Patient: Ken Peters, 64, from Acton, West London had pioneering treatment
My blood pressure problem was first picked up four years ago when I was taking part in a trial for a new allergy drug to earn some extra money.
As part of the process, they took my blood pressure and found that it was slightly higher than normal.
Although it came as a surprise, it wasn’t causing any problems. I have always been fit — playing football, cricket, hockey and cycling — and wasn’t overweight (I’m 12 st 6 lb and 5 ft 10 in), so I didn’t worry.
Then, in early 2016, I signed up for another trial and, this time, my blood pressure reading had gone through the roof — normal is 140/90, whereas mine was 160/100.
They said this was dangerously high and I wasn’t accepted on the trial. They also contacted my GP to arrange an appointment.
My doctor explained that my blood pressure needed to be reduced, as pressure can damage the artery walls, which can cause blockages and lead to a stroke.
This struck a chord because my father, John, had a stroke in his late 50s. He died in his 60s from complications as a result of it.
I was prescribed amlodipine tablets — it was disappointing, as I still felt fine and hated the idea of taking regular medication.
Then, in early 2017, I read about a trial for a new treatment where they use ultrasound to burn away faulty nerves around the kidney that help control blood pressure. I called the researchers and went for a screening in March.
I wouldn’t know whether I had the active treatment or sham, but there was a chance I’d come off the medication if it went well, so I agreed to take part.
I had the 40-minute procedure in September 2017 under local anaesthetic, but remember very little. Afterwards, I felt weak, but not in pain, and had a plaster on the right side of my groin, where the incision was. My partner Angela took me home that day.
‘Since the procedure, my blood pressure has been stable and is nearly normal’, he says
The next day, I checked my blood pressure at home — it had gone down from 150/110 before the procedure to 130/90. I was thrilled. I guessed I must have had the ultrasound treatment because of the dramatic drop and this was later confirmed.
Since the procedure, my blood pressure has been stable and is nearly normal. It was a little odd not having any symptoms, yet being told I was at high risk of a stroke due to my blood pressure.
I’m no longer at risk and plan to discuss coming off the pills.
Dr Melvin Lobo is a consultant cardiovascular physician at Barts Health NHS Trust in London.
Blood pressure is the amount of pressure exerted on the walls of the arteries by blood flow.The top number in your reading (systolic pressure) is the pressure exerted when the heart contracts and forces blood around the body. The lower number (diastolic pressure) is when the heart relaxes between beats. A healthy reading is around 120/80.
When this pressure is consistently too high (more than 140/90) — known as hypertension — the heart has to work harder to pump blood, which weakens the heart muscle. The increased pressure also damages blood vessel walls, so they’re prone to rupturing or forming clots, which can cause a stroke.
Did you know? Hypertension can be caused by arteries stiffening as you age, stress, insufficient exercise and excess salt in the diet
Around 15 million people in the UK have hypertension. It can cause headaches, nausea, dizziness, blurred vision or breathlessness, but, like Ken, millions have no symptoms.
Hypertension can be caused by arteries stiffening as you age, stress, insufficient exercise and excess salt in the diet.
The initial treatment is lifestyle changes, such as diet and exercise. If these fail, then we try medication such as amlodipine, which relaxes the blood vessel walls to reduce pressure.
A small percentage of patients do not respond to drugs and many would like to come off them because it’s inconvenient or they struggle with side-effects.
For these patients, we can now offer a procedure called renal denervation, where we destroy nerves in the arteries that supply the kidneys. These nerves play a key role in regulating blood pressure — and high blood pressure can be caused by faulty signals transmitted by these nerves between the brain and kidneys. One of the aims of this treatment is that patients could stop taking drugs altogether.
Since 2012, we have used radiowaves to destroy these nerves. This has been successful, but patients need several applications (sometimes up to six blasts in one procedure), as the energy is not that efficient in hitting its target. This means there is a risk that heat from the radiowaves could damage healthy tissue.
We are now involved in trials destroying these renal nerves using ultrasound. Ultrasound uses high-frequency soundwaves and may be preferable to radiowaves, as it is more controlled and penetrates deeper into the tissue, so is more effective and fewer applications are needed.
Also, unlike the radiowave probe, the ultrasound probe has a special balloon around it, which helps cool surrounding tissue and reduce damage to healthy cells.
WHAT ARE THE RISKS?
There is a small risk of bleeding and bruising and healthy tissue could be damaged.
The nerves destroyed in this treatment may grow back, but there’s no evidence that they will send faulty messages to the brain again.
‘Based on results of recent studies, this new technique has potential in lowering blood pressure in patients with uncontrolled hypertension,’ says Andrew Webb, an honorary consultant physician at St Thomas’ Hospital in London.
‘But the studies have been relatively small and of short duration. Larger trials are needed to establish long-term safety and benefit.’
We use around two to three burns per artery with the ultrasound, compared to six with radiowaves. And, because they are less likely to cause tissue damage, we can repeat the ultrasound treatment, unlike with radiowaves. The technique is the same as the one with radiowaves.
First, we make a tiny incision in the right side of the groin and feed a guidewire through an artery, until it reaches one of the renal arteries. (There are two, one for each kidney. We treat both.)
We then pass a thin, flexible tube (a catheter) with a thin probe inside, called a transducer.
The probe is connected to an ultrasound machine controlled by the doctor. When the probe is in position on the nerves, the doctor will activate a seven-second burst of ultrasound energy. This destroys the renal nerves and stops the faulty brain signals.
It takes about 40 minutes to treat both sides. The wound is sealed with a plaster and patients can go home the same day.
The results of the randomised trial with ultrasound or sham treatment in which Ken took part were published in The Lancet in May.
They showed that in 146 patients, those who had ultrasound treatment saw their blood pressure drop by eight points or more, compared with only a slight reduction in the sham group. We plan a larger trial to monitor patients long-term.
To join the trials, please call 020 7882 5662 or email: email@example.com