Innovations that help hearts to go with the flow

A range of new technologies and techniques is helping to keep blood flowing, writes CLAIRE O'CONNELL

THERE IS no doubt that heart disease is a major killer. But recent years have seen numerous innovations to help keep blood flowing in people who are at risk of problems.

One of the most visually impressive has been the ability to send more sophisticated instruments inside the arteries near the heart. By inserting a wire into a blood vessel at the groin or wrist, an interventional cardiologist can thread it towards the heart and use it as a guide to send in other devices such as inflatable balloons to widen narrowed stretches, tools to chip away at hardened plaque that is “furring the pipe” and implantable stents to help keep the artery open for business.

Dr Faisal Sharif, an interventional cardiologist at Galway University Hospitals, says many of the advanced treatments are now available in Ireland.

They include fractional flow reserve, which places sensors within the artery on either side of a narrowed region or “stenosis”.

“It monitors the pressure before and after the coronary stenosis so you can assess the flow,” says Sharif, who notes that it can be used for lesions where it may not be immediately clear whether a stent is needed.

Another approach, optical coherence tomography, sends a special camera into the artery that uses near-infra-red light to give a better insight into the shape and length of a plaque, and what it’s made of, he adds.

“It was essentially a research tool but now it has been adopted as a clinical tool for evaluating difficult plaques.”

The minimally invasive approach can even guide and implant an aortic heart valve in patients who cannot undergo open-heart surgery.

“The gold standard remains open-heart aortic valve replacement – the results have been fantastic,” says Sharif.

“But a procedure called transcatheter aortic valve implantation came out for patients who had been refused surgery because of other co-morbidities or increasing age.”

The procedure is not without its risks, but the medical device industry is now looking to reduce the size of the delivery system, and this could make it safer, he notes.

Another procedure exciting the innovators is not for the heart directly, but the kidneys.

Called “renal denervation”, it severs the nerve connection between brain and kidney that controls blood pressure, and it appears to work well for people who have not been responding to drug treatments for chronic high blood pressure.

“The results have been quite impressive and it has started something of a modern-day gold rush in the medical device industry – it has been compared to the invention of the stent,” says Sharif, who has been working with industry on the procedure.

He is keen to see more clinical trials of medical devices in Ireland, and he is a principal investigator in the Health Research Board-funded Clinical Research Facility in Galway. He is also a senior lecturer in regenerative medicine at NUI Galway, where he is looking at using patients’ own treated stem cells to help repair the damage caused by a heart attack.

While stem cell treatments are still in development, there have been major steps forward in tackling the symptoms of heart failure, where the heart has been damaged is finding it hard to do its job.

“Heart failure is an extraordinarily prevalent problem, there are about 100,000 people in the country with it,” says consultant cardiologist Prof Kenneth McDonald, associate clinical professor at UCD School of Medicine and Medical Science.

“But drug therapy has come on in leaps and bounds and the prognosis for patients with heart failure has probably improved by the order of 50 per cent over the last 10 years. They tend to live a much longer and a more comfortable life.”

The improvements are partly down to a better understanding of what can go wrong with hormonal systems in the body after heart damage, according to Prof McDonald, who directs the Heart Failure Unit at St Vincent’s University Hospital.

“We understand more about those types of changes now and we can introduce medicines to blunt these hormonal systems – we have very effective therapies and thankfully they can all be used in combination and are well tolerated.”

So what does the future hold? We may one day see sensors implanted into hearts that will pick up on warning signs or ‘biomarkers’ and address them on the spot, according to Prof Dermot Kenny, professor of cardiovascular biology at the Royal College of Surgeons in Ireland.

He also predicts a move towards better protective medications. “As we start to understand heart disease we are beginning to understand very early on [that] inflammation is causing the problem,” he says. “And I think what you are going to see is a lot of drugs that are used in the treatment of other diseases being used very early in the prevention of coronary artery disease.”

However, he stresses that the present arsenal of medications to reduce the risk of heart attacks works relatively well, but only if patients take them. “We have very good drugs but a significant amount of people don’t take them and that is a huge problem.”

As ever, prevention of heart disease is better than cure and simple steps like having blood pressure checked are important, according to Prof McDonald, who is national clinical lead on the HSE clinical programme on heart failure. “The onus is on us all as individuals to protect our heart,” he says.