New results from a recent study led by researchers at New York-Presbyterian and Columbia University reveal that brief pulses of ultrasound delivered to nerves near the kidney produce a clinically meaningful reduction in blood pressure in patients whose hypertension did not respond to a triple cocktail of medications.
The clinical trial tested a novel ultrasound therapy for hypertension based on an old hypothesis that disrupting signals from overactive renal nerves can lower systemic blood pressure. The concept is called renal denervation, and it goes back over five decades.
Some currently available medications for hypertension work by this technique of reducing renal nerve activity. About two-thirds of people that take medicines can get a grip on their condition. However, the medications don’t work for everyone, or individuals don’t take them as directed.
Ajay Kirtane, MD, a co-principal researcher in the trial, said:
There are various effective medications for lowering blood pressure, but many people need to take several drugs to control their hypertension, which can have side effects. In addition, many people don’t want to take additional medications and are poorly adherent to them. It’s clear that we need additional therapeutic approaches to help patients get their blood pressure under control.
So, numerous scientists have long worked to locate a non-pharmacological method to target this mechanism.
Kirtane continued:
Unlike medications, which are only effective when you take them, renal denervation is a therapy that’s always ‘on.’
Renal denervation is a minimally invasive procedure. It involves threading a catheter up to the renal arteries through an artery in the leg. Then, a doctor uses ultrasound power to disrupt signals from overactive nerves within the renal arteries.
Kirtane said:
For patients with drug-resistant hypertension, a drop in blood pressure of eight points – if maintained over longer-term follow-up – is almost certainly going to help reduce the risk of heart attack, stroke, and other adverse cardiac events.
The procedure hasn’t yet been authorized for medical usage by the FDA. Further follow-up will monitor the present trial for five years to analyze its long-lasting efficacy. Additional studies are still essential to test the procedure in other patient populations before broader approvals. Nevertheless, the researchers are hopeful.
Kirtane concluded:
These results suggest that renal denervation has the potential to become an important add-on to medication therapy – including for those who have difficulty managing several medications to control their hypertension. Additional studies will be needed to determine if this therapy may be effective for other groups, including older patients with hypertension and those with chronic kidney disease.
For now, the therapy remains experimental and only available through clinical trials.
