Intravenous sildenafil significantly reduced vulnerability to induced atrial fibrillation in sheep by decreasing both AF incidence and duration.
Does 10 mg intravenous sildenafil reduce vulnerability to induced atrial fibrillation in anaesthetised sheep?
Acute intravenous sildenafil reduces vulnerability to induced atrial fibrillation in a sheep model by favorably altering atrial electrophysiology.
Sildenafil has been shown to decrease ventricular arrhythmias. We investigated whether sildenafil could similarly decrease atrial fibrillation (AF) burden through direct effects on atrial electrophysiology. In vivo electrophysiological studies were performed in 12 anaesthetised sheep before and after 10 mg intravenous sildenafil. Sildenafil decreased AF vulnerability by decreasing both AF incidence and duration. The antiarrhythmic actions of sildenafil were associated with increases in atrial effective refractory period and atrial wavelength, together with a decrease in alternans magnitude which were expected to limit both AF duration and incidence respectively. The antiarrhythmic effects of acute sildenafil should be confirmed in man. • Intravenous sildenafil significantly reduced vulnerability to AF in sheep. • Sildenafil increased atrial effective refractory period and atrial wavelength. • Sildenafil also decreased alternans magnitude. • These effects are well-established as anti-arrhythmic. • The observed reduction of AF by sildenafil warrants further investigation in man.
Madders et al. (2026) studied Atrial fibrillation (n=12). Sildenafil vs. Baseline (before sildenafil) was evaluated on AF vulnerability (incidence and duration). Intravenous sildenafil significantly reduced vulnerability to induced atrial fibrillation in sheep by decreasing both AF incidence and duration.