LONG-TERM ADHERENCE TO FLECAINIDE AS A RHYTHM CONTROL THERAPY IN RECURRENT ATRIAL FIBRILLATION - A RETROSPECTIVE COHORT STUDY

• Background: The choice of rhythm control drugs for recurrent atrial fibrillation (AF) remains empirical and is based on the safety profile rather than predicted efficacy. Flecainide is recommended for prevention of AF recurrence in patients without structural heart disease however predictors of treatment success are insufficiently studied. Objective: To assess clinical characteristics associated with flecainide treatment success in patients with recurrent AF. Methods: Using hospital medical records, 135 consecutive adult AF patients who were referred for in-hospital initiation of flecainide were included (median age 62 (IQR 53-70) years, 35% females, 28% persistent AF, median CHA2DS2-VASc score 1, median follow up time 14.5 (IQR 3.3-32.7) months). Patient characteristics at admission, including left atrial enlargement (LAE) assessed as LA volume index >34 ml/m2, were retrieved from medical records. Kaplan Meier curve and Cox regression analysis were used to analyse the association between the clinical characteristics and the likelihood of the drug discontinuation due to failed rhythm control efficacy (primary endpoint) or discontinuation for any reason (secondary endpoint). Results: By the end of follow up 88 patients (65.0%) had continued flecainide therapy. Reasons for discontinuation were failed efficacy (16.0%), side effects (7.0%) or safety issues (16.0 %) such as proarrhythmia (6.7%), heart failure (2.2%), coronary heart disease (1.5%), QRS widening (1.5%), QTc ≥500 ms (0.7%) or AV block II (0.7%). Age ≥60 years, male gender, height and LAE were significant predictors of therapy discontinuation in the univariate analysis, however only LAE (HR=3.9 95% CI 1.1-13.5 for the primary (Figure A) and HR=2.5 95%CI 1.3-4.9 for the secondary endpoints) and age ≥60 years (HR=3.9 95% CI 1.1-11.9 for the primary and HR=2.2 95%CI 1.1-4.3 for the secondary endpoint) remained independent predictors of therapy discontinuation in the multivariate analysis. The outcome did not differ between paroxysmal and persistent AF (Figure B). [Formula presented] [Formula presented] Conclusion: LAE and age ≥60 years were associated with flecainide rhythm control failure in patients with recurrent AF. The vast majority of all treatment failures occured within 6 months from the treatment start. AF type did not significantly predict treatment efficacy.

Subject headings

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Kardiologi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Cardiac and Cardiovascular Systems (hsv//eng)

Keyword

flecainide

adult

atrial fibrillation

atrioventricular block

CHA2DS2-VASc score

clinical feature

cohort analysis

conference abstract

controlled study

drug efficacy

drug safety

drug therapy

drug withdrawal

female

follow up

gender

heart failure

heart left atrium

heart proarrhythmia

human

ischemic heart disease

Kaplan Meier method

major clinical study

male

medical record

middle aged

outcome assessment

persistent atrial fibrillation

QTc interval

retrospective study

side effect

treatment failure

univariate analysis

Publication and Content Type

kon (subject category)

ref (subject category)