Transvenous microwave aorticorenal ganglion ablation improves renal denervation outcomes.

BACKGROUND

Aorticorenal ganglia (ARG) serve as critical sympathetic relay centers for renal innervation, and their targeted ablation represents a promising alternative to conventional renal artery denervation by enabling precise disruption of renal sympathetic outflow through a transvenous approach.

OBJECTIVE

To test feasibility and efficacy of sympathetic renal denervation (RDN) by targeting ARG using microwave (MW) catheter from inferior vena cava (IVC) in addition to conventional transarterial MW denervation and assess ARG localization in humans using pacing-induced physiological responses.

METHODS

Pigs underwent sham ( n  = 8), renal denervation (RDN; n  = 7), or RDN plus ARG ablation (RDN + ARG; n  = 7) using custom open-irrigated microwave catheter. Baseline ARG pacing caused renal vasoconstriction and raised mean arterial pressure (MAP). RDN and RDN + ARG groups received one ablation in each main renal artery (100-120 W, 360 s); RDN + ARG also had ARG ablation. After 4-5 weeks, ARG pacing was repeated before euthanasia. In humans ( n  = 3), high-frequency pacing in IVC and renal veins identified ARG capture sites, guided by MRI and electroanatomical mapping.

RESULTS

ARG ablation modified pacing responses acutely sustained at 4-5 weeks, with preservation of blood pressure response but significant loss of renal vasoconstriction. Compared to undenervated shams, RDN+ARG vs. RDN reduced viable nerve area by 76% vs. 54% and renal cortical norepinephrine by 51% vs. 15%. In humans, ARG stimulation increased MAP from 108.9 to 123.2 mmHg.

CONCLUSIONS

ARG ablation, when combined with conventional RDN, achieves greater efferent renal sympathetic denervation in pigs. In humans, analogous sites were identified showing pacing-induced hemodynamic responses consistent with ARG.