Super-size tube that means you don’t need open heart surgery

PATIENTS with blocked arteries could benefit from a new type of stent to improve blood flow. Mike Amos, 67, a retired Gatwick Airport mechanic, from Surrey, was the first person in the world to have it, as he tells DAVID HURST.

THE PATIENT

MY HEART has caused me problems since 1994, when I first suffered from chest pain and breathlessness, and angina was diagnosed. I had to have bypass surgery because one of the arteries in my heart was blocked. Over the years, I needed two more procedures to widen blocked blood vessels using stents.

My health has meant that I couldn’t play with my three grandchildren as much as I wanted to because I would get very breathless.

But apart from the fact I smoked 15 to 20 cigarettes a day, my lifestyle was reasonably healthy. I tried to exercise, ate fairly well and drank wine only if my wife Pam and I went out. And I’m not overweight (10st 7lb at 5ft 10in).

So it was a shock when, in May this year, I had a heart attack.

My memory of it is blank, but Pam heard a crash coming from the bathroom at 6.30am, where she found me unconscious and not breathing.

She alerted our neighbours and they took turns to perform CPR and get me breathing. When an ambulance arrived, I was rushed to East Surrey Hospital.

But I needed to be seen by heart specialists at a larger hospital with more equipment. Brighton’s Royal Sussex County Hospital was the first to respond to the call, and I was apparently sent to its intensive care unit.

The first thing I remember is being in the ward a week later. Doctors told me I’d had a massive heart attack, due to two of my coronary arteries becoming blocked with fatty deposits, and my heart had stopped beating.

They also revealed I had been the first person in the world to be treated with a new procedure.

ONE of my blocked arteries was the left main-stem coronary artery, which is larger than the others, and doctors had unblocked it using a special new stent that is large enough to fit snugly inside it. Standard stents are too small for this artery.

Another patient was due to be treated with this stent, but turned out to be unsuitable, and I happened to be in the right place at the right time.

Apparently, there’s only a one-in-five chance of surviving a cardiac arrest after a heart attack. If it hadn’t been for this new stent, I’d have had emergency open-heart bypass surgery, but I probably wouldn’t have survived that either.

After my operation, I felt disorientated and fuzzy, but lucky to be alive. I was then in intensive care for four days and spent a further five weeks in hospital recovering. I had cracked ribs due to the CPR and had some lung infections, probably because I was a smoker.

But I’m back at home now and, although my recovery is slow, I’m feeling a lot better — and I’ve finally stopped smoking.

I have several follow- up appointments over the next 12 weeks, but I have no doubt the extra-large stent saved my life.

THE SPECIALIST

Dr DAVID HILDICK-SMITH is a consultant cardiologist at Brighton and Sussex University Hospitals Trust. STEnTS are used to widen arteries that have narrowed due to fatty deposits building up inside them. They are like miniscaffolds, remaining in place to keep the arteries open over time, allowing sufficient blood flow to or from the heart.

Since 1996, they have improved enormously. They are now coated with a medicine that stops cell growth, so the arteries rarely re-narrow, which used to be the main problem with them. We have stents that are suitable for most situations. But for larger arteries, such as the left main-stem artery which supplies the majority of Mike Amos: Stent saved his life the heart muscle with blood, it was proving very difficult.

Despite 20 years of research, making a drug-coated stent that expands to 5.75mm (the typical width of this artery) and also fit down a 2mm tube at the wrist where it is inserted, was a challenge. The problem was an engineering one — when it’s more than 4mm in diameter (the size of most arteries), it’s a challenge to make the stent strong enough. And when the metal expands, the drug coating tends to flake off.

A stent is made up of links and hoops of metal (cobalt chromium). This mesh-like design means it can be contracted small enough to insert it via the wrist, then expanded to fit in position.

We have tried using smaller stents for larger vessels, but if an implant is the wrong size there’s a risk of clots forming around the stent. This is because the stent is not tight enough against the wall, so there’s a space where blood flow becomes sluggish.

An alternative is surgery to bypass the blocked artery, but this is a major operation. now we have a less invasive option.

Produced in the U.S., the new Onyx XL stent is nearly 20 per cent larger than existing models. It is made of the same material as earlier stents, but has more of the intricate links and hoops needed to make it strong enough. It’s coated with the drug zotarolimus, which stops the artery from re-narrowing. The extra hoops mean the drug coating is less likely to become overstretched and flake off when the stent expands.

The manufacturers came to us because I am the principal investigator for a European study on stenting in the left main- stem coronary artery. Since Mike Amos’s operation, we’ve used the stent successfully in four other patients.

Mr Amos needed intensive care afterwards because of the state of his health beforehand. But for a patient whose admission is planned — for example, if a scan has found that they have narrowed arteries — they could have the treatment one day and leave the next with nothing more than a bruised wrist.

If all goes well, this stent will soon be available in many nHS centres. By performing fewer open-heart surgeries, it could save the nHS up to £5 million.

ANY DRAWBACKS?

DR HILDICK- SMITH says: ‘ Possible complications are blockage or narrowing of the artery, which could happen if the patient’s platelets, the cells that help blood to clot, do not respond to the anti- clotting medication they are given. This would be rare, and the risk is comparable to smaller stents.

‘Three per cent of people who have their left main coronary artery treated with this new stent have a risk of heart attack or death from the procedure.’

Colin Berry, professor of cardiology and imaging at the University of Glasgow, says the stent is ‘an important step forward’.

THe procedure costs around £5,000.