When propafenone is given with digoxin, digoxin serum concentrations increase. Although the digoxin-propafenone interaction is well known clinically, the mechanism by which propafenone interferes with digoxin elimination is unclear. To test the hypothesis that propafenone or one or both of its two major metabolites, 5-hydroxypropafenone (5-OHP) and N-depropylpropafenone (NDPP), inhibit the P-gl...

The effects of conventional amphotericin B (AmB) dissolved in sodium deoxycholate on microsomal cytochrome P-450 concentrations and propafenone metabolism to 5-hydroxy-propafenone and N-desalkyl-propafenone were compared with those of liposomal AMB (Li-AMB) in rats. AmB (3 mg/kg/day, intravenously [i.v.]) given for 4 days caused a significant decrease in the concentration of hepatic microsomal ...

Propafenone is an antiarrhythmic drug that produces a variable degree of beta-blockade in humans and is administered as a racemate. To examine the relative contribution of the individual enantiomers to pharmacologic effects seen during treatment with propafenone, we assessed the steady-state plasma concentrations of (+)-S-propafenone and (-)-R-propafenone in seven patients who were on long-term...

AIM To assess the efficacy of propafenone in prevention of atrioventricular nodal reentrant tachycardia (AVNRT) and orthodromic atrioventricular tachycardia (AVRT) based on the clinical results of arrhythmia recurrence and find the electrophysiological predictor of propafenone effectiveness. METHODS This retrospective study included 44 participants in a 12-month period, who were divided in tw...

Objective—To assess the eVect of adding propafenone to atrial overdrive for the prevention of atrial arrhythmia episodes in patients with DDD pacemakers. Design—22 patients (8 female, 14 male, mean (SD) age 67 (9) years, range 48 to 77) with DDD pacemakers and frequent paroxysmal atrial arrhythmia episodes were evaluated in a randomised crossover study. Setting—University hospital. Methods—Atri...

BACKGROUND Therapy with racemic compounds produces effects that can be attributed to both (S)- and (R)-enantiomers. Here we have tested the hypothesis that an enantiomer-enantiomer interaction would modulate the effects of treatment with a racemate, the antiarrhythmic propafenone. Previous studies have shown that while the enantiomers of propafenone exert similar sodium channel-blocking (QRS wi...

The responsiveness of ventricular tachycardia (VT) to propafenone, a new antiarrhythmic agent, was evaluated in the conscious dog during acute myocardial infarction (AMI). AMI was produced in the anesthetized closed-chest dogs with an intracoronary catheter system by permanent occlusion in eight dogs and by 2-hour occlusion followed by reperfusion ofthe left anterior descending coronary artery ...

STUDY OBJECTIVE To compare placebo vs two different regimens of propafenone administration--intravenous administration or short-term oral loading--in converting recent-onset atrial fibrillation to sinus rhythm. DESIGN Single-blind placebo-controlled study. PATIENTS Eighty-seven patients with atrial fibrillation of recent onset (< or = 7 days' duration) admitted to the hospital without signs...

BACKGROUND AND PURPOSE Human ether-a-go-go related gene (HERG) channel inhibitors may be subdivided into compounds that are trapped in the closed channel conformation and others that dissociate at rest. The structural peculiarities promoting resting state dissociation from HERG channels are currently unknown. A small molecule-like propafenone is efficiently trapped in the closed HERG channel co...

The objective of this randomized, double-blind, placebo-controlled clinical trial was to test the efficacy and safety of a new sustained-release preparation of the antiarrhythmic drug propafenone (propafenone SR) in reducing the frequency of symptomatic arrhythmia recurrences in patients with atrial fibrillation (AF). Patients with a history of symptomatic AF who were in sinus rhythm were rando...