Renal sympathetic denervation: A promising therapy for resistant hypertension

Despite rapid strides in pharmacotherapy for hypertension over last few decades, resistant hypertension continues to be prevalent. Activation of the sympathetic nervous system is an important etiological factor in the pathogenesis of hypertension and renal sympathetic nervous system is one of its pivotal arm. Thus, renal sympathetic system was the target of therapy for hypertension in the initial period, in the form of sympathectomy. The major adverse events associated with this procedure and the emergence of potent blood pressure (BP) lowering medications led to disrepute of this procedure. Of late, novel techniques targeting the sympathetic nervous system have emerged. Among them and the most promising one is catheter-based radiofrequency ablation of renal nerves-Renal sympathetic denervation (RSD). Clinical trials of renal denervation therapy have shown consistent and durable reduction of systolic as well as diastolic BP persisting up to 3 years. Beyond BP control, renal denervation also exerts favorable effects on glucose metabolism, heart failure, and sleep apnea. As many as five different catheter-based renal denervation systems are now approved for treating resistant hypertension, the maximum clinical experience being with Medtronic's symplicity system. The European Society of Cardiology guidelines for hypertension 2013 now recommend catheter-based renal denervation for management of drug-resistant hypertension. In this review, we briefly discuss the role of sympathetic nervous system in the pathogenesis of hypertension, the present status, and future perspectives of RSD in the treatment of resistant hypertension.