Beta radiation for renal nerve denervation: initial feasibility and safety

Area of Science:

• Cardiovascular Research
• Interventional Cardiology
• Nephrology

Background:

• Radiofrequency (RF) sympathetic renal denervation shows potential for resistant hypertension but involves lengthy, painful procedures.
• Vascular brachytherapy is effective for in-stent restenosis and may induce nerve fibrosis.

Purpose of the Study:

• To evaluate the safety and feasibility of using renal artery brachytherapy for sympathetic renal denervation.

Main Methods:

• Ten normotensive swine received vascular brachytherapy in renal arteries at 25 Gy or 50 Gy doses.
• Control arteries were untreated.
• Follow-up included angiography, intravascular ultrasound, and histopathology at one or two months.

Main Results:

• The procedure was safe, with no angiographic or ultrasound vessel injuries.
• Histology revealed thermal injury, more pronounced at 50 Gy.
• Nerve injury was observed, with a dose-dependent effect on severity.
• Minor endothelial cell loss (2-20%) was noted in arterioles.

Conclusions:

• Renal nerve denervation via low-to-intermediate dose beta-radiation is feasible and safe.
• This approach can induce renal nerve fibrosis without significant renal artery damage.