Acute in vitro effects of dronedarone, an iodine-free derivative, and amiodarone, on the rabbit sinoatrial node automaticity: a comparative study.
Amiodarone is a potent antiarrhythmic drug commonly used in the treatment of supraventricular and ventricular arrhythmias. Dronedarone is a recently developed iodine-free compound (Sanofi Recherche), structurally related to amiodarone. Amiodarone and dronedarone have shown similar long-term effects on sinoatrial node automaticity in vivo and in vitro in the rabbit heart. In the present study, we used a microelectrode technique to compare the acute in vitro electrophysiologic effects of amiodarone (100 microM) and dronedarone (100 microM) on the rabbit sinus node. Like amiodarone, dronedarone induces a marked reduction in sinus node automaticity, evidenced by decreases in spontaneous beating rate, action potential amplitude, and slope of phase 4 depolarization. Isoproterenol dose-dependently increases sinus node automaticity in the presence of either amiodarone or dronedarone. The data suggest that dronedarone may be a useful antiarrhythmic alternative to amiodarone in the treatment of supraventricular arrhythmias.
Celestino
Daniela
D
Laboratorio de Electrofisiología Celular División Cardiología, Hospital Ramos Mejía, Buenos Aires, Argentina.
Medei
Emiliano
E
Moro
Sandra
S
Elizari
Marcelo V
MV
Sicouri
Serge
S
D000200:Action Potentials / Q000187:drug effects*; D000638:Amiodarone / Q000031:analogs & derivatives* / Q000494:pharmacology; D000818:Animals; D000889:Anti-Arrhythmia Agents / Q000494:pharmacology*; D000077764:Dronedarone; D004594:Electrophysiology; D066298:In Vitro Techniques; D007545:Isoproterenol; D008297:Male; D008839:Microelectrodes; D011817:Rabbits; D012849:Sinoatrial Node / Q000187:drug effects*; D013617:Tachycardia, Supraventricular / Q000188:drug therapy
D000889:Anti-Arrhythmia Agents; D000077764:Dronedarone; D007545:Isoproterenol; D000638:Amiodarone