Tiny plug that stops a dicky heartbeat triggering a stroke

HALF a million Britons have atrial fibrillation, a faulty heartbeat which increases the risk of stroke. Ann Read, 72, a retired carer from Littlehampton, West Sussex, was given a new implant to prevent this, as she tells CAROL DAVIS . . .

OTHE PATIENT

N MOTHER’S Day last year, I was at a restaurant with my four children when I had a frightening collapse. Getting up from my chair, black spots suddenly appeared before my eyes and I lost consciousness.

I came to moments later and soon felt better. But later that night I collapsed again, this time facedown on my bathroom floor.

I remember waking up and seeing my daughter, and the next thing I knew I was being taken by ambulance to Worthing Hospital.

The doctors told me I’d had a stroke, caused by bleeding on the brain. I was shocked, as there had been no warning sign.

However, it may have been linked to the fact that I was taking warfarin to thin my blood.

Ten years earlier I had been diagnosed with atrial fibrillation, a type of irregular heartbeat which can cause clots to form in your heart. If these travel to the brain, they can cause a stroke, so I was prescribed warfarin.

I took it for years with no apparent side-effects. But after my stroke I came off it immediately, as it seems to have led to a different type of stroke — from a haemorrhage in my brain.

Immediately after the stroke I couldn’t move the right side of my body, but following several months of physiotherapy my arm became fully mobile again (though my right foot still drags on the floor).

But without warfarin I was no longer protected from blood clots, so I was terrified I might have another stroke and gave up driving.

Indeed, in October last year, I did have another stroke — this time caused by a blood clot in the brain — while I was visiting a friend. Luckily, there were no lasting effects.

But my doctor referred me to Dr David Hildick-Smith, a consultant cardiologist at the Sussex Cardiac Centre, to discuss other options.

He explained that he was trialling a new device to stop blood clots forming without the need for warfarin. Apparently, there is a pocket in the heart which can trap blood, so clots often form there. This was probably what happened in my case.

Dr Hildick-Smith was using a mesh device, known as Amulet, that could be placed over this pocket to stop clots travelling round the body. And the operation would be minimally invasive — they would just thread the device up through a vein in my leg.

I had the hour-long procedure two weeks later under general anaesthetic. I went home the next day feeling fine, though I had ice packs on my leg to ease the swelling. I know the device is protecting me against stroke, and I feel so much more confident now: I can do things such as go on holiday without worrying.

THE SPECIALIST

DAVID HILDICK-SMITH is a consultant cardiologist at Brighton and Sussex University Hospitals NHS trust. AROUND half a million Britons have atrial fibrillation, when the upper chambers of the heart — the atria — contract rapidly and irregularly, due to faulty electrical signals.

This means blood is not pumped through the heart effectively. Instead, it can pool in a pouch in the left atrium called the left atrial appendage.

This blood can form clots, which can then pass to the brain: patients with atrial fibrillation have five times the normal risk of stroke, and 90 per cent of clots related to this form in this pouch. One way to stop the irregular heartbeat is to shock the heart back into normal rhythm, or burn heart tissue to stop the abnormal signals being transmitted. But in most patients atrial fibrillation will persist.

In this case, we can offer warfarin or newer types of anti-coagulant drugs to thin the blood, so clots are less likely to form.

However, warfarin can increase the risk of a haemorrhage. If a blood vessel in the brain starts bleeding, which is known as a haemorrhagic stroke, it can damage brain tissue. There is a 1-2 per cent risk that people on warfarin will have a major bleed.

Amulet, a device developed in the u.S. in 2007, gives us another option. It is made of a mesh of nitinol (an alloy of nickel and titanium), and shaped like a ring with a lid on it — a bit like a tiny straw hat.

It effectively closes off the appendage. If clots do form, they stay in the appendage, which will eventually become sealed as clots stick to the fibrous mesh. There are other devices that close off the left atrial appendage, such as the Watchman, which looks like a mesh jellyfish.

But one advantage of the Amulet is that cardiologists are already used to using disc-shaped implants to close holes in the heart, so they are used to the technology. And Amulet comes in eight sizes, from 16 to 34mm (the Watchman comes in five sizes).

The left atrial appendage varies in size and shape, but now we can close pretty much any opening. There is no major operation, we simply compress the Amulet and pass it through a vein to the heart. Once there, it will go back to its original shape.

First, with the patient under a general anaesthetic, we put an ultrasound probe down their throat to check there are no clots in the atrium (which could become dislodged and cause a stroke). We also use X-ray guidance to help us place the device accurately.

Then I make a 2-3mm incision in the thigh and feed in a long tube with a needle at the end, up to the heart, to puncture the septum, the wall of tissue that divides the left and right atria.

using another tube, I then feed the Amulet into position through the puncture wound to the left atrial appendage. I choose a size slightly larger than the appendage so it will fit snugly. It is held in place by tiny hooks on the outer rim of the Amulet.

The puncture wound is so small that it will close naturally.

Skin will grow over the lid so the left atrial appendage will be closed off for ever (which seems to cause no ill-effects), and the device will never need to be replaced.

Patients usually go home that day, and after six months no longer need anticoagulants because the pocket in the heart will have closed completely.

A new study presented at the Transcatheter Cardiovascular Therapeutics conference in October showed that closing the left atrial appendage with this kind of device significantly reduces stroke risk and prolongs life in atrial fibrillation patients.

This technique is offered at ten NHS centres, but I’d like to see it offered more widely to patients who can’t tolerate warfarin.

ANY DRAWBACKS?

‘THIS procedure is relatively lowrisk but we have to warn patients that it carries about a one-in-a-thousand risk of complications, such as puncturing the wall of the heart instead of the septum and causing bleeding,’ says Dr Leonard Shapiro, a consultant interventional cardiologist at Papworth Hospital in Cambridge.

‘And there is a theoretical risk of trapping air in the device, which could potentially block a blood vessel around the heart and cause a heart attack. But we flush the device out with saline repeatedly before using it to prevent this.

‘Overall, this is a very good procedure and I would like to see the NHS fund it more widely.’

THE procedure costs the NHS £7,000 to £8,000. Privately. it costs

£10,000 to £15,000.