Digoxin withdrawal after cardiac failure in patients with sinus rhythm.

A double-blind placebo-controlled crossover trial of digoxin withdrawal was undertaken in 22 patients with sinus rhythm who had a previous history of frank heart failure and were taking therapeutic doses of the drug. During the course of the study, 14 patients showed no clinical change whether taking digoxin or placebo, five patients deteriorated on placebo (four with heart failure and one with supraventricular tachycardia), and three on digoxin (two with heart failure and one with digoxin toxicity). These differences were not statistically significant. Compared to placebo, patients, while taking digoxin, had lower resting heart rates and significant shortening of all the systolic time intervals. The drug appears to exert a sustained positive inotropic effect during maintenance therapy, but this is not of clinical benefit to the majority of patients.