Abstract 14189: Risk Prediction for Adverse Events During Initiation of Sotalol and Dofetilide for the Treatment of Atrial Fibrillation
Introduction: Inpatient antiarrhythmic drug initiation for atrial fibrillation is mandated for dofetilide (DF) and recommended for sotalol (SL) particularly if proarrhythmia risk factors are present. We assessed the hypothesis that low-risk patients can be identified to safely allow outpatient loading.
Methods: A single-center retrospective cohort study was performed on patients loaded with DF or SL. Risk factors for adverse events (AEs), defined as any arrhythmia or EKG change requiring dose reduction or cessation, were identified.
Results: Of 329 patients, 227 (69%) received SL and 102 (31%) DF. Mean age 63±13 years, 70% male, and baseline QTc = 440±37 ms; A total of 105 AEs occurred in 92 patients: QTc prolongation or ventricular tachyarrhythmia in 70 patients (67% of AEs), bradyarrhythmias in 35 patients (33% of AEs) with some experiencing both AE types (Table ). Ventricular arrhythmias were seen in 23 patients (7%) and torsades de pointes in 1 (0.3%). Total AE rates were similar between drugs (p=0.09), however DF patients had more QTc prolongation or ventricular arrhythmias (p=0.001). In SL patients, there were no predictors for QTc prolongation or ventricular proarrhythmia. In DF patients, higher baseline QTc interval (OR=1.64 /25msec, p=0.01) was an independent predictor of QTc prolongation or ventricular proarrhythmias. For patients without proarrhythmia risk factors, overall AE rate was 26%.
Conclusions: AEs are common during DF and SL loading but rarely severe in inpatients. QTc predicts AEs for DF patients only and AE are common even in “low risk” patients. These results support in-hospital drug loading for all DF and SL patients.
- © 2013 by American Heart Association, Inc.