Self-administered Antidysrhythmics for Perceived Episodes of Atrial Fibrillation

Abstract & Commentary

Source: Alboni P, et al. Outpatient treatment of recent-onset atrial fibrillation with the "pill-in-the-pocket" approach. N Engl J Med 2004;351:2384-2391.

Depending on the clinical presentation, there is currently a wide range of treatment options for the ED management of patients with atrial fibrillation (AF). This Italian study evaluated the feasibility, efficacy, and safety of an outpatient pill-in-the-pocket approach, whereby patients who were treated successfully in the ED with flecainide or propafenone were provided the same medication for self-administration and outpatient use for recurrent AF episodes.

Investigators studied 268 patients presenting to the ED who were diagnosed with AF of recent duration (fewer than 48 hours of onset) and treated with either oral flecainide (300 mg or 200 mg if fewer than 70 kg) or propafenone (600 mg or 450 mg if fewer than 70 kg). Of those patients, 210 patients had restoration of sinus rhythm either in the ED or as an inpatient and were enrolled in the study. The patients were discharged with the same medication (74 with flecainide; 136 with propafenone) that was used in the study and told to self-administer the drug as an outpatient in the event of recurrent heart palpitations.

During the follow-up period (mean duration of 15 months), 165 patients had a total of 618 episodes of palpitations. In 569 of those episodes, patients administered the medication as directed (mean time to self-administration was 36 minutes); patients noted successful resolution of their symptoms within 6 hours (mean time 113 minutes) in 534 episodes (94%). In the remaining 35 episodes, treatment was unsuccessful or resolution occurred after 6 hours; and 26 of those resulted in a return visit to the ED. An additional five ED visits occurred in the 49 episodes where self-treatment was not attempted by the patient. Adverse effects occurred in 12 patients (7%) and included one episode of rapid ventricular response and 11 cases of noncardiac side effects.

The investigators retrospectively compared palpitation episodes, ED visits, and hospitalizations before and after the study in the 210 patients enrolled. For the group, mean episodes per month were the same (59.8 vs. 54.5 before and after the study respectively), but ED visits per month markedly decreased (45.6 vs. 4.9 respectively) as did hospitalizations per month (15.0 vs. 1.6 respectively). Twenty-seven patients did drop out of the study because either the drug was ineffective or the patient was switched to prophylactic treatment due to frequent recurrences.

Based on their findings, the authors conclude that the pill-in-the-pocket approach of self-administration of either flecainide or propafenone for episodes of atrial fibrillation is feasible, safe, and effective for a select group of patients who present to the ED with dysrhythmia. In addition, this approach appears to reduce repeat ED visits and hospitalizations.

Commentary by Ted Chan, MD, FACEP

The management of patients who present to the ED with new-onset atrial fibrillation continues to evolve. Flecainide and propafenone are rapidly-acting class IC antidysrhythmics that have efficacy in converting AF of recent onset to sinus rhythm.1 The study investigators found that patients who are treated in the ED with these medications can treat themselves safely and effectively for recurrent AF episodes on an outpatient basis.

Many points are worth emphasizing with this study. First, both flecainide and propafenone were used in this study and no data are provided actually comparing the two drugs to determine if one was better. Second, patients self-administered the medication with the onset of palpitations, but there are no data confirming the presence of AF. Thus, patients took the medications based on nonspecific symptoms that may or may not have been the dysrhythmia.

Third, and most importantly, exclusion criteria for this study were numerous and included the presence of common cardiac conditions (e.g., ischemic heart disease, cardiomyopathy, heart failure history, left ventricular dysfunction, preexcitation, bundle-branch block, second and third degree atrioventricular block) and noncardiac conditions (e.g., liver or renal dysfunction). As a result, at one site, only 12% of patients presenting to the ED with AF actually were eligible for the study. Accordingly, application of this pill-in-the-pocket approach must be limited to a very select AF patient population presenting to the ED.

Dr. Chan, Associate Clinical Professor of Medicine, Emergency Medicine, University of California, San Diego, is on the Editorial Board of Emergency Medicine Alert.

Reference

1. Capucci A, et al. Conversion of recent-onset atrial fibrillation by a single oral loading dose of propafenone or flecainide. Am J Cardiol 1994;74:503-505.