Renal Denervation by Ablation with Innovative Technique in Resistant Hypertension

Abstract

Hypertension is the cause of thousands of deaths annually1, and half of the patients treated present controlled blood pressure (BP)2. Resistant hypertension (RH)is defined when the BP remains above the recommended targets with the use of three antihypertensive drugs with synergistic actions at maximum doses recommended and tolerated, preferably one being a diuretic, or when in use of four or more anti-hypertensive drugs, even with controlled BP3. It is estimated that 12%-15% of persons with hypertension are considered resistant, with high risk of cardiovascular morbidity and mortality4. The pathogenesis of hypertension is multifactorial, but the sympathetic activity plays an important role, especially in patients with resistant hypertension2. Efferent renal sympathetic activity stimulates renin release, increases sodium reabsorption and reduces renal blood flow and may be a mechanism for the development and maintenance of hypertension2. Genetic, behavioral and environmental factors influence increased sympathetic activity in persons with hypertension5. New therapies aiming to reduce sympathetic activity have been developed. Renal Sympathetic Denervation (RSD) by radiofrequency catheter ablation of renal arteries has been shown to control BP in resistant hypertension6,7 and in associated clinical conditions such as sleep destructive apnea8 and insulin resistance9. The main RSD clinical studies used a specific catheter not yet available in Brazil, but the radiofrequency ablation of arrhythmias is a procedure that has been performed by electrophysiologists through appropriate catheters for years in our country. Experimental studies of RSD with catheters used for ablation of arrhythmias indicated the possibility of using these to replace those used in international studies, considering the unavailability of those in our reality. Based on this, for the procedure to be reported, the model used for ablation in children (4 mm tip and 5F), which was proven to be more appropriate, was chosen. The objective of the report is to show the result of the first RSD in our community, with the aid of technology used in cardiac arrhythmias.