Atrial fibrillation

June 2006

Changing clinical practice

NICE guidelines are based on the best available evidence

The Department of Health asks NHS organisations to work towards implementing guidelines

Compliance will be monitored by the Healthcare Commission

Atrial fibrillation

Atrial fibrillation (AF) is an atrial tachyarrhythmia characterised by predominantly uncoordinated atrial activation with consequent deterioration of atrial mechanical function

On the ECG, there is an absence of consistent P waves; instead there are rapid oscillations or fibrillatory waves that vary in size, shape and timing

Reproduced by kind permission of Ashford and St. Peter’s Hospitals NHS Trust

Several causes of AF

Often caused by co-existing medical conditions – both cardiac and non-cardiac

Associated with increasing age, hypertension, heart failure, diabetes mellitus and valve disease

Dietary and lifestyle factors have also been associated with AF

Common after surgery, especially cardiothoracic operations

Terminology Clinical features Pattern

Initial event (first detected episode)

Symptomatic Asymptomatic Onset unknown

May or may nor reoccur

Paroxysmal Spontaneous termination <7 days and most often <48 hours

Recurrent

Persistent Not self-terminating Lasting >7 days or prior cardioversion

Recurrent

Permanent (‘accepted’)

Not terminated Terminated but relapsed No cardioversion attempt

Established

Classification of AF

Need for this guideline

AF is a significant risk factor for mortality, as well as stroke and other morbidities

AF is the commonest sustained cardiac arrhythmia

Too often, AF is detected only after the patient presents with serious complications of AF

AF incidence and prevalence increase with increasing age. With an increasingly elderly population, AF is likely to become more common

Commonest cardiac arrhythmia

The prevalence of AF roughly doubles with each decade of age: from 0.5% at age 50–59 years to almost 9.0% at age 80–90 years

Present in 3–6% of acute hospital admissions

Prevalence of 4.7% of people aged 65 years or over in general practice

Prevalence of AF in the Renfrew-Paisley study

Cohort of men and women aged 45–64 years (n = 15,406)

Reproduced with permission of the BMJ Publishing Group from Stewart S et al, Heart 2001: 86:516-21

What needs to happen

Opportunistic/targeted case detection including taking a manual pulse to detect AF

Accurate diagnosis of AF using an ECG

Further investigations and clinical assessment, including risk stratification for stroke/thromboembolism

Development of a management plan – rate-control, rhythm-control or referral

Antithrombotic therapy as appropriate

Follow-up and review

Case detection

Assessment

Rate- contro

l

Rhythm-

control

Referral

Follow-up

Follow-up

OR

AF care pathway

Primary/secondary/emergency care

Primary/secondary care

Secondary/tertiary care

The management and presentation of AF involves all healthcare settings

Case detection

Assessment

Rate- contro

l

Rhythm-

control

Referral

Follow-up

Follow-up

OR

Key priority – detection and diagnosis

An ECG should be performedin all patients, whether symptomatic or not, in whom AF is suspected because an irregular pulse has been detected

Suggested actions

People with undiagnosed AF can receive treatment sooner if opportunistic case finding is undertaken using manual pulse palpation

Promote opportunistic case detection and targeting of patients at increased risk:

• Primary care: appropriate long-term condition registers, people aged >65 years, flu vaccination programme

• Secondary care: A&E, outpatient clinics and wards, especially care of the elderly

Suggested actionsRemember to use ECG to confirm diagnosis and the routine recording of ECG results

Review access to diagnostics – irrespective of how services are structured locally, easy access and rapid reporting are essential

Remember incentives and encourage practices to establish and maintain a practice-based AF register in line with the QOF 06/07 AF indicators

Consider establishing a PCT-led, community-based, rapid-access arrhythmia clinic

Case detection

Assessment

Rate- control

Rhythm-

control

Referral

Follow-up

Follow-up

OR

• Some patients with persistent AF will satisfycriteria for either an initialrate- or rhythm-control strategy• Indications for each option are not mutuallyexclusive• Involve the patient in the treatment decision• Take comorbidities intoaccount • Antithrombotic therapyshould always be used

Key priority – choosing the most effective treatment

Treatment for persistent AF

Two main treatment strategies:

Rate-control involves the use of chronotropic drugs or electrophysiological/surgical interventions

Rhythm-control involves the use of electrical or pharmacological cardioversion for persistent AF, or suppression of recurrent (e.g. paroxysmal) AF

There is still the need for appropriate antithrombotic therapy if a rhythm-control strategy is chosen

Rate-control strategyTry rate control first for patients with persistent AF:

• over 65

• with coronary artery disease

• with contraindications to antiarrhythmic drugs

• unsuitable for cardioversion

• without congestive heart failure

Rhythm-control strategyTry rhythm-control first for patients with persistent AF:

• who are symptomatic

• who are younger

• presenting for the first time with lone AF

• secondary to a treated/corrected precipitant

• with congestive heart failure

Suggested actions

Liaise with your local cardiac network – benefit from shared learning and support. For example, some areas have established a primary care rapid access arrhythmia clinic and the provision of an arrhythmia care co-ordinator or an arrhythmia nurse specialist

Provide awareness raising and education sessions for healthcare professionals – don’t forget to include out-of-hours services

Develop, promote and disseminate quality patient information and decision aids for clinicians

Case detection

Assessment

Rate- contro

l

Rhythm-

control

Referral

Follow-up

Follow-up

OR

• Use the ‘stroke risk stratification algorithm’ to assess risk of stroke andthromboembolism• Use antithrombotic therapy as appropriate• Initiate antithrombotictherapy with minimal delay in patients newly diagnosed with AF

Key priority – assess for risk of stroke and thromboembolism

Determine stroke/thromboembolic risk

High risk:

• Previous ischaemic stroke/TIA or thromboembolic event

• Age >75 with hypertension, diabetes or vascular disease

• Clinical evidence of valve disease, heart failure, or impaired left ventricular function on echocardiography

Moderate risk:

• Age >65 with no high risk factors

• Age <75 with hypertension, diabetes or vascular disease

Low risk:

• Age <65 with no moderate or high risk factors

Patients with AF

Determine stroke/thromboembolic risk

High risk

Moderate risk

Low risk

Consider anticoagulationConsider anticoagulation

or aspirinAspirin 75 to 300 mg/day

if no contraindications

Contraindications towarfarin?

Warfarin, target INR = 2.5(range 2.0 to 3.0)

Reassess risk stratificationwhenever individual risk

factors are reviewed

NOYES

Patients with AF

Anticoagulation

Assessment of bleeding risk should be part of the clinical assessment of AF patients prior to starting anticoagulation

Antithrombotic benefits and potential bleeding risks of long-term coagulation should be explained and discussed with the patient

Aim for a target INR of between 2.0 and 3.0

Forms of monitoring include point of care or near patient testing and patient self-monitoring

Suggested actionsReview anticoagulation services locally

Remember incentives for anticoagulation monitoring and near patient testing, e.g. QOF 06/07 and National Enhanced Services

Provide awareness raising and education sessions - emphasise stroke prevention and promote the use of the stroke risk stratification algorithm

Consider integrating risk stratification into computerised patient management software

Ensure provision of quality patient information

Case detection

Assessment

Rate- contro

l

Rhythm-

control

Referral

Follow-up

Follow-up

OR

Key priority – optimise pharmacological management

In patients with permanent AF, who needtreatment for rate-control:

– beta-blockers or rate-limiting calcium antagonists should be the preferred initial monotherapyin all patients

– digoxin should only be considered as monotherapy in predominantly sedentary patients

Treatment for permanent AF

The aim of heart rate control is to:

• minimise symptoms associated with excessive heart rates

• prevent tachycardia-associated cardiomyopathy

Digoxin monotherapy should only be useful for older, sedentary patients

Perform a risk–benefit assessment to inform the decision of whether or not to give antithrombotic therapy

Suggested actions

Work with local Drugs and Therapeutics Committees and prescribing advisors to review and update prescribing formularies

Emphasise clinically effective alternatives to digoxin to PCT prescribing advisors and prescribing leads

Provide awareness raising and updating sessions for local primary and secondary care healthcare professionals

Cardioversion

Cardioversion is performed as part of a rhythm-control treatment strategy

There are two types of cardioversion: electrical (ECV) and pharmacological (PCV)

Cardioversion of AF is associated with increased risk of stroke in the absence of antithrombotic therapy

Not all attempts at ECV or PCV are successful

Patient choice is important

Treatment for paroxysmal AF

Patients with paroxysmal AF can be highly symptomatic

Three main aims of treatment for paroxysmal AF are to:• suppress paroxysms of AF and maintain sinus rhythm• control heart rate during paroxysms of AF• prevent complications

Treatment strategies include out-of-hospital initiation of antiarrhythmic drugs: ‘pill in the pocket’ approach

Patients with paroxysmal AF carry the same risks of stroke and thromboembolism as those with persistent AF

Acute-onset AF

Acute-onset AF requires immediate hospitalisation and urgent intervention

Those at highest risk have a ventricular rate greater than 150 bpm, ongoing chest pain or critical perfusion

Follow-up and referral

Follow-up after cardioversion should take place at 1 month, and the frequency of subsequent reviews should be tailored to the patient

Reassess the need for anticoagulation at each review

Referral for further specialist intervention should be considered in patients:

• in whom pharmacological therapy has failed

• with lone AF

• with ECG evidence of any underlying electrophysiological disorder

Costs and savings

Main elements identified as:

• costs incurred due to increased use of ECG to confirm diagnosis

• increases in the use of anticoagulants in those with AF, which includes: costs of additional anticoagulant services and of major bleeds incurred, and savings resulting from strokes and deaths avoided

Access tools online

Costing tools

•costing report•costing template

Audit criteria

Implementation advice

Available from: www.nice.org.uk/cg036

Access the guideline online

Quick reference guide – a summary www.nice.org.uk/CG036quickrefguide

NICE guideline – all of the recommendations www.nice.org.uk/CG036niceguideline

Full guideline – all of the evidence and rationale www.nice.org.uk/CG036fullguideline

Information for the public – a plain English version www.nice.org.uk/CG036publicinfo