Renal Denervation

Abstract

Renal sympathetic denervation is a novel and promising therapy option for patients with treatment-resistant primary arterial hypertension. By ablating renal sympathetic nerves in the wall of the renal artery, blood pressure decreases significantly without affecting renal function. This intervention is technically straightforward, and possible relevant procedure-specific complications are rare.

Extended indications are under investigation including milder forms of hypertension or heart failure. Future studies should reveal the full potential of this novel technique of blood pressure control possibly introducing renal sympathetic denervation into the clinical routine.

The kidney is an important player in blood pressure regulation. While the principles of blood pres­sure regulation by renin-angiotensin-aldosterone system, RAAS, have been to a large extent explored, the knowledge of blood pressure regulation via renal sympathetic innervation remains rudimentary. Nevertheless, it appears that continuously elevated renal sympathetic drive may be an important factor in the pathophysiology of arterial hypertension. In majority of these cases, antihypertensive drug regimes fail to lower blood pressure to target levels. Recently, reducing elevated (renal) sympathetic nerve activity by disrupting the interactions between the kidney and the sympathetic nervous system through catheter-based renal denervation has appeared as a potentially effective treatment option. The sympathetic renal nerves lie in the adventitia of the renal arteries approximately 3–4 mm abluminal, which makes them accessible for disruption by radiofrequency energy without any relevant collateral damage to the surrounding tissues. The endovascular concept of denervation of the renal sympathetic nerves includes the use of a radiofrequency catheter with a steerable electrode tip which is connected to a radiofrequency generator. Employing this novel endovascular technique, the early results in a limited number of patients showed a markedly improved blood pressure control in about 85% of treated patients [1].