Pharmacokinetics and pharmacodynamic effects of digoxin in dilated cardiomyopathies. Influence of nicardipine

• Published in: Archives des maladies du coeur et des vaisseaux Vol. 80; no. 12; p. 1773
• Main Authors: Scanu, P, Commeau, P, Huret, B, Gérard, J L, Debruyne, D, Moore, N, Lamy, E, Dorey, H, Grollier, G, Potier, J C
• Format: Journal Article
• Language: French
• Published: France 01-11-1987
• Subjects: Aged; Cardiomyopathy, Dilated - drug therapy; Cardiomyopathy, Dilated - metabolism; Digoxin - blood; Digoxin - pharmacokinetics; Digoxin - pharmacology; Drug Therapy, Combination; Echocardiography; Hemodynamics - drug effects; Humans; Male; Middle Aged; Nicardipine - pharmacology
• ISSN: 0003-9683

Numerous studies have been devoted to the effect of slow calcium channel inhibitors on plasma digoxin concentrations. The principal drugs tested, verapamil and nifedipine, were found to increase significantly plasma digoxin levels mainly by reducing digoxin total clearance. Very few studies on the nicardipine-digoxin interaction have been reported. The dual purpose of the present study was to evaluate the influence of orally administered nicardipine on plasma digoxin concentrations over 24 hours and to measure possible variations in the pharmacodynamic effects of digoxin in 9 patients with chronic congestive heart failure. The pharmacodynamic assessment involved simple and cross-sectional echocardiography, systolic time interval measurements and cardiac catheterization. In these patients under chronic digoxin treatment, oral nicardipine had little effect on plasma digoxin concentrations which increased but not significantly; no sign of digitalis toxicity was observed. Nicardipine improved left ventricular function and myocardial contractility by reducing after-load, the nicardipine-induced peripheral vasodilatation tending to counteract the digoxin-induced vasoconstriction.