(Circulation. 1995;92:1517-1525.)
© 1995 American Heart Association, Inc.
Articles |
From the University Hospital, Department of Cardiology, Freiburg,
Germany.
1 See "Appendix" for affiliations of
authors.
Background There is increasing interest in pure class III antiarrhythmic compounds, ie, drugs in which the electrophysiological effect is confined to the propensity for producing an isolated lengthening of action potential duration. d-Sotalol represents the prototype of such pure class III agents. This double-blind, placebo-controlled, randomized dose-finding study evaluated the antiarrhythmic efficacy and safety of d-sotalol in patients with symptomatic chronic ventricular ectopy.
Methods and Results A total of 233 patients presenting with
30 premature ventricular contractions (PVCs) per hour
during drug-free Holter monitoring randomly received placebo or
d-sotalol at dosages of 50, 100, or 200 mg BID. Drug
efficacy was assessed by repeat Holter monitoring at the end of
double-blind therapy. There was a dose-dependent increase in QT
and QTc duration, indicating class III activity. A
dose-related decrease in hourly PVC counts was observed, reaching
statistical significance for patients receiving 200 mg
d-sotalol BID (311 PVCs/h during baseline compared with 135
PVCs/h during active treatment, P<.05). Analysis of
the primary efficacy criterion (ie,
75% reduction in total PVCs/h)
revealed a significant treatment effect only for the highest
d-sotalol dose, with 8 patients (14%) meeting this
criterion. Eighteen patients reported side effects, which led to drug
discontinuation in 5. One sudden death and one nonfatal cardiac arrest
occurred in patients with dilative cardiomyopathy
receiving 200 mg d-sotalol BID. No incidence of
torsade de pointes was reported.
Conclusions d-Sotalol exerts dose-dependent class III activity in patients with symptomatic ventricular ectopy. Its PVC-suppressing activity is modest and becomes evident predominantly at dosages of 200 mg administered BID. The observation of drug-associated serious adverse arrhythmic events emphasizes the need for individualized careful dose titration, particularly in patients with advanced organic heart disease.
Key Words: tachyarrhythmias antiarrhythmia agents d-sotalol ventricles repolarization
This article has been cited by other articles:
![]() |
S. Sicouri, S. Moro, and M. V. Elizari d-Sotalol Induces Marked Action Potential Prolongation and Early Afterdepolarizations in M but Not Epicardial or Endocardial Cells of the Canine Ventricle Journal of Cardiovascular Pharmacology and Therapeutics, January 1, 1997; 2(1): 27 - 37. [Abstract] [PDF] |
||||
|
Circulation Home | Subscriptions | Archives | Feedback | Authors | Help | AHA Journals Home | Search Copyright © 1995 American Heart Association, Inc. All rights reserved. Unauthorized use prohibited. |