Safety of outpatient commencement of sotalol

Background Inpatient monitoring is recommended for sotalol initiation. Objective Assess the safety of outpatient sotalol commencement. Methods This is a multi-centre, retrospective, observational study of patients initiated on sotalol in outpatient setting. Serial ECG monitoring at day-3, day-7, 1-month and subsequently as indicated was performed. QTc interval and clinical events were evaluated. Results Between 2008-2023, 880 consecutive patients who were commenced on sotalol were evaluated. Indications were atrial fibrillation/flutter 87.3% (n=768), ventricular arrhythmias 9.9% (n=87), and other 2.8% (n=25). Daily dose at initiation was 131.0±53.2mg/day. QTc interval increased from baseline (431±32ms) to 444±37ms (Day3) and 440±33ms (Day7) after sotalol initiation (p<0.001). Within the first week, QTc prolongation led to the discontinuation of sotalol in 4 and dose reduction in 1. No ventricular arrhythmia, syncope, or death were observed during the first week. Dose reduction due to asymptomatic bradycardia occurred in 3 and discontinuation due to dyspnoea in 3 within the first week. Overall, 1.1% developed QTc prolongation (>500ms/>25% from baseline);4 within 3-days, 1 within 1-week, 4 within 60-days, and 1 after >3 years. Discontinuation of sotalol due to other side effects occurred in 41 patients within the first month of therapy. Conclusion Sotalol initiation in outpatient setting with a protocolized follow-up is safe, with no recorded sotalol-related mortality, ventricular arrhythmias, or syncope. There was a low incidence of significant QTc prolongation necessitating discontinuation within the first month of treatment. Importantly, we observed a small incidence of late QT prolongation; highlighting the need for vigilant outpatient surveillance of individuals on sotalol.