Radio-wave treatment reduces effects of high blood pressure

A new device that uses radio waves to reduce high blood pressure has been successfully trialled in London and Glasgow.

The technique, pioneered by researchers in Australia, involves transmitting radio-frequency energy via a catheter to disable overactive nerves in the kidney that are involved in regulating blood pressure.

Although the treatment didn’t eliminate the patients’ high blood pressure, it did reduce the risk of strokes and heart attacks, and could be particularly useful in cases where drugs have been ineffective.

‘It is the most exciting development in this field for many years,’ said Prof Alan Jardine from Glasgow University’s Institute of Cardiovascular and Medical Sciences − one of the 24 international sites that were involved in the study.

‘Before being involved in the trial, the patient I treated was on eight different forms of medication for her high blood pressure. Now she is on none at all and has been free of medication for two months.’

The study, published in the medical journal The Lancet, showed that the average systolic blood pressure of the 49 patients who completed the treatment was reduced by 32mmHg to 146mmHg.

After six months, 84 per cent of these patients had seen a reduction in systolic blood pressure of 10mmHg or more, compared with 35 per cent of the control group.

The procedure, which is similar to that used to widen blood vessels, uses a catheter that is inserted into the upper thigh and then fed up to the renal artery at the kidney. The renal nerves are then silenced using radio-frequency energy.

The catheter device – known as the Symplicity Catheter System – was produced by US medical technology firm Ardian, which also funded the study.

The worldwide research was led by Prof Murray Esler, associate director of the Baker IDI Heart and Diabetes Institute of Melbourne, Australia.

He said: ‘Combined with findings from an earlier study, which demonstrated the safety and durability of the therapy, these results fuel our enthusiasm for the potential of this treatment to significantly impact the standard of care for the large number of patients suffering from this disease.’

Though it has no symptoms, high blood pressure is the number one risk factor for premature death worldwide − affecting about one in three adults.

Nearly half of Europeans suffer from hypertension and, in the US, approximately 75 million people are affected − only two thirds of whom are treated.

Of those receiving treatment, approximately half are not achieving target blood-pressure levels. The medications often prescribed for hypertension must be taken daily for the duration of a patient’s life, can be costly and often result in side effects that can negatively impact quality of life.

Globally, the estimated annual healthcare expenditure directly related to hypertension is approximately £310bn.