A New Procedure, But for Whom?
Before percutaneous renal denervation, an irreversible intervention, is held up to universal acclaim, further questions ought to be clarified. These include the patients in whom a lasting effect can be expected (are renin readings  expedient?) and the risks to kidney function (e.g. due to cholesterol embolization). Figure 2 suggests, with a decreasing number of cases, that for two years after surgery there is an increasing effect in reducing blood pressure when compared to the subgroups used in the original publication (2). eGFR (estimated glomerular filtration rate) was recorded in only a few patients and fell significantly over two years. The procedure is not evaluated, or apparently not suitable, for patients with advanced renal failure, those requiring dialysis, or kidney transplant recipients, in whom resistance to treatment is common. For these patients, information on existing treatment options would be valuable. The table „Drug treatment....“ is confusing: no superiority of aliskiren over other renin-angiotensin system inhibitors in reducing blood pressure is evidence- based, alpha-1-receptor-blockers and alpha-blockers are identical, doxazosin is not included, and endothelin antagonists are not approved for the treatment of arterial hypertension. Also omitted is the outstanding importance of salt-water balance (3) in resistance to treatment, by taking into consideration diet, duration of drug effects, and patients` renal function. Low doses of aldosterone antagonists are administered for primary hypertension in addition to another diuretic. Of all the above-mentioned substances, the greatest and most reliable antihypertensive effect is that of minoxidil, although minoxidil has multiple side effects. With these caveats in mind, it cannot be disputed that renal denervation may extend the range of antihypertensive tools available. However, pharmacological options should be fully explored before intervention. The trials at hand also show that antihypertensive medication needs to be taken even after renal denervation.
Prof. Dr. med. Manfred Anlauf
Prof. Dr. med. Franz Weber, St. Walburga-Krankenhaus, Meschede
Conflict of interest statement
Prof. Anlauf holds shares in Astella Pharma and Novartis.
Prof. Weber has received fees for preparing scientific continuing education events from Daiichi Sankyo and Fresenius.
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