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