Surveillance decision

Surveillance decision

We will plan an update of the guideline on atrial fibrillation (AF). The update will focus on:

  • diagnosis and assessment

  • assessment of stroke and bleeding risks

  • interventions to prevent stroke

  • rate and rhythm control

  • prevention and management of postoperative atrial fibrillation.

An extension to the scope will be needed to incorporate:

  • case detection of atrial fibrillation

  • short term use of antiarrhythmic drugs following ablation

  • the use of statins to prevent postoperative atrial fibrillation.

During surveillance editorial or factual corrections were identified. Details are included in appendix A: summary of evidence from surveillance.

Reason for the decision

Assessing the evidence

We found 250 studies through surveillance of this guideline.

Evidence that could affect recommendations was identified. Topic experts, including those who helped to develop the guideline, advised us about whether the following sections of the guideline should be updated and any new sections added:

Diagnosis and assessment
  • Identification and assessment: presenting symptoms/pulse palpitation

Population screening falls within the remit of the National Screening committee (NSC); the NSC considered AF in 2014 and did not recommend screening although this is scheduled for review in 2018.

Evidence from a systematic review identified during the surveillance review indicates that case detection in high risk AF patients, using an opportunistic approach, is as effective as population screening but at a significantly lower cost. Topic experts and NSC feedback indicated that detection of AF in high risk patients is potentially within the remit of NICE and that a new question in the guideline could be appropriate to include multiple components. These include:

  • Targeting at risk individuals with other pathologies predisposing to AF, such as related cardiovascular conditions.

  • The optimal means of detection including new technological developments, such as through pulse rhythm checks and with the use of the new handheld ECG monitors.

  • Monitoring for secondary prevention in patients who have already had a stroke. New evidence indicates that insertable cardiac monitors (ICMs), including loop recorders, are a cost-effective diagnostic tool for the prevention of recurrent stroke in patients with cryptogenic stroke. The guideline does not make recommendations for the use of ICMs.

There is therefore a potential impact on the guideline to consider detection of AF based on high risk assessment.

Decision: This review question should be added.

  • In patients with suspected AF based on an irregular pulse, how accurate is an ECG in diagnosing AF?

NICE's guideline on AF does not make recommendations on ECG-interpreting software. The new systematic review evidence indicates that the use of automated ECG-interpreting software may enable GPs to more accurately interpret 12 lead ECGs and to rule out AF in primary care. However, its sensitivity appears to be similar to interpretation by healthcare professionals and further evidence may therefore be required to establish a definite impact on the guideline. The lack of conclusive evidence was also confirmed by topic expert feedback.

Decision: This question should not be updated.

  • In patients with suspected intermittent AF, how effective is ambulatory ECG rather than event ECG in diagnosing AF?

New evidence and topic expert feedback highlighted that ICMs, including loop recorders, are a cost-effective diagnostic tool for the prevention of recurrent stroke in patients with cryptogenic stroke. The guideline does not make recommendations for the use of ICMs. Topic experts advised that the potential impact lies in the question on detection and that this question does not require updating.

Decision: This question should not be updated.

Assessment of stroke and bleeding risks
  • What is the most clinically and cost-effective risk stratification tool for stroke or thromboembolic events in people with AF?

The guideline recommends the use of CHA2DS2-VASc stroke risk score to assess stroke risk in AF, atrial flutter, or a continuing risk of arrhythmia recurrence after cardioversion back to sinus rhythm. The collective new evidence and topic expert feedback indicates that other new and emerging risk scores including Atria, ABC, and QStroke may perform more accurately than CHA2DS2-VASc and that all risk scores should be reviewed.

The review of these tools should take into account the following factors as indicated by new evidence and topic expert feedback:

  • The complexity of the tools, including the number of variables and potential further simplification of CHA2DS2-VASc to focus on a single risk factor, with age being the most important.

  • The implementation challenge of changing recommended risk calculators and the resulting need for education and training.

  • Sample size and setting of the validation studies, which should be representative of the NHS in England and Wales.

  • Appropriate risk assessment for specific sub-groups, such as patients who have undergone percutaneous coronary intervention and people of Asian family origin, with new evidence indicating that a modified version of CHA2DS2-VASc may be more useful for people from an Asian family origin.

  • Patient involvement in shared decision making. Anticoagulation was highlighted by topic experts as a preference sensitive decision, with large variations in patient preference. A simple dichotomous risk score may not always be informative enough for patients.

Decision: This review question should be updated.

  • What is the clinical and cost effectiveness of HAS-BLED compared to other tools in assessing bleeding risk in people with AF?

Topic experts noted that there was considerable debate about the use of the HAS-BLED score to assess the risk of intervention for stroke prevention during the development of the guideline.

Subsequent clinical education experience has indicated that recommendation 1.4.2 has not been well implemented and in some areas seems to be obstructing appropriate intervention to reduce stroke risk. Topic experts highlighted uncertainty around the usefulness of HAS-BLED, referring to recent European Society of Cardiology guidelines on AF, which list bleeding risk factors that are considered to be more inclusive than HAS-BLED. Consequently it was felt that HAS-BLED's position in the guideline should be reviewed.

However, additional topic expert feedback stated that HAS-BLED has value as a simple score for bleeding risk assessment which also focuses on identification of high risk patients for review and follow-up, and which highlights the potentially reversible bleeding risk factors.

New evidence and topic expert feedback indicates that HAS-BLED may not be superior to other bleeding risk scores, including Atria, ABC, and QBleed. There is therefore a potential impact on recommendation 1.4.2 to review the different risk scores, taking into account the following factors emerging from the collective evidence and topic expert feedback:

  • The need for the recommendation to be restructured to prioritise minimising bleeding risk over using any specific tool. The variable risk in sub-groups such as people undergoing percutaneous coronary intervention and people over 80 years old should also be considered.

  • Implementation and education to aid GPs' understanding of how the risk tool and score should be used.

  • The complexity of the tools, including the number of included variables and the potential recalibration of HAS-BLED counting two points for a haemorrhagic stroke.

Decision: This review question should be updated.

Interventions to prevent stroke
  • What is the most clinical and cost-effective antithrombotic therapy for stroke prevention in people with AF?

Since the publication of the guideline, another anticoagulant has become available, edoxaban. Although this is covered by NICE technology appraisal guidance 355 on edoxaban for preventing stroke and systemic embolism in people with non-valvular atrial fibrillation (September 2015), it is not included in the guideline. Topic experts advised that the recommendations from the technology appraisal should be incorporated into the guideline.

Topic expert feedback highlighted the need to provide contextual guidance on NOACs covered by the NICE technology appraisals that have been incorporated into NICE's guideline on AF. This was considered necessary to aid decision making on the choice of anticoagulant in specific patient groups, and on switching between warfarin and NOAC treatments. However, the highly diverse range of factors informing the choice of anticoagulant, including heterogeneous patient groups, are beyond the scope of the guideline. NICE implementation teams will explore methods and tools to aid treatment choices.

In the light of safety concerns about the use of warfarin in patients with AF who experience a head injury, topic experts indicated that the guideline should cross refer to NICE guideline on head injury. Additionally, topic expert feedback advised that the recommendation should be broadened from warfarin to incorporate any anticoagulant.

Topic experts noted that the course of action in the context of AF and an indication for dual antiplatelet therapy is frequently encountered in clinical practice. This includes people who have had a myocardial infarction and who also have AF, for whom anticoagulation is needed in addition to dual antiplatelet therapy. This issue is only briefly considered in the full version of the guideline, because most of the applicable studies had already been considered in NICE's guideline on myocardial infarction. However, topic experts stressed that, given the importance of this issue, it should be addressed in an update of the guideline. A cross reference to NICE's guideline on myocardial infarction will be incorporated.

Decision: This review question should be updated.

  • What is the clinical and cost effectiveness of left atrial appendage occlusion (LAAO) compared to anti-thrombotic therapy in the prevention of stroke in people with AF?

New systematic review and randomised controlled trial (RCT) evidence indicates that LAAO is non-inferior to oral anticoagulation without LAAO, with comparable efficacy and safety.

Topic expert feedback indicated that, although the guideline recommends LAAO in situations where other forms of anticoagulation were contraindicated, there was no formal cost effectiveness assessment as part of the guideline development. Topic experts noted that in recent years, provision has been made for a limited number of patients to undergo LAAO through NHS England's Commissioning through Evaluation scheme. This finished in November 2016 and there is no longer a funding source for this procedure. A clearer identification of patients in whom the procedure is thought to be cost effective was considered to be important in an update of the question.

New evidence and topic expert feedback indicates that LAAO with the Watchman device is a non-inferior alternative to warfarin for stroke prevention in patients with AF, but cautious use is essential given safety concerns over complications. Further expert feedback highlighted that surgical closure should be considered as an alternative intervention, using a thoracoscopic technique with the AtriClip exclusion system, which is always occlusive. A review of the comparable efficacy between the LAAO devices, surgical closure and NOACs is therefore necessary, including a cost effectiveness analysis.

Decision: This review question should be updated.

  • What is the clinical and cost effectiveness of using different rate control drug strategies in the pharmacological management of atrial fibrillation?

New evidence and topic expert feedback indicates that in patients with concomitant heart failure and AF, beta-blocker therapy may not reduce all-cause mortality. NICE's guideline on AF advises that the choice of drug, either a beta-blocker or calcium channel blocker, should be based on the person's symptoms, heart rate, comorbidities and preferences. The new evidence is broadly consistent with basing the choice on comorbidities, but the recommendation may need to be revised to omit beta-blockers as an option for initial monotherapy in patients with comorbid AF and heart failure. The new evidence is stronger than the single trial reviewed by the guideline committee relating to beta-blockers in this sub-population. There is therefore a potential impact on the guideline to amend the recommendation.

Decision: This review question should be updated.

Rate and rhythm control
  • What is the clinical and cost effectiveness of catheter ablation compared to non-ablation therapies in people with atrial fibrillation?

The collective new evidence indicates that radiofrequency catheter ablation in particular, and possibly cryoballoon ablation, may be more effective than anti-arrhythmic drug (AAD) management in reducing AF in both paroxysmal and persistent AF. The evidence also suggests that the acute complication rate of catheter ablation may have decreased over time and could be comparable to that of medical therapy.

NICE's guideline on AF advises that left atrial catheter ablation should be offered to people with paroxysmal AF, and considered for people with persistent AF, if drug treatment has failed to control symptoms of AF or is unsuitable. It was unclear at the time of guideline development whether there was a difference between left atrial catheter ablation and medical therapies in reducing mortality, stroke, hospitalisation for heart failure and embolic complications in AF patients. However, the new evidence indicates that the incidence rates of all-cause mortality and stroke may be comparable between catheter ablation and AAD therapy, and there is therefore a potential impact on the recommendation. Topic experts noted that the review should also include a comparison between surgical and catheter ablation, and cryoablation as an alternative to radiofrequency ablation.

Topic expert feedback further highlighted that there is increasing evidence for a staged hybrid approach for people with long standing persistent AF, which is the subject of the ongoing trials CASA AF, CEASE AF and DEEP. These will be monitored by the surveillance team for consideration in a future review of the guideline.

Decision: This review question should be updated.

Prevention and management of postoperative atrial fibrillation
  • What is the best treatment strategy (rate or rhythm control or no treatment) for patients with postoperative AF?

New evidence and topic expert feedback indicates that strategies for rate control and rhythm control achieved similar outcomes in treating postoperative AF (POAF) and that neither treatment strategy showed a net clinical advantage over the other. There is a potential impact on the guideline to review the advice to offer a rhythm‑control strategy as the initial management option for the treatment of POAF following cardiothoracic surgery, unless contraindicated.

Decision: This review question should be updated.

  • New review question – What is the effectiveness of statins in the prevention of postoperative atrial fibrillation?

New systematic review evidence indicates that perioperative statin therapy, particularly atorvastatin, may decrease the risk of POAF in patients undergoing cardiac surgery. The evidence appears to be strongest in patients undergoing isolated coronary artery bypass grafting. Topic expert feedback noted that statins are used in most patients undergoing cardiac surgery and that their anti-inflammatory effects are considered to be beneficial for preventing POAF and the inflammatory responses to cardiopulmonary bypass. The guideline does not make recommendations on the use of statins, and there is therefore a potential need to include the new question in an update of the guideline. Expert feedback also advised a cross referral from the guideline to NICE's guideline on cardiovascular disease: risk assessment and reduction, including lipid modification, to assess cardiovascular risk as advised, before discussing with patients the use of statins for the prevention of POAF.

Decision: This review question should be added.

Short term use of antiarrhythmic drugs following ablation
  • New review question – What is the effectiveness of short term antiarrhythmic drugs following ablation for the prevention of AF recurrence?

New evidence indicates that the use of AADs following catheter ablation may reduce the incidence of early recurrent atrial tachyarrhythmias within 3 months, but did not prevent late recurrence of AF beyond 3 months of ablation. NICE's guideline on AF advises against the use of amiodarone for long term rate control but does not make specific recommendations relating to AADs post ablation. There is a potential need to include the new question in an update of the guideline.

Decision: This review question should be added.

We also found evidence that supports current recommendations on:

  • echocardiography

  • educational and behavioural interventions

  • referral for specialised management

  • systematic monitoring

  • transoesophageal echocardiography (TOE)-guided cardioversion

  • drug treatment for long-term rhythm control

  • surgical ablation compared to catheter ablation

  • antiarrhythmic drugs to prevent postoperative AF.

We did not find any evidence related to the recommendations on:

  • clinical and cost-effective means of (excluding ablation) restoring sinus rhythm

  • surgical ablation compared to non-ablation.

For any evidence relating to published or ongoing NICE technology appraisals, the guideline surveillance review deferred to the technology appraisal decision. This included technology appraisals on apixaban (TA275), dabigatran (TA249), rivaroxaban (TA256) and dronedarone (TA197). A technology appraisal of edoxaban (TA355) has been published more recently and is currently not incorporated into the guideline.

Equalities

Topic experts highlighted the following potential equality issues:

  • Inequality of treatment for frail and older people in residential care who may not be receiving anticoagulation.

  • Specific ethnic minority groups most at risk or affected by AF and with related comorbidities may not be receiving equality of diagnosis and treatment. Differing risk profiles may have implications for the management of risk.

Overall decision

After considering all the evidence and views of topic experts, we decided that a partial update with modified scope is necessary for this guideline.

See how we made the decision for further information.


This page was last updated: 12 September 2017