Renal Denervation: What is it and when to treat it?
The Renal Denervation (RDN) is a catheter procedure performed in a Cath Lab, through the use of a special catheter that utilizes radiofrequency energy to cauterize the nerves innervating the renal arteries. This technique is performed by Interventional Cardiologists trained for this purpose. It is performed to the sedated patient with the aid of an Anesthesiologist. The catheter currently available more used is the Simplicity manufactured by Medtronic, allowing us to perform between 3 to 5 radiofrequency applications for 2 minutes on each renal artery greater than 4 mm in diameter and 20 mm in length. RF applications are about 5 mm distance between each other being the most important the one applied at the ostium and upper face of each renal artery. This procedure is applied on patients with resistant arterial Hypertension. That is, in those who a secondary cause of hypertension have been ruled out and have also been excluded from Renovascular Hypertension diagnosis. In this regard it is important that the patient gets a Normal Renal Doppler Ultrasound prior to the procedure of RDN. Conducting a Blood Pressure Holter or 24-hour ABPM is also a prerequisite before the procedure. To categorize a patient with resistant hypertension, they must be taking at least 3 antihypertensive drugs, one of which should be a diuretic, which must necessarily block the renin-angiotensin-aldosterone system (specifically spironolactone), also it must be shown that the blood pressure in the doctor’s office is greater than 160/90 mmHg, or otherwise inadequate ABPM must be demonstrated by ambulatory monitoring of blood pressure.
