Research

Repairing hearts born with congenital heart disease

Professor Massimo Caputo repairs the hearts of children born with congenital heart disease. He tells Sarah Brealey how BHF support is helping him improve lives.

Professor Massimo Caputo

Stitching together tiny hearts is what Massimo Caputo does best. He reshapes hearts that have not quite formed the way they should, correcting errors that sometimes arise as the embryo develops. Holes where no holes should be, malformed heart valves, blood vessels that are too narrow or connect to the wrong place – all these, and more, are things that Professor Caputo puts right.

But being a brilliant surgeon goes beyond surgery. He’s also a researcher whose excellence has been recognised with the title of BHF Professor of Congenital Heart Surgery at the University of Bristol. The BHF has funded him £1m over five years, allowing him to pursue several areas of research.

Professor Caputo reshapes hearts that have not quite formed the way they should, correcting errors that sometimes arise as the embryo develops

One of his research priorities is using stem cells to avoid the repeated operations many young people with congenital heart disease endure. This is because replacement heart valves or patches inserted during surgery as young children cannot grow with their hearts and gradually break down.

Professor Caputo explains: “We are trying to create living tissue, whether it’s a valve or a blood vessel or a patch, that will grow with the child, and that does not deteriorate. I think that would massively change their quality of life.

“Every time you do heart surgery on the same person it gets more risky. Even though we are now getting good outcomes in terms of survival, there is still the risk of complications – infections, damage to the brain or lungs – that can affect quality of life long term. And there is the psychological toll of repeated surgery, too.”

Professor Caputo hopes the blood vessels made from stem cells will be ready in years rather than decades. The first tests in patients could start within three years, although it’s likely to take five to 10 years to prove they’re safe and effective.

Making heart surgery better

Another area of Professor Caputo’s research is carrying out clinical trials to find the best ways to do heart surgery. His first research grant, in 2003, came from the BHF. Back then, he wanted to know whether cooling the body during cardiac surgery, known as therapeutic hypothermia, leads to better results. The question is still relevant today.

We have now shown that for medium-risk children it is unnecessary to cool the body, and for some organs it could even be harmful

The principle is that cooling the body means the organs don’t need as much oxygen, which is thought to be a good thing during heart surgery. But lowering and raising body temperature can also have damaging effects. “Our pilot study led to more clinical studies,” says Professor Caputo. “We have now shown that for medium-risk children it is unnecessary to cool the body, and for some organs it could even be harmful. The next step is to find out if this is true for high-risk newborns and infants. The funding as part of my BHF chair award is helping us to do this.”

There are many other areas where his BHF-funded research has led to changes that help patients. Cardioplegia is a chemical mixture used in heart surgery to stop the heart beating, so surgeons can operate more easily. BHF research has helped surgeons choose the best type of cardioplegia. “We now know that it is better to use blood cardioplegia [where chemicals are mixed with the patient’s own blood],” says Professor Caputo.

"We also did a study looking at 'blue babies' [who are suffering from low oxygen levels] during heart surgery, and found that giving them high oxygen levels in this type of surgery can actually damage the heart and brain. Before this, we had been giving high oxygen levels to these patients, so it was important to discover this."

To do research like this successfully, you need numbers – the larger the numbers of patients, the more reliable the findings are likely to be. That’s why one of Professor Caputo’s ambitions as BHF professor is to set up a network of research centres that will share their findings. 

Massimo Caputo and his team performing heart surgery

Massimo Caputo and his team performing heart surgery

Overcoming personal challenges

One of the challenges of someone in Professor Caputo’s position is dividing his time between research and surgery. “With children’s surgery you don’t just operate, you are very involved,” he says. “You follow them into intensive care, you go and see them every day and talk to the parents, so it can take up a lot of time. But you just have to find a way of dealing with that and also carrying out research.

The most complex operations can last four hours or more, although during the crucial part, when the heart is stopped, it’s essential to work as quickly as possible. It can be an emotional and physical challenge. “[But] after you finish an operation and everything has gone well, it’s a great feeling,” he says.

Professor Caputo likes to hear news from his former patients. “Often as a surgeon you don’t see them again – their cardiologist follows them up,” he says. “So when I get sent photos of them growing up it is a really nice feeling. I have been sent pictures of someone climbing a mountain and snowboarding, and that was wonderful.”

With children’s surgery you don’t just operate, you are very involved. You follow them into intensive care, you go and see them every day and talk to the parents

The hardest thing is the small number of occasions when things don’t go well. “When you lose a child around the operation time, it is a terrible moment,” he says. “I tend to disappear, sit quietly, get out of it for 24 hours, and not speak to anybody. It affects you for a good week or two. Then you start operating on the next patient, and you have to move on.”

Fortunately, deaths are the exception, and the vast majority of children with congenital heart disease now survive thanks to surgical advances that the BHF has helped to pioneer. This means there are more adults with congenital heart disease than ever, creating new challenges for Professor Caputo and his colleagues.

“Some have surgery once or twice in adulthood and go on to lead a normal life with no limits. But we also have issues relating to complex re-do operations in
young adults,” says Professor Caputo. “This is a challenging group of patients to care for because they are active and often want to have a family. There are lots of issues with pregnancy and congenital heart disease – for some congenital conditions, unfortunately, the advice is not to become pregnant.

“We hope the research we are doing will help the whole population with congenital heart disease. We are also looking at new, less invasive types of surgery, such as pulmonary valve replacement where we make a smaller incision and don’t have to stop the heart.”

Professor Massimo Caputo

Following heart surgery pioneers

Professor Caputo first came to Bristol in 2004, “because of Professor Gianni Angelini, who is well known in the BHF and around the world.” Professor Angelini is BHF Chair of Cardiac Surgery at the Bristol Heart Institute. “He has been almost like a father for me in terms of helping me progress in my career and developing me as an academic,” says Professor Caputo. “He is one of the major academics in the world of cardiac surgery.”

Every cardiac surgeon wants to be a BHF chair. To have achieved this and to be part of this BHF family is a peak of my career

Now Professor Caputo also holds a prestigious BHF chair position. “One difference the BHF chair has made is that people come to you,” he says. “It is difficult to get colleagues involved in trials in congenital heart disease, but just to have this title has changed things.

“Every cardiac surgeon wants to be a BHF chair. To have achieved this and to be part of this BHF family is a peak of my career. For me, it’s the fact that I am following in the footsteps of people like [former BHF professor] Sir Magdi Yacoub and Gianni Angelini. You try to emulate people like that, and that drives you.

"I genuinely believe that surgeons can do more research, helped by organisations such as the BHF, and I think the BHF is keen to help achieve that.

"I believe that the best is yet to come.”

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