Radiofrequency and Irrigated Ablation: Principles and Potential for Renal Artery Denervation (RDN) in the Treatment of Resistant Arterial Hypertension

Renal artery denervation (RDN) represents a relatively new technique for treating patients whose arterial hypertension persists despite three or more antihypertensive medications [1]. The main principle underlying RDN dates back 50 years or more and gave rise to surgical sympathectomy procedures [2]. Radiofrequency (RF) catheter ablation is a therapeutic procedure that delivers a controlled source of energy in order to create a lesion at the site of the target tissue. Lesion formation is restricted to a limited volume of tissue close to the ablation electrode. Since this technique was first introduced, it has become one of the most useful and widely accepted therapies in the field of cardiac electrophysiology, later followed by application in renal denervation procedures. Modifications in RF delivery and improvements in electrode design have resulted in a significant expansion of its indication such as chronic kidney disease (CKD), arrhythmias, obstructive sleep apnoea and glucose control [3, 4].