Atrial flutter - Emergency medicine revision
Overview
Atrial flutter (AFL) is an organised macro‑reentrant atrial tachyarrhythmia, most commonly cavotricuspid isthmus-dependent (typical flutter). It carries a stroke risk comparable to atrial fibrillation and many acute management principles follow the same pathways (NICE NG196).
In the ED the priorities are rapid recognition, assessment of haemodynamic stability, deciding rate versus rhythm control, and appropriate anticoagulation planning.
Pathophysiology and clinical significance
- Rapid organised atrial depolarisation (classically ≈300/min) with variable conduction to the ventricles.
- Atrial contraction is ineffective; thrombus formation and embolic stroke risk are similar to AF - apply the same stroke‑risk assessment and anticoagulation principles (CHA2DS2‑VASc) (NICE NG196).
- Typical flutter is often amenable to curative catheter ablation; ED care focuses on stabilisation, symptom control and anticoagulation decisions.
Typical presentations
- Symptoms: palpitations, dyspnoea, presyncope/syncope, chest pain, or decompensated heart failure.
- Rhythm can be regular (fixed AV block, e.g. 2:1) or irregular (variable block), the latter sometimes mimicking AF.
ECG recognition - key features
- Organised atrial “flutter” (F) waves at a rate often near 300/min.
- Saw‑tooth F waves most obvious in inferior leads II, III and aVF (usually inverted there).