A one-off operation that targets the nerves connected to the kidney has been found to maintain reduced blood pressure in hypertension patients for at least six months, according to the results of a clinical trial led in the UK by Queen Mary University of London and Barts Health NHS Trust, and supported by the National Institute for Health Research (NIHR).
The study, published in the journal Circulation and presented at the American College of Cardiology Conference in New Orleans, USA, also found that the patients treated with the procedure required fewer blood pressure medications.
If the findings are confirmed in larger and longer 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.
The international clinical trial, carried out at St Bartholomew's Hospital in the UK by the NIHR Barts Biomedical Research Centre, tested a one-hour operation called 'renal denervation', which uses ultrasound energy to disrupt the nerves between the kidneys and the brain that carry signals for controlling blood pressure.
Patients in the United States, France, Germany, the Netherlands, Belgium and the United Kingdom were randomised to receive either renal denervation or a 'sham procedure' - the surgical equivalent of a placebo.
Previous results from the study showed that renal denervation led to a significant and safe blood pressure lowering effect after two months in patients not taking antihypertensive medication.
In this second part of the study, the team investigated 140 patients to see if renal denervation remained effective in patients who had the option of restarting their blood pressure medication if required. They found that:
- The blood pressure lowering effect of renal denervation was maintained six months after the operation, with a greater proportion of patients treated with renal denervation (58 per cent) achieving blood pressure control compared to sham (42 per cent)
- Though the majority of patients needed the addition of medications to improve blood pressure control, more than twice as many patients were completely free of medication at 6 months in the treatment arm vs. sham arm (35.8 per cent vs 15.5 per cent).
- Renal denervation reduced blood pressure to a greater extent than sham (an 18.1 mmHg reduction in blood pressure, compared to a 15.6 mmHg reduction) at six months
- There were no safety concerns in either group throughout the six months.
UK Principal Investigator Professor Melvin Lobo from Queen Mary University of London and Barts Health NHS Trust said: "These results point towards an exciting future for this new technology. If long term safety and efficacy is proven in larger trials which are currently under way, we hope that renal denervation therapy could soon be offered as an alternative to many lifelong medications for hypertension."
The study was funded by ReCor Medical, Inc. which manufactures the Paradise® Renal Denervation System used in the study.
Notes to the editor
- Research paper: 'Six-Month Results of Treatment-Blinded Medication Titration for Hypertension Control Following Randomization to Endovascular Ultrasound Renal Denervation or a Sham Procedure in the RADIANCE-HTN SOLO Trial'. Prof. Michel Azizi, MD, PhD; Prof. Roland E. Schmieder, MD; Prof. Felix Mahfoud, MD; Prof. Michael A. Weber, MD; Joost Daemen, MD, PhD; Prof. Melvin D. Lobo, PhD, FRCP; Andrew SP Sharp, MD; Michael J. Bloch, MD; Jan Basile, MD; Yale Wang, MD; Manish Saxena, MBBS, MSc; Philipp Lurz, MD, PhD; Florian Rader, MD, MSc; Jeremy Sayer, MD, FRCP; Naomi DL Fisher, MD; David Fouassier, MD; Neil C. Barman, MD; Helen Reeve-Stoffer, PhD; Candace McClure, PhD; and Ajay J. Kirtane, MD, SM; on behalf of the RADIANCE-HTN Investigators. Circulation.
About Queen Mary University of London
At Queen Mary University of London, we believe that a diversity of ideas helps us achieve the previously unthinkable.
In 1785, Sir William Blizard established England's first medical school, The London Hospital Medical College, to improve the health of east London's inhabitants. Together with St Bartholomew's Medical College, founded by John Abernethy in 1843 to help those living in the City of London, these two historic institutions are the bedrock of Barts and The London School of Medicine and Dentistry.
Today, Barts and The London continues to uphold this commitment to pioneering medical education and research. Being firmly embedded within our east London community, and with an approach that is driven by the specific health needs of our diverse population, is what makes Barts and The London truly distinctive.
Our local community offer to us a window to the world, ensuring that our ground-breaking research in cancer, cardiovascular and inflammatory diseases, and population health not only dramatically improves the outcomes for patients in London, but also has a far-reaching global impact.
This is just one of the many ways in which Queen Mary is continuing to push the boundaries of teaching, research and clinical practice, and helping us to achieve the previously unthinkable.
About Barts Health NHS Trust
With a turnover of £1.4 billion and a workforce of around 16,000, Barts Health is the largest NHS trust in the country, and one of Britain's leading healthcare providers. The Trust's five hospitals - St Bartholomew's Hospital in the City, including the Barts Heart Centre, The Royal London Hospital in Whitechapel, Newham University Hospital in Plaistow, Whipps Cross University Hospital in Leytonstone and Mile End - deliver high quality compassionate care to the 2.5 million people of East London and beyond.
About the National Institute for Health Research
The National Institute for Health Research (NIHR) is the nation's largest funder of health and care research. The NIHR:
- Funds, supports and delivers high quality research that benefits the NHS, public health and social care
- Engages and involves patients, carers and the public in order to improve the reach, quality and impact of research
- Attracts, trains and supports the best researchers to tackle the complex health and care challenges of the future
- Invests in world-class infrastructure and a skilled delivery workforce to translate discoveries into improved treatments and services
- Partners with other public funders, charities and industry to maximise the value of research to patients and the economy
The NIHR was established in 2006 to improve the health and wealth of the nation through research, and is funded by the Department of Health and Social Care. In addition to its national role, the NIHR commissions applied health research to benefit the poorest people in low- and middle-income countries, using Official Development Assistance funding.
About ReCor Medical, Inc.
ReCor Medical is a medical device company that designs and manufactures the Paradise System, a proprietary ultrasound ablation system for renal denervation (RDN). RDN is a new potential therapeutic approach for the treatment of hypertension, one of the most prevalent medical conditions. The Paradise System is approved for sale in the EU and bears a CE mark, but is not approved for sale in the United States. The System's intravascular catheters denervate renal nerves by combining the protection of water-based cooling of the renal artery with high intensity ultrasound energy for circumferential renal nerve ablation. The Paradise System has been studied in clinical trials of approximately 300 patients to date. For additional information visit http://www.recormedical.com.