagulation for stroke prevention in men with a CHA ₂DS ₂-VASc score of 1 or more and women with a score of 2 or more.[1][3] In these groups, continue anticoagulation long-term.[1]
Guidelines from the European Society of Cardiology (ESC) give an additional, stronger recommendation for higher CHA ₂DS ₂-VASc scores; the ESC recommends commencing oral anticoagulation in AF patients with a CHA ₂DS ₂-VASc score of 2 or more in men and 3 or more in women.[1]

If you are considering anticoagulation, use the ORBIT score or the HAS-BLED score to:[1][3][34][36] [ ORBIT Bleeding Risk Score Opens in new window ] [ HAS-BLED Bleeding Risk Score Opens in new window ]

Assess the risk of a major bleed
Identify (and subsequently manage) modifiable risk factors for bleeding, such as uncontrolled hypertension, harmful alcohol consumption, labile international normalised ratio (INR; if the patient is on warfarin), concurrent use of medication (including antiplatelets, selective serotonin reuptake inhibitors, and non-steroidal anti-inflammatory drugs), and reversible causes of anaemia
Flag the ‘high bleeding risk’ patients for early (4 weeks as opposed to 4-6 months) review and follow-up.

Guidelines from the ESC recommend use of the HAS-BLED score.[1] The National Institute for Health and Care Excellence (NICE) recommends use of the ORBIT score where possible, but either HAS-BLED or ORBIT is acceptable.[3]

Do not use bleeding risk scores to exclude anticoagulant treatment; a high score should not rule out anticoagulation.[64]

Bleeding risk is dynamic and requires regular re-assessment; it should not be based on a single one-off assessment.[65]

Practical tip

A history of falls is not an independent predictor of bleeding on oral anticoagulants. A modelling study estimated that a patient would need to fall 295 times per year for the benefits of ischaemic stroke reduction with oral anticoagulants to be outweighed by the potential for serious bleeding.[1]

Practical tip

Follow your local protocol when choosing a bleeding risk score. 2020 guidelines from the ESC recommend use of the HAS-BLED score.[1] NICE recommends preferential use of the ORBIT score in its 2021 guideline.[3] However, subsequently published data show no advantage of ORBIT over HAS-BLED, even in patients taking direct oral anticoagulants, and suggest that in some circumstances ORBIT performs worse.[68][69][70] The use of either score is reasonable, and the choice of bleeding risk score is less important than failure to consider anticoagulation at all.

When indicated by the CHA ₂DS ₂-VASc score, start oral anticoagulation as soon as possible.[1]

Use a direct oral anticoagulant (DOAC) in preference to a vitamin K antagonist.[1][3]

Discuss the options for anticoagulation with the patient and base the choice on their clinical features and preferences.[1][3]

Before starting anticoagulation treatment, specifically discuss the potential risks and benefits with the patient, as part of the shared decision-making process, explaining that:[3]
- For most people the benefit of anticoagulation outweighs the bleeding risk
- For people with an increased risk of bleeding the benefit of anticoagulation may not always outweigh the bleeding risk, and careful monitoring of bleeding risk is important.

If using a DOAC, choose one of apixaban, edoxaban, rivaroxaban, or dabigatran.[1] The choice of DOAC should be tailored to the person's clinical needs and preferences.[3]

DOACs have non-inferior efficacy and are possibly safer, particularly in terms of major bleeding, compared with warfarin.[71] [ ] [Evidence A] Unlike warfarin, DOACs don’t require laboratory anticoagulation monitoring.[72][73]

If using warfarin, start the patient on a parenteral anticoagulant (if they aren’t on one already as part of the pre-cardioversion anticoagulation), such as unfractionated heparin or a low molecular weight heparin, at the same time. Ensure INR is in the range of 2.0 to 3.0 before ceasing the parenteral anticoagulant.[1][3][32] Ensure follow-up to maintain the patient’s time in therapeutic range (TTR) >65%.[3] This approach is in line with recommendations from NICE and reflects common practice in the UK. Bear in mind, however, that guidelines from the ESC recommend maintaining TTR >70%.[1]

Do not offer aspirin monotherapy solely for stroke prevention to people with AF.[3]

A specialist may consider non-drug options in the presence of absolute contraindications to oral anticoagulants, including:[1]

Active serious bleeding (where the source should be identified and treated)
Associated comorbidities (e.g., severe thrombocytopenia <50 platelets/microlitre, severe anaemia under investigation, etc.)
A recent high-risk bleeding event such as intracranial haemorrhage.

Primary options

apixaban: 2.5 to 5 mg orally twice daily

edoxaban: body weight <61 kg: 30 mg orally once daily; body weight ≥61 kg: 60 mg orally once daily

rivaroxaban: 20 mg orally once daily

dabigatran: 18-74 years of age: 150 mg orally twice daily; 75-79 years of age: 110-150 mg orally twice daily; ≥80 years of age: 110 mg orally twice daily

Secondary options

warfarin: 5-10 mg orally once daily initially, adjust dose according to target INR

haemodynamically stable: onset <48 hours

1st line – rate control

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1st line –

rate control

Use rate control to slow the patient’s heart rate in the presence of tachycardia.[1][2][3] In practice, do this while initially assessing the patient.

Rate control is often sufficient to improve AF-related symptoms.[1]
Bear in mind that there is very little in the way of robust evidence to inform the best type and intensity of rate control treatment.[1]

Use atrioventricular nodal blocking drugs – either a standard beta-blocker (that is, a beta-blocker other than sotalol) such as bisoprolol, metoprolol, esmolol, or carvedilol, or a rate-limiting non-dihydropyridine calcium-channel blocker (diltiazem or verapamil) – as initial monotherapy.[1][3] Base the choice of drug on the person's symptoms, heart rate, comorbidities, and preferences when considering drug treatment.[3]

These are preferred first-line options as they have rapid onset of action and are effective for high sympathetic tone.[74][75][76][77][78]
Bear in mind that rate-limiting calcium-channel blockers are contraindicated in patients with heart failure with reduced ejection fraction (a common comorbidity).
Alternative drugs are available. Seek advice from a specialist on the best option for your individual patient.
- Consider digoxin monotherapy if the patient is sedentary (they do no or very little physical exercise) or if other rate-limiting drugs are not appropriate because of comorbidities or patient preferences.[3] In practice, this is also a good option for older patients.

If monotherapy does not control symptoms, and if continuing symptoms are thought to be due to poor ventricular rate control, consider combination therapy with any two of the following:[3]

A beta-blocker
Diltiazem
- Bear in mind that this is contraindicated in people with heart failure with reduced ejection fraction.[1] See Acute heart failure
Digoxin.

Do not offer amiodarone for rate control in these patients. The National Institute for Health and Care Excellence (NICE) recommends against use of long-term amiodarone (longer than 12 months) due to lack of evidence and the risk of serious side effects.[3] You should only consider amiodarone for rate control in critically ill patients and those with severely impaired ventricular systolic function under the advice of a specialist.[1]

Practical tip

In stable patients, oral therapy is reasonable. If the patient is stable but you wish to achieve more rapid rate control, intravenous administration is a better choice than oral. Intravenous administration is also useful for observation of acute adverse effects (as infusion can be discontinued promptly) and therefore appropriate dose titration.

These drugs accelerate conduction down the accessory pathway to the ventricle putting the patient at risk of life-threatening arrhythmias, such as ventricular fibrillation and sudden death.[1]

Primary options

bisoprolol: 1.25 mg orally once daily initially, increase gradually according to response, maximum 20 mg/day

metoprolol: 2.5 to 5 mg intravenously initially (at a rate of 1-2 mg/minute), may repeat every 5 minutes if required, maximum 10-15 mg/total dose; 50 mg orally (immediate-release) two to three times daily initially, increase gradually according to response, maximum 300 mg/day

The European Society of Cardiology recommends a maximum intravenous dose of 20 mg/total dose, and an oral (immediate-release) dose of 25-100 mg twice daily.[1]

esmolol: 500 micrograms/kg/minute intravenous infusion for 1 minute as a loading dose, followed by 50 micrograms/kg/minute infusion for 4 minutes, consult specialist for guidance as further dose titration depends on response; usual maintenance dose 50-200 micrograms/kg/minute

The European Society of Cardiology recommends a maximum dose of 300 micrograms/kg/minute.[1]

carvedilol: 3.125 mg orally twice daily initially, increase gradually according to response, maximum 50 mg/day (body weight <85 kg) or 100 mg/day (body weight >85 kg)

verapamil: 5-10 mg intravenously over 2 minutes, may repeat after 5-10 minutes if required; 40-120 mg orally (immediate-release) three times daily initially, increase gradually according to response, maximum 480 mg

The European Society of Cardiology recommends a dose of 2.5 to 10 mg intravenously over 5 minutes. An extended-release oral formulation may be used if available.[1]

diltiazem: 60 mg orally (immediate-release) three times daily initially, increase gradually according to response, maximum 360 mg

The European Society of Cardiology recommends intravenous diltiazem as a treatment option; however, this formulation is not available in the UK. An extended-release oral formulation may be used if available.[1]

Secondary options

digoxin: 0.75 to 1.5 mg orally given in divided doses over 24 hours for rapid digitalisation, followed by maintenance dose of 0.125 to 0.25 mg/day

These drug options and doses relate to a patient with no comorbidities.

Primary options

bisoprolol: 1.25 mg orally once daily initially, increase gradually according to response, maximum 20 mg/day

The European Society of Cardiology recommends a maximum intravenous dose of 20 mg/total dose, and an oral (immediate-release) dose of 25-100 mg twice daily.[1]

The European Society of Cardiology recommends a maximum dose of 300 micrograms/kg/minute.[1]

carvedilol: 3.125 mg orally twice daily initially, increase gradually according to response, maximum 50 mg/day (body weight <85 kg) or 100 mg/day (body weight >85 kg)

The European Society of Cardiology recommends a dose of 2.5 to 10 mg intravenously over 5 minutes. An extended-release oral formulation may be used if available.[1]

diltiazem: 60 mg orally (immediate-release) three times daily initially, increase gradually according to response, maximum 360 mg

Secondary options

digoxin: 0.75 to 1.5 mg orally given in divided doses over 24 hours for rapid digitalisation, followed by maintenance dose of 0.125 to 0.25 mg/day

Back to drug information with added comorbidities

Drug choice, dose and interactions may be affected by the patient's comorbidities. Check your local drug formulary.

Show drug information for a patient with no comorbidities

Primary options

bisoprolol

metoprolol

esmolol

carvedilol

verapamil

diltiazem

Secondary options

digoxin

Plus – consider early rhythm control

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Plus –

consider early rhythm control

Treatment recommended for ALL patients in selected patient group

Check the patient’s oral anticoagulation status.[1]

If the patient is not on anticoagulation, assess bleeding risk using the ORBIT score or the HAS-BLED score and then start anticoagulation pre-cardioversion as soon as possible.[3] [ ORBIT Bleeding Risk Score Opens in new window ] [ HAS-BLED Bleeding Risk Score Opens in new window ] See Pre-cardioversion anticoagulation below.
Beyond 4 weeks, base decisions about long-term anticoagulation on associated stroke risk factors, as per the patient’s CHA ₂DS ₂-VASc score .[1][3][34] [ Atrial Fibrillation CHA(2)DS(2)-VASc Score for Stroke Risk Opens in new window ] See Longer-term anticoagulation strategy below.

Choose early or delayed cardioversion.[1]

In patients with AF duration 24 to 48 hours who are undergoing cardioversion, initiate oral anticoagulation for at least 4 weeks after cardioversion.[1] Use a direct oral anticoagulant in preference to a vitamin K antagonist.[1]
This is an optional step for those with AF onset definitely less than 24 hours.[1]

Practical tip

In patients with onset of the arrhythmia definitely less than 48 hours, use early rhythm control rather than delayed rhythm control or rate control alone if it is feasible within the treatment setting and appropriate to patient characteristics, clinical presentation, and preferences. This may result in earlier symptom relief for the patient.

Consider either pharmacological or electrical cardioversion depending on clinical circumstances, patient preferences, and resources, to reduce symptoms.[1][3]

Electrical cardioversion restores sinus rhythm quicker and more effectively than pharmacological cardioversion and is associated with shorter hospital stays.[1][66] Pharmacological cardioversion, however, does not require fasting or sedation.

Electrical cardioversion is achieved with synchronised direct current (DC) cardioversion. Pharmacological cardioversion uses an anti-arrhythmic drug, selected according to the patient’s history and condition.[1]
In haemodynamically stable patients, the decision to use electrical or pharmacological cardioversion will depend on local expertise, facilities and drugs available, the availability of a suitable clinician to administer sedation if electric cardioversion is selected, and patient preference.

Electrical cardioversion

Seek anaesthetic support to sedate the patient before DC cardioversion.[1]

Intravenous sedation should not be administered in the fed state as this increases the risk of aspiration. The anaesthetist will also be able to advise how long the patient should be fasting for safe sedation.

Record and store an ECG rhythm strip during and immediately after shock delivery.

Continuously monitor the patient’s blood pressure and oximetry during the procedure.[1][67]

Bear in mind that some patients may develop sinus bradycardia after successful DC cardioversion. Ensure there are provisions for the use of intravenous atropine or isoprenaline or temporary transcutaneous pacing to manage post-cardioversion bradycardia until the patient stabilises.[1]

Practical tip

Ensure the defibrillator is synchronised and that it remains synchronised between shocks.

If initial attempts at DC cardioversion fail, ensure there is good skin-to-electrode contact with the pads in the anteroposterior position.

Pharmacological cardioversion

Bear in mind that pharmacological cardioversion requires continuous medical supervision and ECG monitoring, regardless of the drug used, to detect a pro-arrhythmic event.[79]

In practice, this will usually be undertaken in a cardiac monitoring bed (e.g., in the cardiac care unit or a resuscitation bed in the accident and emergency department).

Use an anti-arrhythmic drug, selected according to the patient’s history and the overall clinical picture.[1][3] The National Institute for Health and Care Excellence in the UK recommends offering:[3]

A choice of flecainide or amiodarone to people with no evidence of structural or ischaemic heart disease
or
Amiodarone to people with evidence of structural heart disease
- You will need a large-bore cannula for amiodarone.

Other anti-arrhythmics used outside of the UK include:[1]

Vernakalant – although available in the UK, it is rarely used
Ibutilide – not available in the UK.

Seek specialist opinion from a cardiologist if you are unsure about which drug to use.

Do not use sotalol.[3]

If using a class 1C anti-arrhythmic (e.g., flecainide), co-prescribe an atrioventricular (AV) nodal blocking agent (e.g., rate-limiting calcium-channel blocker or beta-blocker) if the patient is not already taking an AV nodal blocking agent. This is to prevent accelerated ventricular responses.[1]

Using a sodium-channel blocker such as flecainide without an AV nodal blocking agent can convert to a slower atrial flutter rhythm, which allows the AV node to conduct in a 1:1 fashion and paradoxically results in faster ventricular response.[1]
Although this can occur in the acute situation of pharmacological cardioversion it is more important when considering these drugs for longer-term management to prevent recurrent AF.
Bear in mind that flecainide can only be used in the absence of structural heart disease/past ischaemic heart disease.
If in doubt, seek specialist cardiology advice.

Primary options

flecainide: 200-300 mg orally as a single dose

The European Society of Cardiology recommends intravenous flecainide as a treatment option at a dose of 2 mg/kg intravenously over 10 minutes; however, this formulation is not available in the UK.[1]

amiodarone: 5-7 mg/kg intravenously over 1-2 hours, followed by 50 mg/hour intravenous infusion, maximum 1200 mg/day

Consider – pre-cardioversion anticoagulation

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Consider –

pre-cardioversion anticoagulation

Additional treatment recommended for SOME patients in selected patient group

Check the patient’s oral anticoagulation status.[1]

If the patient is already on therapeutic anticoagulation:
- Check international normalised ratio (INR), if possible, in patients already taking warfarin before electrical cardioversion to confirm good anticoagulant adherence, with the INR within therapeutic range for 3 weeks prior to cardioversion. In patients already taking a direct oral anticoagulant (DOAC), confirm they have been on an appropriate dose with good adherence to treatment for 3 weeks before cardioversion
- Proceed with cardioversion (either immediate or delayed for possible spontaneous cardioversion).[1]
If the patient is not on anticoagulation, assess bleeding risk using the ORBIT score or the HAS-BLED score and then start anticoagulation pre-cardioversion as soon as possible.[3] [ ORBIT Bleeding Risk Score Opens in new window ] [ HAS-BLED Bleeding Risk Score Opens in new window ]
- Guidelines from the European Society of Cardiology (ESC) recommend use of the HAS-BLED score.[1] The National Institute for Health and Care Excellence (NICE) recommends use of ORBIT over HAS-BLED where possible.[3] In practice, either HAS-BLED or ORBIT is acceptable.
Choose an appropriate anticoagulant for the patient in line with your hospital protocols.
- Guidelines from the ESC recommend using a DOAC such as rivaroxaban, apixaban, edoxaban, or dabigatran; or a low molecular weight heparin (LMWH), such as enoxaparin; or unfractionated heparin.[1]
- Guidelines from NICE recommend using a LMWH or unfractionated heparin at initial presentation in this group.[3]
- Transition patients who are started on a LMWH or unfractionated heparin to a DOAC, such as rivaroxaban, apixaban, edoxaban, or dabigatran, or warfarin, when appropriate.[1] See Longer-term anticoagulation strategy below.

Primary options

apixaban: 2.5 to 5 mg orally twice daily

edoxaban: body weight <61 kg: 30 mg orally once daily; body weight ≥61 kg: 60 mg orally once daily

rivaroxaban: 20 mg orally once daily

dabigatran: 18-74 years of age: 150 mg orally twice daily; 75-79 years of age: 110-150 mg orally twice daily; ≥80 years of age: 110 mg orally twice daily

heparin: consult specialist for guidance on dose

enoxaparin: consult specialist for guidance on dose

Plus – treat underlying cause

Back

Plus –

treat underlying cause

Treatment recommended for ALL patients in selected patient group

In practice, refer to a cardiologist, any patient:
- Who is young and has suspected underlying structural heart disease
- With a pre-excitation syndrome such as Wolff-Parkinson-White syndrome.[53] See Wolff-Parkinson-White syndrome
- With valvular heart disease associated with AF
- With suspected heart failure.

Practical tip

Signs of stroke or heart failure may be subtle in some instances.

Plus – longer-term anticoagulation strategy

Back

Plus –

longer-term anticoagulation strategy

Treatment recommended for ALL patients in selected patient group

After cardioversion, continue anticoagulation. If the patient has been started on parenteral anticoagulation before cardioversion, transition them to an appropriate oral anticoagulant.

Use the CHA ₂DS ₂-VASc score to calculate stroke risk in all patients presenting with AF.[1][3] [ Atrial Fibrillation CHA(2)DS(2)-VASc Score for Stroke Risk Opens in new window ]

Consider oral anticoagulation for stroke prevention in men with a CHA ₂DS ₂-VASc score of 1 or more and women with a score of 2 or more.[1][3] In these groups, continue anticoagulation long-term.[1]
Guidelines from the European Society of Cardiology (ESC) give an additional, stronger recommendation for higher CHA ₂DS ₂-VASc scores; the ESC recommends commencing oral anticoagulation in AF patients with a CHA ₂DS ₂-VASc score of 2 or more in men and 3 or more in women.[1]

Assess the risk of a major bleed
Identify (and subsequently manage) modifiable risk factors for bleeding, such as uncontrolled hypertension, harmful alcohol consumption, labile international normalised ratio (INR; if the patient is on warfarin), concurrent use of medication (including antiplatelets, selective serotonin reuptake inhibitors, and non-steroidal anti-inflammatory drugs), and reversible causes of anaemia
Flag the ‘high bleeding risk’ patients for early (4 weeks as opposed to 4-6 months) review and follow-up.

Do not use bleeding risk scores to exclude anticoagulant treatment; a high score should not rule out anticoagulation.[64]

Bleeding risk is dynamic and requires regular re-assessment; it should not be based on a single one-off assessment.[65]

Practical tip

When indicated by the CHA ₂DS ₂-VASc score, start oral anticoagulation as soon as possible.[1]

Use a direct oral anticoagulant (DOAC) in preference to a vitamin K antagonist.[1][3] The ESC recommends DOACs in preference to a vitamin K antagonists.[1]

Discuss the options for anticoagulation with the patient and base the choice on their clinical features and preferences.[1][3]

Before starting anticoagulation treatment, specifically discuss the potential risks and benefits with the patient, as part of the shared decision-making process, explaining that:[3]
- For most people the benefit of anticoagulation outweighs the bleeding risk
- For people with an increased risk of bleeding the benefit of anticoagulation may not always outweigh the bleeding risk, and careful monitoring of bleeding risk is important.

If using a DOAC, choose one of apixaban, edoxaban, rivaroxaban, or dabigatran.[1] The choice of DOAC should be tailored to the person's clinical needs and preferences.[3]

DOACs have non-inferior efficacy and are possibly safer, particularly in terms of major bleeding, compared with warfarin.[71] [ ] [Evidence A] Unlike warfarin, DOACs don’t require laboratory anticoagulation monitoring.[72][73]

Do not offer aspirin monotherapy solely for stroke prevention to people with AF.[3]

A specialist may consider non-drug options in the presence of absolute contraindications to oral anticoagulants, including:[1]

Active serious bleeding (where the source should be identified and treated)
Associated comorbidities (e.g., severe thrombocytopenia <50 platelets/microlitre, severe anaemia under investigation, etc.)
A recent high-risk bleeding event such as intracranial haemorrhage.

Primary options

apixaban: 2.5 to 5 mg orally twice daily

edoxaban: body weight <61 kg: 30 mg orally once daily; body weight ≥61 kg: 60 mg orally once daily

rivaroxaban: 20 mg orally once daily

dabigatran: 18-74 years of age: 150 mg orally twice daily; 75-79 years of age: 110-150 mg orally twice daily; ≥80 years of age: 110 mg orally twice daily

Secondary options

warfarin: 5-10 mg orally once daily initially, adjust dose according to target INR

haemodynamically stable: onset ≥48 hours or uncertain

1st line – rate control

Back

1st line –

rate control

Use rate control to slow the patient’s heart rate in the presence of tachycardia.[1][2][3] In practice, do this while initially assessing the patient.

Rate control is often sufficient to improve AF-related symptoms.[1]
Bear in mind that there is very little in the way of robust evidence to inform the best type and intensity of rate control treatment.[1]

These are preferred first-line options as they have rapid onset of action and are effective for high sympathetic tone.[74][75][76][77][78]
Bear in mind that rate-limiting calcium-channel blockers are contraindicated in patients with heart failure with reduced ejection fraction (a common comorbidity).
Alternative drugs are available. Seek advice from a specialist on the best option for your individual patient.
- Consider digoxin monotherapy if the patient is sedentary (they do no or very little physical exercise) or if other rate-limiting drugs are not appropriate because of comorbidities or patient preferences.[3] In practice, this is also a good option for older patients.

If monotherapy does not control symptoms, and if continuing symptoms are thought to be due to poor ventricular rate control, consider combination therapy with any two of the following:[3]

A beta-blocker
Diltiazem
- Bear in mind that this is contraindicated in people with heart failure with reduced ejection fraction.[1] See Acute heart failure
Digoxin.

Practical tip

These drugs accelerate conduction down the accessory pathway to the ventricle putting the patient at risk of life-threatening arrhythmias, such as ventricular fibrillation and sudden death.[1]

Primary options

bisoprolol: 1.25 mg orally once daily initially, increase gradually according to response, maximum 20 mg/day

The European Society of Cardiology recommends a maximum intravenous dose of 20 mg/total dose, and an oral (immediate-release) dose of 25-100 mg twice daily.[1]

The European Society of Cardiology recommends a maximum dose of 300 micrograms/kg/minute.[1]

carvedilol: 3.125 mg orally twice daily initially, increase gradually according to response, maximum 50 mg/day (body weight <85 kg) or 100 mg/day (body weight >85 kg)

The European Society of Cardiology recommends a dose of 2.5 to 10 mg intravenously over 5 minutes. An extended-release oral formulation may be used if available.[1]

diltiazem: 60 mg orally (immediate-release) three times daily initially, increase gradually according to response, maximum 360 mg

Secondary options

digoxin: 0.75 to 1.5 mg orally given in divided doses over 24 hours for rapid digitalisation, followed by maintenance dose of 0.125 to 0.25 mg/day

These drug options and doses relate to a patient with no comorbidities.

Primary options

bisoprolol: 1.25 mg orally once daily initially, increase gradually according to response, maximum 20 mg/day

The European Society of Cardiology recommends a maximum intravenous dose of 20 mg/total dose, and an oral (immediate-release) dose of 25-100 mg twice daily.[1]

The European Society of Cardiology recommends a maximum dose of 300 micrograms/kg/minute.[1]

carvedilol: 3.125 mg orally twice daily initially, increase gradually according to response, maximum 50 mg/day (body weight <85 kg) or 100 mg/day (body weight >85 kg)

The European Society of Cardiology recommends a dose of 2.5 to 10 mg intravenously over 5 minutes. An extended-release oral formulation may be used if available.[1]

diltiazem: 60 mg orally (immediate-release) three times daily initially, increase gradually according to response, maximum 360 mg

Secondary options

digoxin: 0.75 to 1.5 mg orally given in divided doses over 24 hours for rapid digitalisation, followed by maintenance dose of 0.125 to 0.25 mg/day

Back to drug information with added comorbidities

Drug choice, dose and interactions may be affected by the patient's comorbidities. Check your local drug formulary.

Show drug information for a patient with no comorbidities

Primary options

bisoprolol

metoprolol

esmolol

carvedilol

verapamil

diltiazem

Secondary options

digoxin

Plus – elective electrical or pharmacological cardioversion

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Plus –

elective electrical or pharmacological cardioversion

Treatment recommended for ALL patients in selected patient group

If the onset of AF is 48 hours or more, or is uncertain:[1][3]

Make a plan for therapeutic anticoagulation for a minimum of 3 weeks followed by elective electrical or pharmacological cardioversion[1][3]
Continue therapeutic anticoagulation for 4 weeks after cardioversion (in patients without a need for long-term anticoagulation).[1][3]

Check the patient’s oral anticoagulation status.[1]

If the patient is already on therapeutic anticoagulation, proceed with cardioversion.[1]
If the patient is not on anticoagulation, assess bleeding risk using the ORBIT score or the HAS-BLED score and then start anticoagulation pre-cardioversion as soon as possible.[3] [ ORBIT Bleeding Risk Score Opens in new window ] [ HAS-BLED Bleeding Risk Score Opens in new window ]
- Guidelines from the European Society of Cardiology recommend use of the HAS-BLED score.[1] The National Institute for Health and Care Excellence (NICE) recommends use of ORBIT over HAS-BLED where possible.[3] In practice, either HAS-BLED or ORBIT is acceptable.
Beyond 4 weeks, base decisions about long-term anticoagulation on associated stroke risk factors, as per the patient’s CHA ₂DS ₂-VASc score.[1][3][34] [ Atrial Fibrillation CHA(2)DS(2)-VASc Score for Stroke Risk Opens in new window ] See Longer term anticoagulation strategy below.

Choose either pharmacological or electrical cardioversion depending on clinical circumstances, patient preferences, and resources, to reduce symptoms.[1][3]

Electrical cardioversion is achieved with synchronised direct current (DC) cardioversion. Pharmacological cardioversion uses an anti-arrhythmic drug, selected according to the patient’s history and condition.[1]
In haemodynamically stable patients, the decision to use electrical or pharmacological cardioversion will depend on local expertise, facilities and drugs available, the availability of a suitable clinician to administer sedation if electric cardioversion is selected, and patient preference.

Electrical cardioversion

Seek anaesthetic support to sedate the patient before DC cardioversion.[1]

Intravenous sedation should not be administered in the fed state as this increases the risk of aspiration. The anaesthetist will also be able to advise how long the patient should be fasting for safe sedation.

Record and store an ECG rhythm strip during and immediately after shock delivery.

Continuously monitor the patient’s blood pressure and oximetry during the procedure.[1][67]

Practical tip

Ensure the defibrillator is synchronised and that it remains synchronised between shocks.

If initial attempts at DC cardioversion fail, ensure there is good skin-to-electrode contact with the pads in the anteroposterior position.

Pharmacological cardioversion

Bear in mind that pharmacological cardioversion requires continuous medical supervision and ECG monitoring, regardless of the drug used, to detect a pro-arrhythmic event.[79]

In practice, this will usually be undertaken in a cardiac monitoring bed (e.g., in the cardiac care unit or a resuscitation bed in the accident and emergency department).

Use an anti-arrhythmic drug, selected according to the patient’s history and the overall clinical picture.[1][3] NICE recommends offering:[3]

A choice of flecainide or amiodarone to people with no evidence of structural or ischaemic heart disease
or
Amiodarone to people with evidence of structural heart disease
- You will need a large-bore cannula for amiodarone.

Other anti-arrhythmics used outside of the UK include:[1]

Vernakalant – although available in the UK, it is rarely used
Ibutilide – not available in the UK.

Seek specialist opinion from a cardiologist if you are unsure about which drug to use.

Do not use sotalol.[3]

Using a sodium-channel blocker such as flecainide without an AV nodal blocking agent can convert to a slower atrial flutter rhythm, which allows the AV node to conduct in a 1:1 fashion and paradoxically results in faster ventricular response.[1]
Although this can occur in the acute situation of pharmacological cardioversion it is more important when considering these drugs for longer-term management to prevent recurrent AF.
If in doubt, seek specialist cardiology advice.

Primary options

flecainide: 200-300 mg orally as a single dose

The European Society of Cardiology recommends intravenous flecainide as a treatment option at a dose of 2 mg/kg intravenously over 10 minutes; however, this formulation is not available in the UK.[1]

amiodarone: 5-7 mg/kg intravenously over 1-2 hours, followed by 50 mg/hour intravenous infusion, maximum 1200 mg/day

Consider – pre-cardioversion anticoagulation

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Consider –

pre-cardioversion anticoagulation

Additional treatment recommended for SOME patients in selected patient group

Check the patient’s oral anticoagulation status.[1]

If the patient is already on therapeutic anticoagulation, proceed with cardioversion.[1]
If the patient is not on anticoagulation, assess bleeding risk using the ORBIT score or the HAS-BLED score and then start anticoagulation pre-cardioversion as soon as possible.[3] [ ORBIT Bleeding Risk Score Opens in new window ] [ HAS-BLED Bleeding Risk Score Opens in new window ]
- Guidelines from the European Society of Cardiology (ESC) recommend use of the HAS-BLED score.[1] The National Institute for Health and Care Excellence (NICE) recommends use of ORBIT over HAS-BLED where possible.[3] In practice, either HAS-BLED or ORBIT is acceptable.
Choose an appropriate anticoagulant for the patient in line with your hospital protocols.
- Guidelines from the ESC recommend using a direct oral anticoagulant (DOAC) such as rivaroxaban, apixaban, edoxaban, or dabigatran; or a low molecular weight heparin (LMWH), such as enoxaparin; or unfractionated heparin.[1]
- Guidelines from NICE recommend using a LMWH or unfractionated heparin at initial presentation in this group.[3]
- Transition patients who are started on a LMWH or unfractionated heparin to a DOAC, such as rivaroxaban, apixaban, edoxaban, or dabigatran, or warfarin, when appropriate.[1] See Longer-term anticoagulation strategy below.

Primary options

apixaban: 2.5 to 5 mg orally twice daily

edoxaban: body weight <61 kg: 30 mg orally once daily; body weight ≥61 kg: 60 mg orally once daily

rivaroxaban: 20 mg orally once daily

dabigatran: 18-74 years of age: 150 mg orally twice daily; 75-79 years of age: 110-150 mg orally twice daily; ≥80 years of age: 110 mg orally twice daily

heparin: consult specialist for guidance on dose

enoxaparin: consult specialist for guidance on dose

Plus – treat underlying cause

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Plus –

treat underlying cause

Treatment recommended for ALL patients in selected patient group

In practice, refer to a cardiologist, any patient:
- Who is young and has suspected underlying structural heart disease
- With a pre-excitation syndrome such as Wolff-Parkinson-White syndrome.[53] See Wolff-Parkinson-White syndrome
- With valvular heart disease associated with AF
- With suspected heart failure.

Practical tip

Signs of stroke or heart failure may be subtle in some instances.

Plus – longer-term anticoagulation strategy

Back

Plus –

longer-term anticoagulation strategy

Treatment recommended for ALL patients in selected patient group

After cardioversion, continue anticoagulation. If the patient has been started on parenteral anticoagulation before cardioversion, transition them to an appropriate oral anticoagulant.

Use the CHA ₂DS ₂-VASc score to calculate stroke risk in all patients presenting with AF.[1][3] [ Atrial Fibrillation CHA(2)DS(2)-VASc Score for Stroke Risk Opens in new window ]

Consider oral anticoagulation for stroke prevention in men with a CHA ₂DS ₂-VASc score of 1 or more and women with a score of 2 or more.[1][3] In these groups, continue anticoagulation long-term.[1]
Guidelines from the European Society of Cardiology (ESC) give an additional, stronger recommendation for higher CHA ₂DS ₂-VASc scores; the ESC recommends commencing oral anticoagulation in AF patients with a CHA ₂DS ₂-VASc score of 2 or more in men and 3 or more in women.[1]

If you are considering anticoagulation, use the ORBIT score or HAS-BLED score to:[1][3][34][36] [ ORBIT Bleeding Risk Score Opens in new window ] [ HAS-BLED Bleeding Risk Score Opens in new window ]

Assess the risk of a major bleed
Identify (and subsequently manage) modifiable risk factors for bleeding, such as uncontrolled hypertension, harmful alcohol consumption, labile international normalised ratio (INR; if the patient is on warfarin), and concurrent use of aspirin or a non-steroidal anti-inflammatory drug
Flag the ‘high bleeding risk’ patients for early (4 weeks as opposed to 4-6 months) review and follow-up.

Do not use bleeding risk scores to exclude anticoagulant treatment; a high score should not rule out anticoagulation.[64]

Bleeding risk is dynamic and requires regular re-assessment; it should not be based on a single one-off assessment.[65]

Practical tip

When indicated by the CHA ₂DS ₂-VASc score, start oral anticoagulation as soon as possible.[1]

Use a direct oral anticoagulant (DOAC) in preference to a vitamin K antagonist.[1][3] The ESC recommends DOACs in preference to a vitamin K antagonists.[1]

Discuss the options for anticoagulation with the patient and base the choice on their clinical features and preferences.[1][3]

Before starting anticoagulation treatment, specifically discuss the potential risks and benefits with the patient, as part of the shared decision-making process, explaining that:[3]
- For most people the benefit of anticoagulation outweighs the bleeding risk
- For people with an increased risk of bleeding the benefit of anticoagulation may not always outweigh the bleeding risk, and careful monitoring of bleeding risk is important.

If using a DOAC, choose one of apixaban, edoxaban, rivaroxaban, or dabigatran.[1] The choice of DOAC should be tailored to the person's clinical needs and preferences.[3]

DOACs have non-inferior efficacy and are possibly safer, particularly in terms of major bleeding, compared with warfarin.[71] [ ] [Evidence A] Unlike warfarin, DOACs don’t require laboratory anticoagulation monitoring.[72][73]

Do not offer aspirin monotherapy solely for stroke prevention to people with AF.[3]

A specialist may consider non-drug options in the presence of absolute contraindications to oral anticoagulants, including:[1]

Active serious bleeding (where the source should be identified and treated)
Associated comorbidities (e.g., severe thrombocytopenia <50 platelets/microlitre, severe anaemia under investigation, etc.)
A recent high-risk bleeding event such as intracranial haemorrhage.

Primary options

apixaban: 2.5 to 5 mg orally twice daily

edoxaban: body weight <61 kg: 30 mg orally once daily; body weight ≥61 kg: 60 mg orally once daily

rivaroxaban: 20 mg orally once daily

dabigatran: 18-74 years of age: 150 mg orally twice daily; 75-79 years of age: 110-150 mg orally twice daily; ≥80 years of age: 110 mg orally twice daily

Secondary options

warfarin: 5-10 mg orally once daily initially, adjust dose according to target INR

ONGOING

post-stabilisation

1st line – specialist referral for follow-up

Plus – advice on lifestyle, cardiovascular risk factors, and comorbidities

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Plus –

advice on lifestyle, cardiovascular risk factors, and comorbidities

Treatment recommended for ALL patients in selected patient group

Identify unhealthy lifestyle factors and give the patient advice on these to help prevent recurrence.[1] Focus, where relevant, on the following factors.

Physical activity: encourage the patient to undertake moderate-intensity exercise and remain physically active.[1] Advise the patient to avoid excessive endurance exercise (e.g., marathons and long-distance triathlons), especially if they are over 50 years old.[1]
Weight loss with comprehensive management of concomitant cardiovascular risk factors: maintaining a healthy weight may reduce blood pressure, dyslipidaemia, and risk of developing type 2 diabetes mellitus, therefore improving the patient’s overall cardiovascular risk profile.[1]
Alcohol intake reduction: regular heavier alcohol consumption (>14 units/week) is associated with an increased risk of AF.[23] Alcohol abstinence has been shown to reduce arrhythmia recurrence in regular drinkers with AF.[1]

Work with the patient to identify strategies for comprehensive risk-factor modification and interventions targeting underlying conditions that may apply, in particular:[1]

Hypertension
- See Essential hypertension
Heart failure
- See Acute heart failure
Coronary artery disease
- See Stable ischaemic heart disease
Diabetes mellitus
- See Overview of diabetes
Obstructive sleep apnoea
- See Obstructive sleep apnoea in adults.

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New-onset atrial fibrillation

Treatment algorithm

haemodynamically unstable

emergency electrical cardioversion

Practical tip

pre-cardioversion anticoagulation

Primary options

These drug options and doses relate to a patient with no comorbidities.

Primary options

Drug choice, dose and interactions may be affected by the patient's comorbidities. Check your local drug formulary.

Primary options

treat underlying cause

Practical tip

amiodarone

Primary options

These drug options and doses relate to a patient with no comorbidities.

Primary options

Drug choice, dose and interactions may be affected by the patient's comorbidities. Check your local drug formulary.

Primary options

longer-term anticoagulation strategy

Practical tip

Practical tip

Primary options

Secondary options

These drug options and doses relate to a patient with no comorbidities.

Primary options

Secondary options

Drug choice, dose and interactions may be affected by the patient's comorbidities. Check your local drug formulary.

Primary options

Secondary options

haemodynamically stable: onset <48 hours

rate control

Practical tip

Primary options

Secondary options

These drug options and doses relate to a patient with no comorbidities.

Primary options

Secondary options

Drug choice, dose and interactions may be affected by the patient's comorbidities. Check your local drug formulary.

Primary options

Secondary options

consider early rhythm control

Practical tip

Electrical cardioversion

Practical tip

Pharmacological cardioversion

Primary options

These drug options and doses relate to a patient with no comorbidities.

Primary options

Drug choice, dose and interactions may be affected by the patient's comorbidities. Check your local drug formulary.

Primary options

pre-cardioversion anticoagulation

Primary options

These drug options and doses relate to a patient with no comorbidities.

Primary options

Drug choice, dose and interactions may be affected by the patient's comorbidities. Check your local drug formulary.

Primary options

treat underlying cause

Practical tip

longer-term anticoagulation strategy

Practical tip

Practical tip

Primary options

Secondary options

These drug options and doses relate to a patient with no comorbidities.

Primary options

Secondary options

Drug choice, dose and interactions may be affected by the patient's comorbidities. Check your local drug formulary.

Primary options

Secondary options

haemodynamically stable: onset ≥48 hours or uncertain

rate control

Practical tip

Primary options

Secondary options

These drug options and doses relate to a patient with no comorbidities.

Primary options

Secondary options

Drug choice, dose and interactions may be affected by the patient's comorbidities. Check your local drug formulary.

Primary options