Clinical trials: one man’s story of testing a device used in TAVI

Ray Jenkins from Somerset had never imagined himself as the kind of person who would take part in a clinical trial.

After open heart surgery in 2017 for aortic stenosis, which meant he needed his heart valve replacing, his focus had been on managing symptoms, following his doctor’s advice, and trying to live as normally as possible.

But when his replacement valve split in 2023 and he needed emergency surgery, he was invited to participate in the BHF-PROTECT-TAVI study.

It was a groundbreaking trial funded by British Heart Foundation (BHF) and undertaken by a team of researchers led by Professor Rajesh Kharbanda from the University of Oxford.

Ray saw this as an opportunity to contribute to medical research that could help thousands of people just like him.

“I’d never taken part in anything like this before. You hear about clinical trials, and you imagine all sorts of complicated medical procedures," the 72-year-old says.

"But when the team explained everything to me in detail, without mincing their words, it felt reassuring to know I’d be closely monitored and taken care of.”

Having already had open heart surgery, Ray saw this as an opportunity to give something back to the system that had once saved his life. 

“I found out quite a lot about my condition from being on the trial and going through the procedures, but I also felt as though I was very much involved in it,” he says.

What is aortic stenosis and TAVI?

Aortic stenosis is one of the most common heart valve conditions, affecting around 1 in 10 people over the age of 75.

The heart has 4 valves which help blood flow in the right direction through your heart.

Over time, the aortic valve – responsible for controlling blood flow out of the heart – can narrow, restricting blood flow and forcing the heart to work harder.

This is called aortic stenosis.  

Aortic stenosis is treated by replacing the damaged valve.

This can be done either by performing open heart surgery - the first procedure Ray had - or by a less invasive procedure called transcatheter aortic valve implantation (TAVI).  

During TAVI, a narrow flexible tube (called a catheter) is fed into a blood vessel in the upper leg or chest and is passed towards the heart.

The tube is used to fix a replacement valve over the top of the old narrowed aortic valve.   

TAVI has a quicker recovery time than open heart surgery, but it has some risks.

This includes a small risk of experiencing a stroke, which happens to around 2 to 3 in every 100 people having the procedure.

Watch our video guide to having a TAVI procedure:

While procedures such as TAVI and open-heart valve surgery can have a really beneficial impact, researchers are always working to refine these procedures and improve patient outcomes.

The BHF-PROTECT-TAVI clinical trial focused on finding out whether cerebral embolic protection (CEP) devices, which act as a filter to catch material that could travel to the brain and cause a stroke during a TAVI procedure, could reduce stroke risk.

It was the largest study of its kind in the world, involving more than 7,600 participants across 32 NHS hospitals. This was around 30 per cent of all NHS TAVI patients during the trial period.

The results were published in the New England Journal of Medicine in March 2025.

Ray’s TAVI clinical trial experience

When Ray became ill in 2023, doctors discovered the replacement aortic valve he’d had fitted in 2017 had spilt and he needed emergency surgery.

“I started to get very breathless just doing moderate exercise like walking my dog Betty,” Ray says.

“I was referred to the Bristol Heart Institute the following April, but I couldn’t wait that long. I was so breathless I took my wife’s GP appointment for something else and ended up being sent straight to the institute.

"It was only then I found out the replacement aortic valve had split.” 

At the hospital, Ray was told he’d need another valve replacement, and that if he chose to have a TAVI procedure, rather than undergoing open heart surgery again, he could take part in a medical trial. 

“With what I was going through, the trial felt like a way of helping others,” Ray says.

Close monitoring is an important part of clinical trials, which meant Ray had access to a deeper understanding of his procedure at every stage. 

As a result, he found himself learning more about his condition, engaging with healthcare professionals in a way he'd never done before, and feeling a renewed sense of control over his health. 

“It's strange, but being on the trial, I took an interest in my whole situation, and this meant I was somehow less scared.

"I liked the fact that they told me everything they were going to do, and they took the time to talk to me about the pros and cons," Ray says.

"I felt in safe hands.”  

Why clinical trials need patients 

Research relies on people like Ray volunteering to take part in clinical trials. Without them groundbreaking discoveries and life-saving treatments would not be possible. 

Each trial helps to build a clearer picture of how to treat and manage heart conditions.

The BHF-PROTECT-TAVI trial ultimately found that CEP devices do not significantly reduce stroke risk.

This is an important finding as it provides strong evidence that these devices should not be routinely used in the NHS.

Professor Bryan Williams, BHF’s Chief Scientific and Medical Officer, says it is a great example of the importance of BHF funding for research that answers internationally relevant clinical questions.

"This was an excellent trial. It makes it clear that the benefits of CEP devices do not outweigh the additional cost and training requirements involved. Based on this strong evidence, we would not expect these devices to be recommended for routine use in the UK.” 

In the year 2023 to 2024, there was £37million of BHF funding supporting 46 clinical trials like the one Ray took part in.  

The BHF-PROTECT-TAVI trial's conclusive result also means that researchers can now focus on other ways to prevent stroke after TAVI.

In future studies, Professor Kharbanda and his team plan to explore whether being more selective in how CEP devices are used could be beneficial.

"We need to better understand which patients are at high risk of stroke and whether embolic protection may work in those patients. This will be the basis of our ongoing research,” he says.

The research community is exploring other ways to improve TAVI outcomes too. For example, BHF-funded scientists are using advanced imaging techniques to detect heart damage caused by aortic stenosis before symptoms appear. 

With earlier detection, doctors could start treatment before damage to the heart progresses too far.

Be part of 'something bigger'

For Ray, taking part in the BHF-PROTECT-TAVI trial felt empowering.

Even though the study did not result in a dramatic breakthrough, it has contributed to a greater understanding of what makes TAVI safer for patients.

And for this he feels proud.

I'd absolutely encourage anyone who's offered the chance to be part of a clinical trial to do it.

“It’s not just about helping others, it feels like being a part of something bigger," Ray says.

“I’ve got quite a lot of living to do yet and I’m so grateful for the care I’ve received, and I’m glad to be able to give back.

“I’d absolutely encourage anyone who’s offered the chance to be part of a clinical trial to do it."

• If you'd like to find out more about taking part in a clinical trial go to our dedicated clinical trials page, or speak to your doctor.  

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