What to do if a patient on flecainide (Flecainide) for premature ventricular contractions (PVCs) develops atrial flutter?

Management of Flecainide-Induced Atrial Flutter

When a patient on flecainide for PVCs develops atrial flutter, perform catheter ablation of the cavotricuspid isthmus (CTI) and continue the flecainide therapy. 1

Immediate Management

Acute Rate Control

• Add AV nodal blocking agents immediately to prevent dangerous 1:1 AV conduction, which can cause ventricular rates exceeding 200 bpm and potentially trigger ventricular fibrillation 2, 3
• Initiate beta blockers, diltiazem, or verapamil for rate control 1
• The FDA explicitly warns that flecainide slows atrial flutter rate, enabling 1:1 AV conduction with paradoxical increase in ventricular rate 2

Critical Safety Consideration

Do not attempt synchronized cardioversion without first controlling the ventricular rate, as case reports document ventricular fibrillation occurring during cardioversion of flecainide-induced 1:1 atrial flutter 3

Definitive Management Strategy

Catheter Ablation (Class IIa Recommendation)

The ACC/AHA/HRS guidelines specifically address this scenario: catheter ablation of the CTI is reasonable in patients who develop atrial flutter as a result of flecainide used for other arrhythmias 1

The rationale for this approach:

• Ablation success rates exceed 90% for CTI-dependent flutter 1
• Ablating the flutter circuit allows continued flecainide use for the original indication (PVCs in this case) 1
• This strategy decreases atrial flutter incidence while facilitating ongoing pharmacological management 1

Why Continue Flecainide After Ablation?

• The patient was presumably responding well to flecainide for PVC suppression before flutter developed 1
• Flecainide-induced flutter represents a predictable proarrhythmic effect (occurring in 0.4-10.5% of patients), not treatment failure for the primary indication 2, 4
• CTI ablation eliminates the substrate for typical flutter while preserving the therapeutic benefit for PVCs 1

Alternative Approach If Ablation Not Feasible

If the patient refuses ablation or has contraindications:

Discontinue Flecainide

• Switch to alternative PVC suppression therapy such as beta blockers or calcium channel blockers as first-line 1
• Consider amiodarone if PVC burden is high and causing symptoms, though this carries different toxicity concerns 1

Do Not Continue Flecainide Without Ablation

The guidelines explicitly caution against continuing flecainide/propafenone in patients with atrial flutter due to risk of 1:1 conduction, even with concomitant AV nodal blocking agents 1, 2

Common Pitfalls to Avoid

Never use flecainide as monotherapy in patients with any atrial arrhythmia - always co-administer AV nodal blocking agents 1, 2

Do not assume the flutter will resolve spontaneously while continuing flecainide - this is a drug-induced proarrhythmic effect that persists with ongoing exposure 2, 4

Avoid the temptation to simply add rate control and continue flecainide long-term without addressing the flutter substrate - this leaves the patient at ongoing risk of breakthrough 1:1 conduction 1, 2

Anticoagulation Considerations

Treat this patient's stroke risk identically to atrial fibrillation using CHA₂DS₂-VASc scoring, regardless of whether the primary arrhythmia is flutter or PVCs 1