Treatment of Atrial Flutter
The definitive treatment for atrial flutter is catheter ablation of the cavotricuspid isthmus (CTI), which is highly effective and should be offered to patients with symptomatic or recurrent atrial flutter. 1
Initial Management Based on Hemodynamic Status
Hemodynamically Unstable Patients
- Immediate synchronized cardioversion is recommended for patients with atrial flutter who are hemodynamically unstable 1, 2
- Cardioversion for atrial flutter can be successful at lower energy levels than for atrial fibrillation 1, 2
- Anticoagulation considerations should be addressed when possible, but should not delay cardioversion in truly unstable patients 2, 3
Hemodynamically Stable Patients
Rate Control Strategy
- Intravenous or oral beta blockers, diltiazem, or verapamil are first-line agents for acute rate control in hemodynamically stable patients 1, 2
- Intravenous diltiazem is the preferred calcium channel blocker due to its safety and efficacy profile 1, 4
- Esmolol is generally the preferred intravenous beta blocker for acute rate control because of its rapid onset 4
- For patients with systolic heart failure where beta blockers are contraindicated or ineffective, intravenous amiodarone can be useful for acute rate control 1, 4
- Important precautions:
- Avoid diltiazem and verapamil in patients with advanced heart failure, heart block, or sinus node dysfunction without pacemaker therapy 1, 4
- Avoid calcium channel blockers and beta blockers in patients with pre-excited atrial flutter (Wolff-Parkinson-White syndrome) as they can facilitate antegrade conduction along the accessory pathway, potentially leading to ventricular fibrillation 4, 3
Rhythm Control Strategy
Acute Conversion to Sinus Rhythm
- Elective synchronized cardioversion is indicated in stable patients when pursuing a rhythm-control strategy 1, 2
- Pharmacological cardioversion options include:
- Oral dofetilide or intravenous ibutilide, which can convert atrial flutter to sinus rhythm in approximately 60% of cases 2, 4
- Rapid atrial pacing is useful for acute conversion in patients with pacing wires already in place (e.g., permanent pacemaker, ICD, or temporary wires after cardiac surgery) 1, 2
Long-term Rhythm Maintenance
- For maintenance of sinus rhythm in patients with symptomatic recurrent atrial flutter, the following drugs can be used depending on underlying heart disease:
- Amiodarone, dofetilide, and sotalol are options for most patients 4, 3
- Flecainide or propafenone may be considered only in patients without structural heart disease 4, 5
- Caution: Flecainide and propafenone can cause 1:1 atrioventricular conduction during atrial flutter, resulting in dangerously rapid ventricular rates 5, 6
Anticoagulation Considerations
- Acute antithrombotic therapy in patients with atrial flutter should follow the same protocols as for atrial fibrillation 1, 2
- The risk of stroke in atrial flutter is similar to that in atrial fibrillation, with thromboembolism rates averaging 3% annually 1, 3
- Anticoagulation should be continued according to stroke risk factors, not based on the success of rhythm control 2, 7
Definitive Treatment
- Catheter ablation of the CTI is the preferred definitive treatment for symptomatic atrial flutter or flutter refractory to pharmacological rate control 1, 4
- Success rates for CTI ablation exceed 90% for typical atrial flutter 8, 9
- Ablation prevents development of tachycardia-mediated cardiomyopathy associated with poorly controlled atrial flutter 1, 4
Important Clinical Considerations
- Rate control can be more difficult to achieve in atrial flutter than in atrial fibrillation due to less concealed AV nodal conduction 1, 4
- Atrial flutter and atrial fibrillation frequently coexist—22-50% of patients develop atrial fibrillation within 14-30 months after CTI ablation for atrial flutter 4, 3
- Risk factors for developing atrial fibrillation after atrial flutter ablation include prior atrial fibrillation, depressed left ventricular function, structural heart disease, and increased left atrial size 4
- Propafenone and flecainide should not be used to control ventricular rate during atrial flutter due to risk of 1:1 conduction 5, 6