To compare the individual and combined electrophysiological effects of amiodarone and procainamide, 35 patients with sustained ventricular arrhythmias underwent programmed stimulation in the control state, after procainamide (mean concentration, 8.7 +/- 2.8 micrograms/ml), after 13 +/- 2 days of amiodarone (1,400 mg/day x 7 days, then 400 mg/day), and after amiodarone with procainamide (mean pr...

BACKGROUND There is increasing evidence that both functional reentrant wave fronts and multiple wavelets are present during ventricular fibrillation (VF). However, the effects of procainamide on the characteristics of activation waves during VF are poorly understood. METHODS AND RESULTS Seven dogs were studied; six underwent subendocardial chemical ablation procedures. A plaque with 317 to 48...

In a prospective, double-blind, randomized, placebocontrolled study we investigated the facilitating influence of intravenous procainamide on conversion of atrial flutter by rapid atrial pacing. Fifty consecutive patients with spontaneous sustained atrial flutter were 1:1 randomized into two homogenous groups: group A received 10 mg.kg-1 procainamide intravenously, group B placebo. After infusi...

Drug-induced lupus is a side effect of deliberate ingestion of various medications, but its etiology, underlying mechanisms, and pathogenesis are puzzling. In vivo metabolic transformation of lupus-inducing drugs to reactive products explains how a heterogeneous set of drugs can mediate the same disease syndrome. Evidence has accumulated that drugs are transformed by extracellular oxidation fro...

In this issue of the Journal, Chang et al1 present a thought-provoking, single-center retrospective analysis of 37 patients receiving either procainamide or IV amiodarone for refractory supraventricular arrhythmias (SVA), excluding junctional ectopic tachycardia (JET). They compare the relative efficacy of the drugs, finding procainamide to be fully successful in 50% of cases, whereas amiodaron...

In this study, the duration of the QRS complex during ventricular pacing was used as an index of intraventricular conduction to quantitate the rate-dependent effects of intravenous lidocaine, procainamide and amiodarone. Right ventricular apical pacing (15 to 20 beats) was performed at cycle lengths of 600, 500, 400, 350, 300, 275 and 250 ms, before and 5 minutes after the intravenous administr...

BACKGROUND The selective class III antiarrhythmic agent ibutilide prolongs action potential duration and terminates atrial flutter (AFL) and fibrillation (AF), but the mechanism of its antiarrhythmic efficacy in humans has not been fully characterized. This study compared the antiarrhythmic effects of ibutilide with the class IA agent procainamide in humans during AFL and AF. Antiarrhythmic dru...

Overt systemic inflammatory response is a predisposing mechanism for infection-induced skeletal muscle damage and rhabdomyolysis. Aberrant DNA methylation plays a crucial role in the pathophysiology of excessive inflammatory response. The antiarrhythmic drug procainamide is a non-nucleoside inhibitor of DNA methyltransferase 1 (DNMT1) used to alleviate DNA hypermethylation. Therefore, we evalua...

Persistence of preexcitation in sinus rhythm with procainamide infusion has been reported to occur in patients with a short anterograde accessory pathway effective refractory period (AERPAP) and this test has been proposed as a reliable noninvasive method to identify patients with the Wolff-Parkinson-White syndrome who are at risk of sudden death. However, sudden death correlates best with a sh...