In Hospital Treatment of New Onset Atrial Fibrillation

Warning

All patients with new onset atrial fibrillation should be considered for rate / rhythm control, and the risk of embolic complications should be assessed and treated as appropriate. Rate and rhythm control is considered below. Decision making with regard to thrombo-embolic protection is covered in the ‘Anticoagulation in New onset AF flow chart’.

1. Treat underlying precipitating cause

E.g. infection, myocardial ischaemia, metabolic derangement, LVF etc. This may be all that is required. If resting rate is >100 bpm, or there is evidence of myocardial ischaemia or LVF precipitated by the rapid heart rate, rate control is indicated.

2. Rate Control

  • First line therapy should be β –blockade Bisoprolol 2.5mg od or Metoprolol 25mg bd - up titrate as necessary. (Metoprolol has a shorter half life and should be used in patients where there is concern about tolerability of β –blockers.)
  • Where β –blockers are contra-indicated, rate limiting Ca2+ channel blockers such as Diltiazem or Verapamil can be used (caution in heart failure)
  • Digoxin- Use for inactive, elderly or evidence of LVF or hypotension.
    Dose: - 500μg at baseline and a further 500μg dose 6 hours later, followed by 250μg daily. (Reduced with abnormal renal function.) Use oral Digoxin unless unable to swallow.

3. Emergency Cardioversion

Only in patients who are acutely unwell due to high ventricular rates and hypotension. e.g. patients in cardiogenic shock. Always weigh, the risks of anaesthetic and embolic complication.

4. Rhythm control

Early cardioversion
Restoration of sinus rhythm is sometimes necessary or desirable e.g. in patients with paroxysmal AF and in the post operative period.
If the patient is not adequately anti-coagulated, cardioversion should not be undertaken if the duration of AF is >48hrs. Patient can be considered for out-patient cardioversion following at least 3 weeks of anti-coagulation.
If patients are at medium or high risk of embolic complications, anti-coagulation in the longer term should be considered and instituted following cardioversion. If there is doubt about the duration of AF, or early cardioversion is important clinically, TOE guided cardioversion can be considered.


Chemical cardioversion
This can be done with either Amiodarone or Flecainide. Flecainide should not be used in patients with ischaemic heart disease or a structurally abnormal heart. D/W cardiologist.

Editorial Information

Last reviewed: 30/09/2021

Next review date: 30/09/2023

Author(s): Donaldson, Gillian.

Version: CARD004/03

Author email(s): gillian.donaldson@borders.scot.nhs.uk.

Reviewer name(s): Dr Anne Scott.

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