Discussion
In this study, IV sotalol was found to be a safe and well tolerated method of sotalol initiation for both atrial and ventricular arrhythmias. Almost 1 in 4 patients undergoing IV sotalol initiation had serious bradycardia, but 6/7 of them were on AV nodal blocking agents at the time of initiation. Discontinuing or dose reducing these agents prior to IV sotalol initiation may help to mitigate these effects. QT prolongation was noted only in the context of serious bradycardia in our IV sotalol cohort, with a rate of approximately 10% matching those found in other real-world data.8 No patients undergoing oral sotalol initiation had the drug discontinued due to bradycardia or QT prolongation, but 35% of the patients had doses reduced to less efficacious doses.9No patients in either group had life threatening sustained ventricular arrhythmias during their hospitalization. Most notably, patients undergoing IV sotalol initiation had a significantly shorter hospital length of stay than patients undergoing oral sotalol initiation, with a mean difference of 2.6 days. Based on cost estimates done by Varela et al, this represents potential savings of more than $4000 per patient.3
Additional analysis was performed evaluating changes in the QT/QTc interval during IV sotalol infusion and after the first and second oral dose. The increase in the QT/QTc interval by the end of the intravenous infusion approximates that seen at discharge. These findings provide preliminary clinical corroboration for pharmacokinetics-pharmacodynamic models that simulate peak serum concentration of sotalol immediately after infusion.7Taken together, this suggests that discharge after infusion may be safe from a QT prolongation perspective. Efforts to decrease IV sotalol initiation time are already underway, with the DASH-AF study looking at discharge after IV infusion and a single oral sotalol dose currently enrolling patients.10