Proarrhythmic proclivity of left-stellate ganglion stimulation in a canine model of drug-induced long-QT syndrome type 1.

Background: Left-stellate ganglion stimulation (LSGS) can modify regional dispersion of ventricular refractoriness, promote triggered activity, and reduce the threshold for ventricular fibrillation (VF). Sympathetic hyperactivity precipitates torsades de pointes (TdP) and VF in susceptible patients with long-QT syndrome type 1 (LQT1). We investigated the electromechanical effects of LSGS in a canine model of drug-induced LQT1, gaining novel arrhythmogenic insights.

Pharmacological prevention and termination of focal atrial fibrillation.

Aims: Patients undergo ablation for focal atrial fibrillation (AF) as a result of failure of anti-arrhythmic drugs. Our basic studies have implicated cholinergic and adrenergic neurotransmitter release as the underlying mechanism for focal AF. Therefore, we tested the efficacy of a combination of sodium channel-blocking agents with additional vagolytic properties and a β-blocker to terminate and prevent focal AF.