Atrial flutter
Atrial flutter is a macro-reentrant atrial tachyarrhythmia, typically a right atrial cavotricuspid isthmus circuit, producing sawtooth flutter waves at about 300 per minute with a regular ventricular response (often 2:1, giving a rate near 150). It carries the same stroke risk as atrial fibrillation, and cavotricuspid isthmus ablation is highly effective and curative for typical flutter.
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What this article covers
- Overview
Definition: atrial flutter is a macro-reentrant atrial tachyarrhythmia, most commonly a counterclockwise circuit around the right atrial cavotricuspid isthmus (typical flutter).
- Epidemiology
Frequently coexists with atrial fibrillation and shares its risk factors.
- Risk factors
Structural and atrial disease: heart failure, valvular disease, and prior cardiac surgery or ablation.
- Pathophysiology
Macro-reentrant circuit: a large reentry loop, typically around the tricuspid annulus through the cavotricuspid isthmus, drives the atria at about 300 per minute.
- Clinical features
Palpitations and a regular fast pulse, often around 150 per minute.
- Differential diagnosis
Atrial fibrillation: irregularly irregular without organized flutter waves (atrial fibrillation).
- Diagnosis
Establish with an ECG showing sawtooth flutter waves and a regular ventricular response: the diagnostic basis is a 12-lead ECG demonstrating regular atrial flutter (F) waves near 300 per minute…
- Management
First-line, treat instability: synchronized cardioversion for hemodynamic compromise; atrial flutter often converts with low energy.
- Complications
Cardioembolic stroke and systemic embolism.
- Prognosis
Excellent for typical flutter after ablation, which is curative in most.
- Prevention
Anticoagulate per CHA2DS2-VASc to prevent stroke.
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Related articles
- Atrial fibrillation
Atrial fibrillation is a supraventricular tachyarrhythmia with disorganized atrial activation and an irregularly irregular ventricular response, the most common sustained arrhythmia and a major cause of stroke. Diagnosis is by ECG showing no discrete P waves with irregular RR intervals, and management addresses rate or rhythm control, stroke prevention by CHA2DS2-VASc-guided anticoagulation, and the underlying cause.
- Supraventricular tachycardia
Supraventricular tachycardia is any tachyarrhythmia arising at or above the AV node, usually a regular narrow-complex tachycardia. Acute management of a stable regular narrow-complex SVT is vagal maneuvers then adenosine; unstable patients receive synchronized cardioversion, and definitive therapy is catheter ablation.