Heart, Lung and Circulation

Renal Denervation for Refractory Hypertension

      Background: Sympathetic activation is a cardinal feature of chronic renal failure (CRF) and contributes to poor cardiovascular outcomes. Both efferent and afferent renal nerves play a crucial role in blood pressure regulation and hypertension commonly associated with CRF. Renal nerve ablation has been shown to be safe and effective in patients with resistant hypertension with normal renal function. Whether this approach is safe and effective in hypertensive patients with an eGFR below 45 ml/min has not yet been explored.
      Methods: In this pilot study, percutaneous endovascular radiofrequency ablation was performed in three hypertensive patients (age 67 ± 1 years) with CRF stage 3–4 (mean baseline eGFR 29.7 ± 3.8 ml/min). To reduce contrast exposure CO2-angiography was used to visualise the renal arteries and to position the ablation catheter. Standardised office blood pressure (BP) readings and serum biochemistry were obtained before and 1, 7, and 28 days after the procedure.
      Results: Mean baseline BP was 192 ± 29/91 ± 18 mm Hg despite an average of 5.3 antihypertensive drugs. Each patient underwent treatment of both renal arteries in one session with an average of 4.2 ± 0.8 ablation treatments per artery. Angiographic evaluation before and directly after the procedure did not reveal any compromise of the treated arteries. There were no intra- or periprocedural complications. At seven day and 28 day follow up estimated GFR was 27.7 ± 6.0 and 27.7 ± 5.5 ml/min, and average BP was 179 ± 11/86 ± 15 and 163 ± 38/82 ± 25 mm Hg, respectively.
      Conclusions: Our preliminary findings are indicative of a favourable short term safety profile and a rapid blood pressure response to renal denervation in high risk patients with CRF.