Efficacy of azimilide and dofetilide in the dog right atrial enlargement model of atrial flutter.

Introduction: Azimilide dihydrochloride blocks both the rapid (I(Kr)) and slow (I(Ks)) components of the delayed rectified K+ current; dofetilide blocks only I(Kr). Their efficacies were assessed on atrial flutter reentrant circuits in dogs with surgically induced right atrial enlargement.

Methods And Results: Multiple biopsies of the tricuspid valve and banding of the pulmonary artery in male mongrel dogs made them susceptible, about 3 weeks postoperatively, to stimulation-induced sustained (5 min or longer) atrial flutter.

Effects of azimilide dihydrochloride on circus movement atrial flutter in the canine sterile pericarditis model.

Introduction: The effects of a Class III agent, azimilide dihydrochloride, on atrial flutter circuits were studies in a functional model of single loop reentrant atrial flutter using dogs, 3 to 5 days after production of sterile pericarditis.

Methods And Results: A computerized mapping system was used to construct activation maps from 138 to 222 epicardial sites in the right atrium. Doses of 3, 10, and 30 mg/kg i.