Treatment of Atrial Flutter
Immediate Management Based on Hemodynamic Status
If the patient is hemodynamically unstable (hypotension, ongoing myocardial ischemia, or heart failure), perform immediate synchronized cardioversion without delay. 1, 2
- Atrial flutter cardioversion requires lower energy levels than atrial fibrillation, making it highly effective even at initial attempts. 1, 3
- Address anticoagulation considerations when possible, but do not delay cardioversion in truly unstable patients. 1
Rate Control for Hemodynamically Stable Patients
For stable patients, initiate rate control with intravenous beta-blockers or diltiazem as first-line therapy. 1, 2
Preferred Agents and Dosing:
- Esmolol is the preferred IV beta-blocker due to rapid onset and short half-life allowing titration: 500 mcg/kg IV bolus over 1 minute, then 50-300 mcg/kg/min infusion. 2, 3
- Diltiazem is the preferred calcium channel blocker: 0.25 mg/kg IV bolus over 2 minutes, then 5-15 mg/hour infusion. 2, 3
- Oral beta-blockers, diltiazem, or verapamil can be used for ongoing rate control. 1
Critical Contraindications to Avoid:
- Never use diltiazem or verapamil in patients with pre-excited atrial flutter (Wolff-Parkinson-White syndrome), as this can precipitate ventricular fibrillation by blocking the AV node and forcing conduction down the accessory pathway. 1, 4
- Avoid calcium channel blockers and beta-blockers in patients with advanced heart failure, heart block, or sinus node dysfunction without pacemaker. 1, 3
- For patients with systolic heart failure where beta-blockers are contraindicated or ineffective, use intravenous amiodarone for rate control. 1, 2
Important Clinical Caveat:
- Rate control is significantly more difficult to achieve in atrial flutter than atrial fibrillation due to less concealed AV nodal conduction, so expect to use higher doses or combination therapy. 1, 3
Rhythm Control Strategy
Electrical Cardioversion:
- Elective synchronized cardioversion is indicated in stable patients pursuing rhythm control after appropriate anticoagulation. 1, 3
- For atrial flutter >48 hours or unknown duration, provide therapeutic anticoagulation for 3 weeks before and 4 weeks after cardioversion. 2, 3
Pharmacological Cardioversion:
- Intravenous ibutilide is effective in approximately 60% of cases for acute pharmacological cardioversion. 1, 3, 5
- Oral dofetilide is an alternative pharmacological option. 1, 3
- Critical warning: Ibutilide causes QT prolongation and risk of torsades de pointes, especially in patients with reduced left ventricular ejection fraction—continuous monitoring is mandatory. 1
Rapid Atrial Pacing:
- Particularly useful in post-cardiac surgery patients with temporary atrial wires already in place, with success rate >50%. 1, 2
Anticoagulation Requirements
Treat atrial flutter with the same anticoagulation protocols as atrial fibrillation—the stroke risk is equivalent at approximately 3% annually. 1, 2, 3
- Initiate acute antithrombotic therapy in all patients with atrial flutter. 1
- Use CHA₂DS₂-VASc score to guide long-term anticoagulation decisions, just as with atrial fibrillation. 2
Long-Term Definitive Treatment
Catheter ablation of the cavotricuspid isthmus (CTI) is the most effective long-term treatment for typical atrial flutter with >90% success rate. 1, 2, 5, 6
Indications for Catheter Ablation:
- Symptomatic atrial flutter refractory to pharmacological rate control. 1
- Recurrent symptomatic atrial flutter. 1
- Patient preference to avoid long-term antiarrhythmic therapy. 5, 6
Antiarrhythmic Drug Maintenance (if ablation not pursued):
- For patients without structural heart disease: Dronedarone, flecainide, propafenone, or sotalol. 7
- For patients with structural heart disease but LVEF >35%: Dronedarone, sotalol, or amiodarone. 7
- For patients with LVEF <35%: Amiodarone is the only recommended drug. 7
Critical Warning for Class IC Agents:
- When using flecainide or propafenone, always coadminister AV nodal blocking drugs (beta-blockers or calcium channel blockers) to prevent 1:1 AV conduction, which can cause dangerously rapid ventricular rates. 1, 8, 9
- Flecainide and propafenone are contraindicated in patients with structural heart disease or prior myocardial infarction due to increased mortality risk. 9
Common Pitfalls to Avoid
- Failing to recognize hemodynamic instability requiring immediate cardioversion. 1
- Using verapamil or diltiazem in pre-excitation syndromes. 1
- Underestimating stroke risk—atrial flutter carries the same thromboembolic risk as atrial fibrillation. 1, 3
- Insufficient monitoring for QT prolongation when using ibutilide. 1
- Using class IC agents without concomitant AV nodal blockade. 1