Opportunities and Limitations of Renal Denervation: Where Do We Stand?

Hypertension is a primary contributor to cardiovascular disease, and the leading risk factor for loss of quality adjusted life years. Up to 50% of the cases of hypertension in the US remain uncontrolled. Additionally, 8-18% of the hypertensive population have resistant hypertension, uncontrolled pressure despite three different anti-hypertensive agents. Recently, catheter-based, percutaneous renal denervation emerged as a method for ablating renal sympathetic nerves for difficult to control hypertension. Initial randomized (non-sham) trials and registry analyses showed impressive benefit, but the first sham-controlled randomized controlled trial (RCT) using monopolar radiofrequency ablation showed limited benefit. With refinement of techniques to include multipolar radiofrequency, ultrasound denervation, and direct ethanol injection, RCTs demonstrated significant blood pressure improvement, leading to FDA approval of radiofrequency and ultrasound-based denervation technologies. In this review article, we summarize the major randomized sham-controlled trials and societal guidelines regarding the efficacy and safety of renal artery denervation for the treatment of uncontrolled hypertension.