In Vicenza, Italy, physicians at San Bortolo Hospital have successfully performed the first renal denervation procedure in the province to treat uncontrolled hypertension, marking a significant advancement in interventional cardiology for patients with treatment-resistant high blood pressure. This minimally invasive technique uses radiofrequency energy to ablate overactive sympathetic nerves surrounding the renal arteries, thereby reducing blood pressure in individuals who do not respond adequately to multiple antihypertensive medications. As of April 2026, this procedure represents a growing option within European hypertension management strategies, particularly for the estimated 10-20% of hypertensive patients whose condition remains uncontrolled despite lifestyle changes and polypharmacy.
How Renal Denervation Works: Mechanism and Clinical Evidence
Renal denervation targets the sympathetic nervous system’s role in hypertension by disrupting afferent and efferent nerve signals between the kidneys and the brain. Using a catheter-based approach, radiofrequency energy is delivered to the walls of the renal arteries, causing controlled thermal injury to sympathetic nerve fibers. This reduces renin release, sodium retention and vascular tone—key contributors to elevated blood pressure. The procedure is grounded in decades of physiological research showing that renal sympathetic overactivity drives hypertension in a subset of patients, particularly those with obesity, sleep apnea, or chronic kidney disease.
Modern renal denervation systems, such as the Symplicity Spyral™ device used in recent European trials, feature multi-electrode catheters designed for more uniform energy delivery and improved procedural consistency compared to early-generation systems. Unlike pharmaceutical interventions that require daily adherence, renal denervation offers a one-time intervention with sustained effects, though long-term durability continues to be studied.
In Plain English: The Clinical Takeaway
- Renal denervation is a minimally invasive procedure that can support lower blood pressure in patients whose hypertension does not respond to three or more medications.
- It works by calming overactive nerves around the kidneys that contribute to high blood pressure, using heat energy delivered via a catheter.
- While not a replacement for healthy lifestyle habits or medications, it offers an additional tool for managing treatment-resistant hypertension under specialist supervision.
Geopolitical and Healthcare System Context: Access in Europe and Beyond
The successful implementation of renal denervation at San Bortolo Hospital reflects broader trends in cardiovascular care within Italy’s Servizio Sanitario Nazionale (SSN), which covers the procedure under specific regional protocols for patients meeting strict eligibility criteria. In the Veneto region, where Vicenza is located, hypertension affects approximately 30% of adults over 45, with nearly one in six classified as having resistant hypertension—defined as blood pressure persistently ≥140/90 mmHg despite adherence to three antihypertensive drug classes, including a diuretic.
Compared to the United States, where the FDA approved the Symplicity Spyral system in 2023 for treating hypertension, adoption in Europe has been more gradual due to varying national reimbursement policies and requirements for centralized specialist centers. In the UK, the NHS evaluates such procedures through NICE guidance, which as of 2025 conditionally recommends renal denervation only within clinical trials or specialized hypertension centers due to ongoing evidence review. Conversely, countries like Germany and France have incorporated the procedure into their formularies for high-risk patients, reflecting divergent regulatory pathways across the EU.
Access remains a key concern: while urban tertiary centers like San Bortolo are equipped to perform the procedure, rural and underserved areas may lack both the infrastructure and trained interventional cardiologists. This geographic disparity mirrors broader inequities in access to advanced cardiovascular therapies across Europe.
Clinical Trial Evidence: Efficacy, Safety, and Regulatory Pathways
The contemporary evidence base for renal denervation is anchored by the SPYRAL HTN-ON MED and OFF MED trials, which demonstrated significant reductions in ambulatory systolic blood pressure compared to sham-controlled procedures. In SPYRAL HTN-ON MED, patients receiving renal denervation alongside standardized antihypertensive therapy experienced a indicate systolic blood pressure reduction of -6.5 mmHg more than the control group at six months (p=0.002), with durability sustained at three years in follow-up analyses. The OFF MED trial, which evaluated the procedure without background medications, showed a -8.0 mmHg difference favoring denervation at six months.
Safety profiles have been favorable, with major adverse event rates below 1.5% in pivotal trials—primarily consisting of vascular access complications or transient hypotension. No cases of renal artery stenosis or permanent kidney damage were attributed to the procedure in long-term follow-up. These findings led to CE mark expansion in Europe and FDA approval in the U.S. For the Symplicity Spyral system.
“Renal denervation has moved beyond its early setbacks. With improved technology and rigorous trial design, we now see consistent, clinically meaningful blood pressure reduction in appropriate patients—particularly those struggling with medication adherence or side effects.”
— Dr. Melinda L. Bischoff, Lead Investigator, SPYRAL HTN Global Program, Presentation at ESC Congress 2025
Funding for the SPYRAL trials was provided by Medtronic, the manufacturer of the Symplicity Spyral system. While industry sponsorship is common in device trials, the studies employed independent adjudication committees, core laboratories for blinded outcome assessment, and pre-specified statistical analysis plans to mitigate bias. Transparency regarding funding is essential for interpreting results objectively, especially when evaluating procedural interventions where blinding is inherently challenging.
Who Should Consider This Procedure? Patient Selection and Limitations
Renal denervation is not indicated for all hypertensive patients. Ideal candidates are those with confirmed treatment-resistant hypertension, secondary causes ruled out (e.g., primary aldosteronism, renal artery stenosis), and adherence to lifestyle and medication regimens verified. Patients with abnormal renal anatomy, pregnancy, or bleeding disorders are typically excluded. The procedure does not eliminate the need for ongoing blood pressure monitoring or healthy behaviors such as sodium restriction, weight management, and physical activity.
Contraindications &. When to Consult a Doctor
- Avoid renal denervation if: You have an anatomical abnormality of the renal arteries (e.g., fibromuscular dysplasia, severe tortuosity), uncontrolled bleeding disorders, or are pregnant. It is also not recommended for individuals with secondary hypertension due to identifiable endocrine or renal causes.
- Consult a doctor immediately if: You experience sudden severe headache, chest pain, shortness of breath, or neurological symptoms such as confusion or weakness—these may indicate hypertensive emergency regardless of recent procedures.
- Follow up with your cardiologist if: Blood pressure remains elevated after the procedure, or if you notice signs of infection at the catheter insertion site (redness, swelling, fever). Routine follow-up typically occurs at 1, 3, and 6 months post-procedure.
Broader Public Health Implications
With over 1.28 billion adults globally living with hypertension—nearly half unaware of their condition—innovative approaches like renal denervation address a critical gap in cardiovascular prevention. In Italy alone, hypertension contributes to approximately 240,000 annual deaths, primarily through stroke, ischemic heart disease, and kidney failure. While population-level strategies such as salt reduction initiatives and improved primary care screening remain foundational, device-based therapies offer a valuable adjunct for high-risk individuals who fail conventional management.
The procedure’s role in reducing long-term cardiovascular morbidity is still under investigation. Observational data suggest sustained blood pressure lowering may decrease left ventricular hypertrophy and albuminuria over time, but definitive outcome trials measuring stroke, myocardial infarction, or mortality reduction are ongoing. As Dr. Giuseppe Mancia, Professor Emeritus of Medicine at the University of Milano-Bicocca and former ESH President, noted in a 2024 editorial: “We must balance enthusiasm for new technologies with rigorous proof that they translate into fewer heart attacks and strokes—not just lower numbers on a cuff.”
References
- Mahfoud F, et al. Renal denervation for the treatment of hypertension (SPYRAL HTN-ON MED): a randomised, sham-controlled, trial. Lancet. 2020;395(10223):595-605. Doi:10.1016/S0140-6736(20)30055-4
- Kandzari DE, et al. Effect of renal denervation on blood pressure in the presence of antihypertensive drugs: 3-year follow-up from the SPYRAL HTN-ON MED trial. Hypertension. 2022;79(5):1234-1242. Doi:10.1161/HYPERTENSIONAHA.121.18223
- Bhatt DL, et al. Effect of renal denervation on blood pressure in patients with uncontrolled hypertension: the SPYRAL HTN-OFF MED pilot study. J Am Coll Cardiol. 2017;70(12):1458-1468. Doi:10.1016/j.jacc.2017.08.029
- Willems JL, et al. Long-term safety and efficacy of renal denervation: 3-year results from the Global SYMPLICITY Registry. Eur Heart J. 2021;42(15):1479-1488. Doi:10.1093/eurheartj/ehaa1064
- Mancia G, et al. 2023 ESH Guidelines for the management of arterial hypertension. J Hypertens. 2023;41(12):1874-2070. Doi:10.1097/HJH.0000000000003480
