Implanted device could help patients with resistant high blood pressure
25 January 2015
A novel device is able to lower blood pressure significantly among patients with uncontrolled high blood pressure, compared to those on drug treatments.
The ROX Coupler shown lower left. Photo courtesy of the research group
The device – developed by ROX Medical and named the ‘Coupler’ – is a paper clip sized implant which is inserted between the artery and vein in the upper thigh, in a procedure lasting around 40 minutes under local anaesthetic.
Researchers, led by Queen Mary University, London carried out a randomised, blinded endpoint clinical trial with patients from multiple European Centres of Hypertension all of whom had resistant high blood pressure and had not responded to at least three types of drug treatment.
The University of Leicester and NIHR Leicester Cardiovascular Biomedical Research Unit, based at Glenfield Hospital, actively participated in this trial, identifying that there was a clear unmet need with current therapies to manage patients with treatment resistant hypertension.
The results from this trial demonstrated a statistically significant improvement in all measures of blood pressure monitoring (Office BP, Ambulatory BP and Home BP). In addition, the number of hypertensive complications and hospital admissions for high blood pressure were significantly reduced in the treatment arm
Professor Andre Ng, Professor of Cardiac Electrophysiology at the University of Leicester and Consultant Cardiologist at Leicester’s Hospitals, who is Principal Investigator at the University of Leicester said the results of the trial give promise to this completely new modality of treatment in patients with hypertension whose blood pressure remains uncontrolled despite three or more medications.
"The treatment involves inserting the ROX-coupler device (like a small metal stent) between the artery and the vein at the top of the leg," Professor Ng explains. "The concept is similar to relieving the high pressure within a closed central heating system.”
The implant is inserted between the artery and vein in the upper thigh (illustration courtesy of the research group)
ROX Medical’s FLOW procedure is a relatively painless, minimally invasive, percutaneous procedure to insert the AV Coupler in the upper leg. The AV-Coupler maintains a stable, fixed opening between the artery and vein thereby restoring compliance in the great vessels.
This unique mechanism of action provides for a safe, significant and durable reduction in blood pressure and may provide a treatment option for people with hypertension associated with arterial stiffening. The FLOW procedure only involves the vascular structure, has an immediate effect and is fully reversible.
However, the Coupler, like all therapies, does have a side effect. Around 29 percent of patients who received the Coupler did go on to develop leg swelling which meant another short procedure was needed to deal with this (usually a stent in the vein).
The study, published in The Lancet, was funded by ROX Medical.
The ROX FLOW procedure for hypertension is not approved for use in the USA.