A Korean population-based study suggests an association between antiarrhythmic drugs (AADs) and risk of pacemaker implantation or syncope in patients of new-onset atrial fibrillation (AF). A total of 770,977 new-onset AF cases were identified from 2013 to 2019 and 142,141 patients were prescribed AADs within 1 year of AF diagnosis. After multivariate adjustment, use of AADs (including flecainide, propafenone, pilsicainide, amiodarone, dronedarone, and sotalol) was associated with 3.5-, 2.0-, and 5.0-fold increased risk of pacemaker implantation or syncope, syncope, and pacemaker implantation, respectively. Propensity score–matched analysis revealed similar results, demonstrating a significant association between AAD use and the risk of pacemaker implantation or syncope. This association was consistent across various subgroups. Women were more susceptible to adverse effects of AADs than men. The findings suggest cautious when using AADs, especially in older patients and women, although early rhythm control with AAD is an established treatment strategy for patients with new-onset AF and may significantly reduce the risk of the cardiovascular disease death, stroke, or hospitalization for worsening heart failure or acute coronary syndrome. Negative dromotropic effects of AADs via ion channel blocking may cause bradyarrhythmias. Source: https://www.jacc.org/
