From the Guidelines
Flecainide is recommended as a first-line treatment for patients with atrial fibrillation, particularly those with no or minimal structural heart disease, at a daily dosage of 200-300 mg, due to its efficacy in maintaining sinus rhythm and relatively low risk of adverse effects 1.
Key Considerations
- Flecainide works by blocking sodium channels in heart cells, which affects the heart's electrical system and helps prevent abnormal electrical signals that cause arrhythmias.
- The typical adult dosage ranges from 200-300 mg daily, with treatment usually starting at a lower dose and gradually increasing as needed under medical supervision.
- Flecainide requires careful monitoring, especially when treatment begins, as it can occasionally worsen arrhythmias in some patients or cause new rhythm problems.
- It should not be used in patients with structural heart disease or heart failure due to increased risk of serious side effects.
- Common side effects include dizziness, visual disturbances, headache, nausea, and fatigue.
- Regular ECG monitoring is essential during flecainide therapy to ensure safety and effectiveness.
Important Interactions
- Flecainide interacts with several other drugs, so patients should inform their healthcare provider about all medications they're taking.
- Combination therapy with beta-blocking agents may be used to enhance efficacy and reduce the risk of one-to-one conduction over the AV node if atrial flutter occurs.
Patient Selection
- Flecainide is particularly effective in patients with lone AF, and it may be used in cases of vagally mediated AF.
- Patients with adrenergically mediated AF may require alternative treatments, such as beta-blockers or sotalol.
Monitoring and Follow-up
- Prospective trial data on upper limits of drug-induced increases in QRS duration or QT prolongation are not available, but the writing committee recommends that QRS widening should not exceed 150% of the pretreatment QRS duration, and the corrected QT interval in sinus rhythm should remain below 520 ms 1.
- Plasma potassium and magnesium levels and renal function should be checked periodically to prevent proarrhythmia.
From the FDA Drug Label
In patients without structural heart disease, flecainide acetate tablets, USP are indicated for the prevention of: •paroxysmal supraventricular tachycardias (PSVT), including atrioventricular nodal reentrant tachycardia, atrioventricular reentrant tachycardia and other supraventricular tachycardias of unspecified mechanism associated with disabling symptoms •paroxysmal atrial fibrillation/flutter (PAF) associated with disabling symptoms Flecainide acetate tablets, USP are also indicated for the prevention of: •Documented ventricular arrhythmias, such as sustained ventricular tachycardia (sustained VT), that in the judgment of the physician are life-threatening
The main indications for flecainide are:
- Paroxysmal supraventricular tachycardias (PSVT)
- Paroxysmal atrial fibrillation/flutter (PAF)
- Documented ventricular arrhythmias, such as sustained ventricular tachycardia (sustained VT) 2
From the Research
Flecainide Overview
- Flecainide is a class Ic antiarrhythmic agent that has been available in Europe since 1982 3.
- It is used to treat atrial and ventricular arrhythmias, including atrial fibrillation (AF) and supraventricular tachycardias 4.
Clinical Use
- Flecainide is recommended as a first-line therapy for pharmacological conversion and maintenance of sinus rhythm in patients with AF and no documented structural heart disease 3, 4.
- It is also used to prevent ventricular tachyarrhythmias in patients with catecholaminergic polymorphic ventricular tachycardia associated with ryanodine receptor and calsequestrin mutations 4.
- Flecainide is not recommended in patients with structural heart disease due to high proarrhythmic risk, as shown in the Cardiac Arrhythmia Suppression Trial (CAST) study 3, 4, 5, 6.
Safety and Efficacy
- Flecainide has shown good efficacy and safety for both cardioversion and sinus rhythm maintenance in carefully selected patients with AF and no structural heart disease 3.
- Recent studies have demonstrated a good effectiveness and safety profile of flecainide in different patient populations, including those with supraventricular arrhythmias 5.
- However, the increased mortality associated with flecainide in the CAST study still casts a shadow over its clinical profile, and its use should be carefully considered in patients with structural heart disease 6.
Practical Aspects
- Flecainide is available in various formulations, including controlled release, intravenous, and immediate release, which can improve patient compliance 6.
- The drug's electrophysiological properties, effects on the conduction system, and major side effects and contraindications should be carefully considered in clinical practice 6.