Clinical and Safety Outcomes
Changes in HR and QT/QTc interval over the course of IV sotalol
initiation are described in Table 2. At the end of the 60-minute IV
sotalol infusion, the mean QT/QTc interval had increased from baseline
by 29.7 ms; at discharge after two additional oral doses, the QT/QTc
interval had increased from baseline by 29.8 ms (Figure 1).
Of the 29 patients undergoing IV sotalol initiation, 7 had
discontinuation of the infusion due to significant bradycardia (Table
3). 6 out of 7 of these patients were on AV nodal blocking agents (5 on
metoprolol and 1 on diltiazem) that were not discontinued or dose
reduced prior to the start of IV sotalol. Of the 7 patients who
developed significant bradycardia, 3 also had prolongation of the QT
interval that would have required discontinuation. A total of 22/29
patients (75.9%) underwent successful IV sotalol initiation. All
patients undergoing PO sotalol initiation were able to complete their
sotalol load, but 7 required dose reductions due to bradycardia and/or
QT prolongation. The two patients who required dose reduction due to
bradycardia did not have their AV nodal blocking agents held prior to
oral sotalol load. Four patients required cardioversion to sinus rhythm
at the end of oral load. Average length of stay for the IV sotalol
initiation group was 1 day compared to 3.6 days in the PO sotalol group
(p < 0.001).