Renal denervation: Bridging specialty boundaries with better collaborations

Wei Li (Syracuse VA Medical Center, SUNY Upstate Medical University Syracuse, USA, and Texas Tech University School of Medicine, Lubbock, USA) and Aiyu Zhao (Syracuse VA Medical Center, Syracuse, USA) write together about the origins of renal denervation (RDN), the complications and challenges that can often accompany the new therapeutic intervention, and the importance of multidisciplinary collaboration to combat these issues effectively.

Hypertension leads to stroke, heart attack, heart failure, kidney damage, and many other health problems. A reduction of 10mmHg in systolic blood pressure (SBP) is associated with substantial risk reductions: 28% for heart failure, 27% for stroke, 17% for coronary disease, 5% for chronic kidney failure, and 13% for mortality.¹ In the USA, despite the availability of medications and lifestyle intervention advocacy, nearly 50% of adults are affected by hyper­tension.^2,3 The US Surgeon General’s call-to-action has underscored the role of social and economic factors as root causes of health inequities, notably impacting certain populations, including non-Hispanic Blacks and US veter­ans, who experience hypertension prevalence rates rang­ing from 71% to 87%.⁴ Among them, a majority (66%) were considered to have uncontrolled hypertensions, accord­ing to the Veterans Health Administration guideline.^2,4

The concept of RDN originated in 1953 with open surgical splanchnicectomy for severe primary hyperten­sion.⁵ The initial generation of minimally invasive cathe­ter-based RDN in 2014 failed to show significantly lower office or 24-hour ambulatory systolic blood pressure (SBP) compared with sham treatment.⁶ However, with further animal and clinical studies, two newer generation of percutaneous endo­vascular RDN devices have recently demonstrated that RDN significantly reduced office and 24-hour ambulatory blood pressure (BP) compared with sham treatment and subsequently received US Food and Drug Administration (FDA)’s approvals in November 2023.

Initially explored within interventional cardiology, RDN is now garnering interest from a broader range of medical specialties, including nephrology, radiology, and vascu­lar surgery. Each specialty contributes unique perspec­tives and expertise to RDN. Cardiologists provide insights into hypertension’s cardiovascular implications, while nephrologists offer valuable insights into renal physiology and blood pressure regulation, and have suggested that adults with hypertension and chronic kidney disease be treated with a lower target SBP of <120mmHg.⁷ Interventional cardiologists, radiologists, and vascular surgeons play pivotal roles in RDN’s image-guided procedures.

Like any other minimally invasive technologies, RDN poses challenges and potential complications, especially when intervening in normal renal arterial anatomies, often in working-age patients. Variations like accessory renal arteries or aberrant branching patterns can compli­cate procedures, increasing the risk of adverse events such as renal artery dissections, occlusions, perfora­tions, and bleeding. These complications may lead to life-threatening sequelae, necessitating open surgical reconstructions.

To mitigate challenges and minimise adverse events, implementing RDN programmes through a collaborative care models is key. Multidisciplinary teams, including physicians and allied healthcare professionals, should collaborate to assess patient suitability and care prior­ity, perform RDN procedures, and coordinate post-pro­cedural care. This patient-centred approach leverages diverse expertise to optimise treatment outcomes and evaluate long-term efficacy.

Given the developmental journey of the current RDN technology, it certainly serves as a catalyst opportunity for interdisciplinary research and future innovation, stimulating cross-specialty dialogue and collaboration. Cross-specialty joint research initiatives can explore the mechanistic underpinnings of RDN, elucidating its effects on sympathetic tone, renal function, and cardiovascular outcomes. Collaborative efforts also extend beyond clin­ical research to encompass technological advancements, such as smaller profiles of delivery systems, less invasive imaging modalities, and biomarker discovery, aimed at optimising RDN procedures and patient selection criteria.

RDN is within the realm of endovascular intervention where the adoption of RDN necessitates comprehensive education and training programmes spanning the above specialties. Collaborative efforts in medical education empower practitioners to further standardise the train­ings of RDN procedures. Furthermore, interdisciplinary training programmes foster a culture of mutual learning and collaboration, equipping healthcare professionals with a holistic understanding of RDN’s clinical applica­tions and implications across these specialties.

While RDN holds promise, its adoption may exac­erbate the above existing health inequities among the current hypertension populations due to disparities in access to care, socioeconomic factors (such as private or government/public health insurances), and geographic locations. Vulnerable groups may face barriers to access­ing this advanced therapeutic option for uncontrolled primary hypertension. Addressing these factors requires a multifaceted approach involving healthcare provid­ers, community stakeholders, and policy and law makers to ensure equitable access to RDN and comprehensive hypertension management among underserved and vulnerable populations, including veterans.

Overall, RDN represents more than just a new thera­peutic intervention; it embodies a major paradigm shift towards collaborative care delivery that affects one of the most prevalent health issues. By uniting specialists across disciplines, RDN will likely exemplify the transforma­tive power of interdisciplinary collaboration in advanc­ing medical science and improving patient outcomes in general. As we embrace the opportunities presented by RDN, let us continue to foster collaborative endeavours that transcend disciplinary boundaries and drive innova­tion in cardiac, imaging/radiological, vascular, and renal medicines.

Affiliations and disclosures: 

Wei Li is an associate professor and endovascular and vascular surgeon and the founding programme direc­tor of a surgeon-led future interventional nephrology fellowship programme. He is also a consultant for W. L. Gore & Associates, the principal investigator of studies at Becton, Dickinson, and Company (BD) and Recor Medical. Aiyu Zhao is a chief of nephrology, dialysis program medi­cal director, and facility dialysis programme committee chair, and board-certified hypertension specialist (CHS). She has no relevant financial disclosures.

 References

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