Renal denervation in the antihypertensive arsenal – knowns and known unknowns

Abstract

Even though it has been more than a decade since renal denervation (RDN) was first used to treat hypertension and an intense effort on researching this therapy has been made, it is still not clear how RDN fits into the antihypertensive arsenal. There is no question that RDN lowers blood pressure (BP), it does so to an extent at best corresponding to one antihypertensive drug. The procedure has an excellent safety record. However, it remains clinically impossible to predict whose BP responds to RDN and whose does not. Long-term efficacy data on BP reduction are still unconvincing despite the recent results in the SPYRAL HTN-ON MED trial; experimental studies indicate that reinnervation is occurring after RDN. Although BP is an acceptable surrogate endpoint, there is complete lack of outcome data with RDN. Clear indications for RDN are lacking although patients with resistant hypertension, those with documented increase in activity of the sympathetic system and perhaps those who desire to take fewest medication may be considered.

Medical Measures in Hypertensives Considered Resistant

“…RDN seems to lower BP on average equally to 1 antihypertensive drug. 30 Still, long-term BP reduction data are at best uncertain. 31 Long-term data from the rather small Oslo RDN study indicate no difference in BP reduction between RDN and optimized pharmacotherapy alone, and these results provide the longest follow-up reported after RDN.…”

The Next Chapter of Renal Denervation After US Food and Drug Administration Approval

“…Despite the potential differences in efficacy in some subgroups of patients, both RF-based and ultrasoundbased RDN have been shown to be remarkably safe because the rates of serious adverse events, including access site (groin) complications, renal artery dissection, renal artery stenosis, were all <1% across all major clinical trials. 4,6 Given the invasive nature of RDN, the anticipated cost, and modest efficacy in reducing ambulatory SBP of 4 to 6 mm Hg (equivalent to 7-10 mm Hg reduction in office SBP often observed with addition of 1 antihypertensive drug), 11 this technology should not be used for all hypertensive patients. In addition, the cost-effectiveness of RDN in the United States remains unknown until the cost of device and procedure versus the potential cost of saving from less medication intensification and cardiovascular protection in diverse populations is established.…”

Sympathetic Pathophysiology in Hypertension Origins: The Path to Renal Denervation

“…Several open questions remain to be addressed to fully appreciate the factors influencing the BP-lowering efficacy of RDN, as summarized recently. 86 As a therapy directly targeting sympathetic overactivity, RDN may provide additional benefit in many conditions characterized by heightened sympathetic tone, such as those depicted in Figure 6. Exploration of the full potential of RDN in cardiovascular medicine can now be undertaken.…”

“…Several open questions remain to be addressed to fully appreciate the factors influencing the BP-lowering efficacy of RDN, as summarized recently. 86…”