New-onset atrial fibrillation

Suspect new-onset AF if the patient has an irregularly irregular pulse with or without any one of: palpitations (the cardinal symptom); dyspnoea; chest pain; fatigue; dizziness; polyuria; syncope.

Perform manual pulse palpation and conduct an immediate 12-lead ECG.

Regardless of the duration of onset of the patient’s arrhythmia, do not delay emergency synchronised direct current (DC) cardioversion in the following groups as their condition may be life-threatening: features of haemodynamic instability; symptoms of acute myocardial ischaemia; suspected or confirmed serious precipitating illness requiring hospital care; AF alongside a pre-excitation syndrome such as Wolff-Parkinson-White syndrome; signs or symptoms of acute stroke.

Urgently admit any patient who is haemodynamically compromised to an acute medical unit. Call for anaesthetic support to sedate the patient before DC cardioversion. In patients not already on therapeutic anticoagulation, immediately start anticoagulation pre-cardioversion. Seek senior and/or specialist review; this should not delay urgent DC cardioversion.

Follow the integrated Atrial fibrillation Better Care (ABC) pathway for holistic management of any patient with AF: A - Anticoagulation/Avoid stroke; B - Better symptom management; C - Cardiovascular and comorbidity optimisation (including lifestyle changes).

In all patients, prioritise calculating stroke risk using the CHA₂DS₂-VASc score.

If you are considering anticoagulation, use ORBIT or HAS-BLED scores to assess the risk of a major bleed, identify (and subsequently manage) modifiable risk factors for bleeding, and flag the ‘high bleeding risk’ patients for early review and follow-up.

Start rate control in any patient without life-threatening haemodynamic instability while initially assessing the patient. If the patient still has symptoms after their rate has been controlled or rate control has not been achieved, consider rhythm control.

Identify unhealthy lifestyle factors and give the patient advice on these to help prevent recurrence. Work with the patient to identify strategies for comprehensive risk-factor modification and interventions targeting underlying conditions that may apply.

Atrial fibrillation (AF) is a supraventricular tachyarrhythmia with uncoordinated atrial electrical activation and consequently ineffective atrial contraction.[1]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). Eur Heart J. 2021 Feb 1;42(5):373-498. https://academic.oup.com/eurheartj/article/42/5/373/5899003 http://www.ncbi.nlm.nih.gov/pubmed/32860505?tool=bestpractice.com Electrocardiographic characteristics include:[1]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). Eur Heart J. 2021 Feb 1;42(5):373-498. https://academic.oup.com/eurheartj/article/42/5/373/5899003 http://www.ncbi.nlm.nih.gov/pubmed/32860505?tool=bestpractice.com

• Irregularly irregular R-R intervals (where atrioventricular conduction is not impaired)

• Absence of distinct repeating P waves

• Irregular atrial activations.

New-onset AF is defined as a new onset or a first detectable episode of AF, whether symptomatic or not. This topic covers symptomatic new-onset AF in the non-valvular and non-surgical settings. Paroxysmal and asymptomatic new-onset AF are covered in Chronic atrial fibrillation.