MP-453091-9 COMPARISON OF TRADITIONAL THREE-DAY ORAL SOTALOL LOADING TO A SINGLE-DAY INTRAVENOUS SOTALOL INITIATION PROTOCOL: AN OBSERVATIONAL STUDY

Abstract

Sotalol is an antiarrhythmic medication used to prevent atrial fibrillation (AF). In March 2020, intravenous (IV) sotalol received FDA approval to be used as a loading dose for initiation in patients with AF. The IV administration shortens the time to achieve steady-state to just one day, in comparison to a traditional three-day oral sotalol load. There is limited data comparing IV sotalol to oral sotalol loading regarding efficacy and safety. This study aims to compare the efficacy and safety of initiating a three-day oral sotalol load to a single-day IV sotalol dosing protocol in patients with AF. This is a retrospective study that included patients initiated with either IV or oral sotalol between January 2018 and August 2022 at a single academic medical center. The primary endpoint was maintenance of sinus rhythm (SR) at discharge and 30 days post initiation. The secondary endpoints included incidence of QTc prolongation >500ms, heart rate <40bpm, ventricular arrhythmias, and discontinuation of sotalol after initiation. A total of 95 patients (64.2% male) underwent a single-day IV sotalol loading protocol and 96 patients (67.7% male) received a three-day oral sotalol initiation. When comparing to the oral group at baseline, patients in the IV group were more likely to have persistent AF (77.9% vs 51%, p<0.001), advanced age (71.6 + 7.4 yrs vs 68.4 + 8.6 yrs, p=0.008), and alcohol use (45.3% vs 18.8%, p<0.001). They were also less likely to be in SR on admission (1.1% vs 16.7%, p<0.001) compared to the oral group. SR was maintained at discharge in 81.1% and 83.3% (p=0.4) and at 30-days in 59% and 66.7% (p=0.141) in the IV and oral groups, respectively. A QTc >500ms was observed at discharge in 6.6% and 9.9% (p=0.591) and at 30-days in 10.3% and 12.5% (p=0.798) in the IV and oral group, respectively. Discontinuation of sotalol during initiation occurred in 4 patients (4.2%) in the IV group and 7 patients (7.29%) in the oral group, due to adverse events such as bradycardia, QTc prolongation, and failure to maintain SR (p=0.537). No patients experienced ventricular arrhythmias. Despite more risk factors for treatment failure, AF patients initiated on sotalol therapy with IV loading achieved similar maintenance of SR at discharge and at 30 days compared to oral loading with no difference in adverse events.