Renal denervation found to lower blood pressure in hypertensive patients
Endovascular ultrasound renal denervation, a surgery that targets the nerves connected to the kidney, was found to be beneficial for reduction of ambulatory blood pressure in hypertension patients in the absence of medications as compared to a sham procedure, according to a new study published in the journal The Lancet and presented at the EuroPCR congress in Paris.
The study was conducted by Melvin Lobo, from Queen Mary University of London, and colleagues to determine whether an alternative technology using endovascular ultrasound renal denervation reduces ambulatory blood pressure in patients with hypertension in the absence of antihypertensive medications.
Early studies suggest that radiofrequency-based renal denervation is relevant for reduction of blood pressure in patients with moderate hypertension.
Renal denervation (RDN), is a minimally invasive, endovascular catheter-based procedure using radiofrequency ablation or ultrasound ablation. Nerves in the renal artery wall are ablated by applying ultrasound or radiofrequency pulses to the renal arteries. This causes reduction of sympathetic efferent and afferent activity to the kidney resulting in the reduction of blood pressure.
The multicentre, international, single-blind, randomised, sham-controlled clinical trial was carried out from 2017 to 2018 at St Bartholomew's Hospital in the UK by the NIHR Barts Biomedical Research Centre, tested a one-hour operation called 'renal denervation.
146 patients in the United States, France, Germany, the Netherlands, Belgium and the United Kingdom were randomized to receive either renal denervation or a 'sham procedure' - the surgical equivalent of a placebo. Patients also remained off blood pressure medications for two months unless specified blood pressure levels were exceeded.
- After two months, the renal denervation group experienced an 8.5 mm Hg reduction in blood pressure, which was a 6.3 mm Hg greater reduction compared with the sham group.
- More than 66 percent of subjects treated with renal denervation demonstrated a 5 mm Hg or greater reduction in blood pressure, compared with 33 percent in the sham group.
- No major adverse events were reported in either group, and the blood pressure lowering effect of renal denervation was consistent across sex and ethnicity.
"These results leave us clinicians in no doubt that this ultrasound-based therapy works to improve blood pressure control - at least in the short term. Further larger trials will be needed to confirm the efficacy and safety of the technology, but we hope that they could lead to renal denervation therapy being offered as an alternative to lifelong medications for hypertension", said Dr. Lobo.
If the findings are confirmed in more extensive clinical trials, the surgery could offer hope to patients with high blood pressure who do not respond to drugs and are at increased risk of cardiovascular diseases, including stroke and heart attack.
"Compared with a sham procedure, endovascular ultrasound renal denervation reduced ambulatory blood pressure at 2 months in patients with combined systolic-diastolic hypertension in the absence of medications. However, Longer follow-up of this trial and additional numbers of treated patients will be necessary to provide greater assurance of safety and to exclude rare adverse events," concluded the authors.
For further information click on the link: https://doi.org/10.1016/S0140-6736(18)31082-1