TCT-12 Long-term Follow-up of Catheter-based Renal Denervation For Resistant Hypertension Confirms Durable Blood Pressure Reduction

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.