Rapid intravenous infusion of d-1 sotalol: time to onset of effects on ventricular refractoriness, and safety.

Abstract

d-1 sotalol is one of the most effective antiarrhythmic agents currently available for ventricular tachyarrhythmias, but the recommended infusion rate of 10-20 min is too slow for rapid pharmacological termination of sustained ventricular tachycardia (VT) or for use during cardiac arrest. The safety of the drug and time lag from its rapid administration to onset of significant effects on ventricular refractoriness is unknown. One hundred and nine patients with a history of spontaneous and inducible sustained ventricular tachyarrhythmias were studied. d-1 sotalol (1.5 mg.kg-1) was infused over 5 min in the first 57 patients (mean age 61 +/- 13 years, mean ejection fraction 37 +/- 15%, range 15-70%). d-1 sotalol was then given over 1 min in the next 52 patients (mean age 61 +/- 12 years, mean ejection fraction 35 +/- 11%, range 18-58%). The time course of change in right ventricular effective refractory period (RVERP) was measured in 15 consecutive patients following the 5 min infusion and in all 52 patients following the bolus injection. Following the 5 min infusion, RVERP increased rapidly from a baseline of 231 +/- 17 ms, reaching a plateau of 268 +/- 23 ms at 10 min. Following the 1 min injection, RVERP increased virtually immediately from a baseline of 237 +/- 25 ms to reach a plateau of 271 +/- 31 ms at 5 min. Two patients (one in each group) developed symptomatic hypotension; both responded to volume replacement.(ABSTRACT TRUNCATED AT 250 WORDS)