Referenced in: none

Automatically associated channels: Kir2.3 , Kv1.4 , Kv10.1 , Kv3.1 , Kv4.3

Title: d,l-Sotalol reverses abbreviated atrial refractoriness and prevents promotion of atrial fibrillation in a canine model with left ventricular dysfunction induced by atrial tachypacing.

Authors: Tamotsu Sakamoto, Akira Fujiki, Yosuke Nakatani, Masao Sakabe, Koichi Mizumaki, Norio Hashimoto, Hiroshi Inoue

Journal, date & volume: Circ. J., 2009 Oct , 73, 1820-8

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/19713653

Abstract
This study evaluated antiarrhythmic effects of d,l-sotalol in a canine atrial fibrillation (AF) model with left ventricular dysfunction.Thirteen beagles (Sotalol group n=7 and Control group n=6) were subjected to atrial tachypacing (ATP) (400 beats/min) with intact atrioventricular conduction for 4 weeks. Oral d,l-sotalol (2 mg/kg) was administered 1 week after starting ATP and continued throughout the experiment. One week after starting ATP, atrial effective refractory periods (AERPs) were shortened in both groups. However, d,l-sotalol treatment gradually prolonged AERP, resulting in a significant prolongation of AERP compared with the Control group at 4 weeks (Control 76 +/-4 and Sotalol 126 +/-5 ms, p<0.01). d,l-Sotalol treatment showed lower AF inducibility and shorter AF duration at 4 weeks. In the control group, expressions of L-type Ca(2+) channel alpha1c and Kv4.3 mRNA were downregulated by 46.2% and 43.0%, respectively, after 4 weeks of ATP; d,l-sotalol treatment did not affect these changes.d,l-Sotalol treatment prolonged AERP, even after atrial electrical remodeling had developed, and prevented AF perpetuation without affecting downregulated expression of L-type Ca(2+) channel alpha1c and Kv4.3 mRNA in an ATP-induced canine AF model.