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).