Atrial Fibrillation 🫀
Clinical guide for managing atrial fibrillation (AF, a fib). Rate vs rhythm control, anticoagulation, CHA₂DS₂-VASc and HAS-BLED calculators for stroke and bleeding risk assessment.
📞 What to Ask on the Phone
- Is the patient symptomatic (palpitations, chest pain, breathlessness, dizziness)?
- Are there signs of haemodynamic instability? If so, escalate to senior immediately.
- Duration of the arrhythmia (new onset vs known AF)?
- Any previous episodes or cardioversions?
- Is the patient anticoagulated? What is their current medication list?
🔍 Immediate Considerations
- Assess vitals: BP, HR, O2 sats, RR, temperature
- Identify red flags: chest pain, syncope, hypotension, pulmonary oedema
- Review ECG and compare to any prior
- Consider reversible causes: sepsis, PE, thyrotoxicosis, alcohol, electrolyte imbalance
- On any rate/rhythm control medication already? Anticoagulated?
🧪 Initial Assessment
- ECG – confirm AF, rate, and rule out other arrhythmias
- Bloods: FBC, U&E, LFT, TFTs, CRP, Troponin if chest pain
- CXR if concern for pulmonary oedema or infection
- VBG if concerned re: lactic acidosis or electrolyte disturbance
- ECHO if new-onset or considering cardioversion (may be outpatient)
🩹 Management
- If haemodynamically unstable → heparinise & urgent DC cardioversion (call senior/cardiology/anaesthetics)
- If stable, consult registrar and consider:
- → Anticoagulation - Rivaroxaban 20mg PO OD, discuss with senior if CrCl <50. Consider aspirin if <48h onset and low stroke risk with cardioversion.
- → Rate control with beta-blocker (e.g. bisoprolol 5mg PO stat). Give MgSO4 2g IV.
- → Give IV metoprolol 2.5mg if no response to oral beta-blocker after 30 mins (repeat at 20 minutes if no response).
- → Asthmatics: substitute with Verapamil 2mg IV & Diltiazem 120mg PO
- Do not cardiovert unless duration & anticoagulation status are clear
- If duration <48h and patient is low risk, consider rhythm control (discuss with senior)
✅ Actions for Interns
- Document vitals, symptoms, and management clearly.
- Ensure senior is aware of any new or unstable AF
- Order or chase relevant investigations
- Clarify and communicate anticoagulation plan
- Arrange follow-up with cardiology or further workup if needed
CHA₂DS₂-VASc Score
Stroke risk assessment for atrial fibrillation
Risk Factors
Assessment Result
0
✅Low risk
HAS-BLED & ORBIT Scores
Bleeding risk assessment tools
HAS-BLED Score
💉Risk Factors
HAS-BLED Result
0
Acceptable bleeding risk
ORBIT Score
⚖️Risk Factors
ORBIT Result
0
Low bleeding risk
Related NICE guidance
NICENICE NG196 — Atrial fibrillation: diagnosis and management
Full guidance on nice.org.uk. BetterCall is not endorsed by NICE.
Educational reference only. Medical disclaimer