Antiarrhythmic Effects of Combining Dofetilide and Ranolazine in a Model of Acutely Induced Atrial Fibrillation in Horses

Helena Carstensen, Line Kjær, Maria Mathilde Haugaard, Mette Flethøj, Eva Zander Hesselkilde, Jørgen K Kanters, Steen Pehrson, Rikke Buhl, Thomas Jespersen

11 Citations (Scopus)
64 Downloads (Pure)

Abstract

Background: Antiarrhythmic compounds against atrial fibrillation (AF) often have reduced efficacy and may display cardiac and/or noncardiac toxicity. Efficacy can be improved by combining 2 compounds with distinct mechanisms, and it may be possible to use lower doses of each compound, thereby reducing the likelihood of adverse side effects. The purpose of this study was to investigate whether the effective doses of dofetilide and ranolazine can be reduced if the drugs are combined. Methods: Dofetilide, ranolazine, and a combination of these were administered in 4 incremental dosing regimens to horses with acutely pacing-induced AF. Time to cardioversion, atrial effective refractory period, and AF vulnerability and duration were assessed. Results: Of 8 horses, 6 cardioverted to sinus rhythm after infusion with a combination of 0.889 mg/kg dofetilide and 0.104 mg/kg ranolazine. Two horses cardioverted with 0.104 mg/kg ranolazine alone, and 3 cardioverted with 0.889 mg/kg dofetilide alone. The combination therapy decreased AF vulnerability (P < 0.05) and AF duration (P < 0.05). No change in atrial effective refractory period was detected with any of the drugs. Conclusions: The combination of dofetilide and ranolazine showed increased antiarrhythmic effects on acutely induced AF in horses, affecting time to cardioversion, AF vulnerability, and AF duration.

Original languageEnglish
JournalJournal of Cardiovascular Pharmacology
Volume71
Issue number1
Pages (from-to)26-35
Number of pages10
ISSN0160-2446
DOIs
Publication statusPublished - 1 Jan 2018

Fingerprint

Dive into the research topics of 'Antiarrhythmic Effects of Combining Dofetilide and Ranolazine in a Model of Acutely Induced Atrial Fibrillation in Horses'. Together they form a unique fingerprint.

Cite this