Comparative clinical evaluation of two salts of quinidine using 24-hour Holter monitor recordings.

In 13 patients admitted to a coronary care unit, antiarrhythmic efficacy and safety of quinidine gluconate in a nonmatrix formulation were compared to placebo and quinidine sulfate. Both quinidine preparations were effective in reducing the number and severity of ventricular and supraventricular extrasystoles when compared to placebo. Except for a few cases in which quinidine gluconate was significantly more effective, both quinidine preparations appear to have similar clinical antiarrhythmic efficacy and duration of action. A 24-hour Holter ECG monitoring device and electrocardioscanner were utilized in this research. No major unexpected adverse effects were observed.