Increasing the coverage length of catheter-based renal denervation by 40% significantly increased norepinephrine reduction to 78% and affected nerves to 58% (p=0.05), comparable to surgical denervation.
Does increasing the length coverage of catheter-based renal denervation improve kidney tissue norepinephrine reduction and nerve ablation in juvenile Yorkshire swine?
In a preclinical swine model, increasing the longitudinal coverage of renal denervation significantly improved sympathetic nerve ablation efficacy compared to increasing circumferential coverage alone.
valor p: p=0.05
Background: Catheter-based percutaneous renal denervation (RDN) has shown durable reductions of blood pressure in patients with uncontrolled hypertension. The importance of applying circumferential denervations inside the renal arteries is known to contribute to efficacy; however, the significance of denervations along the entire renal artery length is yet to be appreciated. Methods: We used the V2 SystemTM (Vessix Vascular Inc., Laguna Hills, CA) for the renal denervation procedures. The V2 System consists of a proprietary bipolar RF generator and an over-the-wire low pressure balloon catheter with an array of radiofrequency (RF) electrodes mounted on the exterior in an offset helical pattern. Each temperature controlled dose (68°C) of bipolar energy is delivered for 30 seconds. A total of 15 juvenile Yorkshire swine were treated bilaterally (n 3 in each group, see table). Efficacy was evaluated at 14 days post treatment using an HPLC-MS/MS method to measure kidney tissue norepinephrine (NEPI). In addition, histopathologic methods were used to assess the percentage of affected nerves. Results: A single V2 treatment per artery with 95% circumferential coverage and 60% length coverage (21 mm) was applied resulting in 40% of nerves being affected and a NEPI reduction of 46% when compared to control group endogenous level. Increasing the circumferential coverage by 35% did not change efficacy. However, increasing coverage length by 40% significantly increased NEPI reduction to 78% and significantly increased the percentage of affected nerves to 58% (p 0.05) and was comparable to surgical denervation.
Krum et al. (Mon,) conducted a other in Resistant Hypertension (n=15). Catheter-based renal denervation (V2 System) vs. Control group endogenous level and surgical denervation was evaluated on Kidney tissue norepinephrine (NEPI) reduction and percentage of affected nerves (p=0.05). Increasing the coverage length of catheter-based renal denervation by 40% significantly increased norepinephrine reduction to 78% and affected nerves to 58% (p=0.05), comparable to surgical denervation.