Pulmonary Artery Denervation Inhibits Left Stellate Ganglion Stimulation-Induced Ventricular Arrhythmias Originating...

Area of Science:

• Cardiovascular Physiology
• Autonomic Nervous System Research
• Cardiac Electrophysiology

Background:

• Electrical stimulation of the left stellate ganglion (LSG) can trigger ventricular arrhythmias (VAs) from the right ventricular outflow tract (RVOT).
• The role of pulmonary artery innervation in LSG-stimulated VAs remains unclear.

Purpose of the Study:

• To investigate the impact of selective pulmonary artery denervation (PADN) on blood pressure (BP), sympathetic activity, ventricular effective refractory period (ERP), and LSG-stimulated VAs in canines.
• To determine if PADN can reduce the incidence of VAs originating from the RVOT.

Main Methods:

• PADN was induced in canines using radiofrequency ablation.
• Measurements included heart rate variability, serum norepinephrine and angiotensin-II levels, BP, and ventricular ERP before and after PADN.
• VAs were induced by LSG stimulation in a canine model with complete atrioventricular block; pulmonary artery sympathetic nerves were immunohistochemically analyzed.

Main Results:

• PADN significantly decreased heart rate variability, serum norepinephrine and angiotensin-II levels, and mitigated LSG-induced systolic BP elevation and RVOT ERP shortening.
• The incidence, number, and duration of RVOT-VAs, including premature ventricular contractions and tachycardia, were significantly reduced post-PADN.
• Tyrosine hydroxylase-immunoreactive nerve fibers were abundant in the anterior wall of the pulmonary artery.

Conclusions:

• Pulmonary artery denervation (PADN) effectively ameliorated RVOT ERP shortening and reduced LSG-induced RVOT-VAs.
• PADN's anti-arrhythmic effects are attributed to the inhibition of cardiac sympathetic nerve activity.