Flecainide is well-tolerated and effective in patient with atrial fibrillation at 12 months: a retrospective study

Introduction: Current atrial fibrillation (AF) guidelines recommend flecainide as a first-line rhythm control option in patients without structural heart disease. While there is proven efficacy in clinical trials and guideline support, it is hypothesized that flecainide may be underutilized due to negative outcomes in the CAST trial and that adverse effects are less common than previously perceived. Methods: This retrospective chart review evaluated patients ⩾18 years initiated on flecainide for AF from August 2011 to October 2016 by a cardiology provider at the study site. Exclusion criteria included: <5 days of flecainide therapy, AF due to a reversible cause, and inadequate documentation. The primary outcome was efficacy of flecainide at maintaining symptomatic control at 6 and 12 months. Secondary outcomes included characterization of alterations in rhythm control strategies and documented normal sinus rhythm per electrocardiogram at 6 and 12 months. Results: Of the 326 patients identified, 144 patients were included. After 6 and 12 months, 102 patients (70.8%) and 89 patients (61.8%) of the 144 were symptomatically controlled. Atenolol use ( p = 0.024), female sex ( p = 0.006), hypertension ( p = 0.040), and dronedarone failure ( p = 0.012) were associated with flecainide discontinuation at 6 months. At 12 months, only previous propafenone failure ( p = 0.032) was significant. Of the 144 patients, 16 (11.1%) reported adverse effects with dizziness, hot flashes, bradycardia, and headache (1.4% each) being the most common. Conclusion: Flecainide is a well-tolerated medication, even at 12 months, with very minor adverse effects. These results support the utility of flecainide in guideline recommended patient populations.