Effect of digoxin on circadian blood pressure values in patients with congestive heart failure

BackgroundThe aim of the study was to investigate the effect of chronic digoxin treatment on circadian blood pressure profile in normotensive patients with mild congestive heart failure.MethodsIn a randomized double‐blind, placebo‐controlled cross‐over protocol, 12 normotensive patients with mild congestive heart failure took digoxin or placebo for a total of 7 days. Automatic 24‐h ambulatory blood pressure measurements were carried out at day 7, of either digoxin or placebo.ResultsDiastolic blood pressure significantly decreased and systolic blood pressure significantly increased during overnight sleep in the digoxin phase compared to placebo. Digoxin had no effect on either systolic or diastolic blood pressure during daytime. Heart rate decreased in the overnight sleeping phase but did not differ significantly between placebo and digoxin phase.ConclusionsDigoxin significantly decreases diastolic blood pressure during overnight sleep in patients with congestive heart failure. This effect is likely to be caused by reduction of sympathetic activity or increase of parasympathetic activity. Increase of systolic blood pressure during sleep is probably caused by the positive inotropic effect of the drug.