Attenuating Cardiac Sympathetic Tone via Cryoneurolytic Stellate Ganglion Ablation.

BACKGROUND

Stellate ganglion blockade provides temporary control of refractory ventricular arrhythmias by reducing sympathetic flow to the heart. However, current percutaneous approaches are limited by short duration of effect, creating a need for longer-lasting sympathetic modulation without more invasive permanent sympathectomy.

OBJECTIVE

To determine the efficacy and durability of stellate ganglion cryoneurolytic ablation in attenuating evoked cardiac sympathetic responses.

METHODS

We conducted acute cryoablation studies in 6 Yorkshire pigs and chronic studies in 10 Yucatan minipigs (7 cryoablation, 3 sham controls). Acute studies evaluated hemodynamic responses and myocardial norepinephrine release using fast-scanning cyclic voltammetry. Chronic studies assessed one-month physiological, electrophysiologic, neurochemical, and histologic effects following right stellate ganglion cryoneurolytic ablation.

RESULTS

Cryoneurolytic stellate ganglion ablation attenuated evoked cardiac sympathetic responses in both acute and chronic phases. One month following ablation, sympathetic attenuation persisted and was accompanied by significant treatment effects on ventricular repolarization. Sympathetic attenuation remained anatomically restricted to the ablation site, and targeting the T1 component of the stellate ganglion alone was sufficient to eliminate the majority of evoked sympathetic cardiac effects.

CONCLUSION

Cryoneurolytic stellate ganglion ablation effectively provides durable cardiac sympathetic modulation, offering a promising intermediate-duration treatment for refractory ventricular arrhythmias.