From the Guidelines
Renal denervation may be considered for patients with resistant hypertension who have uncontrolled blood pressure despite treatment with at least three antihypertensive medications, including a diuretic, and who express a preference to undergo the procedure after a shared risk-benefit discussion and multidisciplinary assessment. This recommendation is based on the most recent guidelines from the European Heart Journal, which suggest that catheter-based renal denervation can be considered for resistant hypertension patients who meet specific criteria 1.
Patient Selection
When selecting patients for renal denervation, it is essential to consider the following factors:
- Confirmed resistant hypertension, defined as blood pressure remaining above 140/90 mmHg despite treatment with at least three antihypertensive medications at maximum tolerated doses, including a diuretic
- Normal renal artery anatomy
- Estimated glomerular filtration rate (eGFR) > 45 mL/min/1.73m²
- Patient preference to undergo renal denervation after a shared risk-benefit discussion and multidisciplinary assessment
Procedure and Effectiveness
The procedure involves using catheter-based radiofrequency ablation or ultrasound energy to disrupt the sympathetic nerves in the renal arteries, typically performed under local anesthesia and conscious sedation 1. Renal denervation can lead to significant blood pressure reductions in some patients, typically ranging from 5-20 mmHg systolic, although individual responses vary 1.
Safety and Follow-up
The procedure is generally safe, with a low risk of complications, including renal artery injury, bleeding, or infection 1. Patients should continue their antihypertensive medications after the procedure and be monitored regularly, as blood pressure reductions may not be immediate and can continue to improve over 3-6 months.
Justification
Renal denervation works by reducing sympathetic nervous system activity to the kidneys, which plays a role in regulating blood pressure, and is considered for patients who have not responded adequately to conventional treatments 1.
From the Research
Definition and Pathophysiology of Resistant Hypertension
- Resistant hypertension is defined as failure to control blood pressure <140/90 mmHg in an adherent non-diabetic patient with normal kidney function despite the use of optimal doses of three antihypertensive agents, including a diuretic 2.
- One of the most important pathophysiological mechanisms of resistant hypertension is overactivity of the sympathetic nervous system (SNS) 2.
Role of Renal Denervation in Treating Resistant Hypertension
- Renal denervation is a minimally invasive procedure that disrupts renal efferent and afferent neural connections, both of which are important regulators of BP control 3.
- Renal denervation has been shown to control blood pressure by suppressing SNS overactivity in selected patients with resistant hypertension 2.
- The procedure may improve 24-hour ambulatory blood pressure monitoring (ABPM) systolic and diastolic BP, as well as office diastolic BP, but has little or no effect on office systolic BP 4.
Efficacy and Safety of Renal Denervation
- There is low-certainty evidence that renal denervation does not improve major cardiovascular outcomes and renal function in patients with resistant hypertension 4.
- Moderate-certainty evidence exists that renal denervation may improve 24h ABPM and diastolic office-measured BP 4.
- The long-term efficacy and safety of this procedure, as well as the identification of responders and the underlying mechanisms, need to be addressed by ongoing and future trials 5.
Current Status and Future Directions
- Renal denervation remains an experimental procedure and should only be offered to truly resistant hypertensive patients in a research context after careful selection 5.
- Future trials measuring patient-centred instead of surrogate outcomes, with longer follow-up periods, larger sample size, and more standardized procedural methods are necessary to clarify the utility of this procedure in this population 4.