Management of atrial fibrillation in primary care

Atrial fibrillation (AF) is one of the most common sustained cardiac arrhythmias in adults. It is defined as a supraventricular tachycardia with uncoordinated atrial electrical activation leading to ineffective atrial contraction.¹It is currently estimated that 2-4% of the adult population have AF. This number is expected to increase due to both an ageing population and also ongoing investigation of patients for undiagnosed AF.²

AF investigation and management is a common clinical scenario in primary care and one that is only going to increase in the future. Given the potential consequences of AF, including a 5-fold increase in stroke risk, the correct investigation and management of these patients is vital.³

Investigation of atrial fibrillation

Patients with the following symptoms should be investigated for AF: breathlessness, chest discomfort, palpitations, syncope, dizziness, transient ischaemic attack (TIA) and stroke.

Atrial fibrillation should be investigated using a 12-lead ECG and patients with suspected paroxysmal AF not shown on 12-lead ECG should have ambulatory ECG monitoring or an event recorder. The length of time this is required to be in place will depend upon the frequency of the patients’ symptoms.³

Some smart devices are now actively set up to monitor for episodes of irregular heart rhythm and so maybe able to detect AF in a non-clinical setting.⁴Yet further investigation is still required as there are some questions regarding efficacy.⁵

Management options

The Atrial Fibrillation Better Care pathway should be followed when commencing treatment for patients with AF.⁶ This pathway features an ‘ABC’ approach and is associated with improved patient outcomes.

‘A’ – anticoagulation

Stroke risk should be assessed using the CHA₂DS₂-VASc scoring tool with anticoagulation offered to all patients scoring >2 and to men who score >1.⁷

Bleeding risk needs to be taken into account and the ORBIT bleeding risk score⁸ is now recommended by NICE due to improved accuracy in absolute bleeding risk compared to other bleeding risk tools.²

This new tool takes into account multiple different factors including: age, Hb, renal function, previous history of bleeding and concomitant use of anti-platelets. The tool then provides a risk stratification of low, medium and high risk for the patient which can then be used in conjunction with the CHA₂DS₂-VASc score to appropriately council patients to both the risks and benefits of anticoagulation.⁸

NICE advises that direct oral anticoagulants (DOAC) be prescribed in preference to Vitamin K antagonists and that these are only used if DOACs are contraindicated or not tolerated. Patients on any form of anticoagulation should be reviewed at least annually to review adequate use of anticoagulation.

Age

Sex

Congestive heart failure history

Hypertension history

Previous stroke/TIA/thromboembolism

Vascular disease history

(Previous MI, peripheral arterial disease or aortic plaque)

Diabetes history

Table 1. CHA2DS2-VASc Stroke Risk Score⁷

Sex

Hemoglobin

Male:

Female:

Age >74

Bleeding history

(Prev. GI bleed, intracranial bleed or haemorrhagic stroke)

GFR

Treatment with antiplatelet agents

Table 2. ORBIT Bleeding Risk Score⁸

‘B’ – better symptom control

Rate control is an integral part of AF treatment; however, this should be led by symptoms and lenient rate control of 1 Beta-blockers (excluding sotalol) or rate limiting calcium channel blockers (eg. diltiazem) should be used as first-line treatment for rate control.

Digoxin can be considered first-line in patients with non-paroxysmal AF who perform little or no exercise or where first-line medications are contraindicated due to comorbidities or patient preference.²

If monotherapy does not succeed in providing symptomatic control then combination therapy with any two of bisoprolol, diltiazem and digoxin can be used. In patients where rhythm control is thought to be appropriate, referral to secondary care should be made (as outlined below).

‘C’ – cardiovascular risk factors and concomitant disease: detection and management

Patients should be reviewed to identify concomitant diseases and unhealthy lifestyle factors as management of these complements stroke prevention as well as decreasing symptom severity. Weight loss for obese patients, increasing exercise and decreasing alcohol intake are all factors that can improve a patient’s cardiovascular risk as well as the disease burden of atrial fibrillation.¹

When to refer to secondary care?

Patients who are thought to be appropriate for rhythm control (cardioversion or ablation) should be referred to a cardiologist for further review.⁹

This includes patients that have a potentially reversible cause (eg. infection), patients with heart failure that is thought to be primarily caused by or worsened by the AF, or if the AF is of new onset.

The following patients should also be referred to secondary care:

When rate control fails to control symptoms
If there is evidence of valvular heart disease or left ventricular systolic dysfunction on echocardiography
If they have prolonged QT or there is evidence of Wolf-Parkinson-White syndrome on their ECG.⁹

When to refer patients with AF to Cardiology

For consideration of Rhythm control

Rate control has failed to control symptoms

Echo evidence of LVSD or Valvular heart disease

Prolonged QTc

Concomitant Wolf-Parkinson-White Syndrome

Conclusion

Patients with atrial fibrillation are increasingly being investigated and managed in primary care. Patients should be thoroughly investigated for AF if it is thought to be a possible diagnosis due to the significant complications of the condition. Even those that present evidence from smart devices should still have clinical investigation.

Anticoagulation risks and benefits should be discussed with the patient and these discussions can be aided by the use of clinical risk stratification tools such as CHA₂DS₂-VASc and ORBIT. Once a diagnosis of AF has been made patients should have their cardiovascular risk factors explored and addressed.

Dr Edward Brown MBChB, MRCP, IMT3, Queen Elizabeth Hospital, Gateshead, Tyne and Wear

Conflict of interest: none declared

To find out more about management of atrial fibrillation please attend our annual conference – Health and ageing in a post-Covid NHS – on 18th October 2022 at Hallam Conference Centre, London.

Professor Ahmet Fuat will be talking about new developments.

References

Hindricks G, Potpara T, Dagres N, et al. 2020 ESC Guidelines for the diagnosis and management of atrial fibrillation developed in collaboration with the European Association of Cardio-Thoracic Surgery (EACTS). European Heart Journal. 2020 Aug 29;42(5)
Atrial fibrillation: diagnosis and management. Guidance. NICE [Internet]. nice.org.uk. Available from: https://www.nice.org.uk/guidance/ng196/chapter/Recommendations#detection-and-diagnosis
Safe and effective management of stroke prevention in atrial fibrillation [Internet]. NICE. Available from: https://www.nice.org.uk/sharedlearning/safe-and-effective-management-of-stroke-prevention-in-atrial-fibrillation#:~:text=Atrial%20fibrillation%20(AF)%20is%20the
Heart rate notifications on your Apple Watch [Internet]. Apple Support. 2019. Available from: https://support.apple.com/en-us/HT208931
Perez MV, Mahaffey KW, Hedlin H, et al. Large-Scale Assessment of a Smartwatch to Identify Atrial Fibrillation. New England Journal of Medicine 2019; 14;381(20): 1909–17
Lip G. The ABC pathway: an integrated approach to improve AF management. Nature Reviews Cardiology 2017; volume 14: 627-628
O’Brien EC, Simon DN, Thomas LE, et al. The ORBIT bleeding score: a simple bedside score to assess bleeding risk in atrial fibrillation, European Heart Journal 2015; 36(46): 3258–3264, https://doi.org/10.1093/eurheartj/ehv476
CHA₂DS₂-VASc Score for Atrial Fibrillation Stroke Risk – MDCalc [Internet]. Mdcalc.com. MDCalc; 2019. Available from: https://www.mdcalc.com/cha2ds2-vasc-score-atrial-fibrillation-stroke-risk
Atrial Fibrillation [Internet]. NICE. Available from: https://cks.nice.org.uk/topics/atrial-fibrillation/