From pioneering the total cavopulmonary connection to rapid prototyping to guide treatment, Great Ormond Street Hospital has innovation at its core
Great Ormond Street Hospital (GOSH) in London provides congenital and acquired cardiac services for children from 0 to 18 years. As the biggest centre in the UK, it performs ∼800 operations a year of which 590 are open heart operations, making it one of the top five worldwide for congenital procedures.
The hospital provides highly specialized services for part or all of the UK. For cardiac care, these include heart transplants, bridge to transplant with ventricular assist devices (VADs) for children with severe heart failure, treatment for pulmonary hypertension, and complex tracheal surgery.
Great Ormond Street Hospital provided the first inpatient care for children in the UK in the 1800s. When GOSH opened its doors in 1852, it was the first hospital in the UK to provide dedicated inpatient care for children and had just 10 beds. Today, it employs 27 consultant cardiologists across a whole array of specialties, including advanced imaging, inherited cardiac disease, pulmonary hypertension, heart failure and transplantation, echocardiography, and interventional cardiology. There are 5.5 full time cardiothoracic surgeons, 40–50 junior doctors, and 8 cardiac intensive care consultants. Of the 230 nurses, 34 are advanced nurse practitioners or clinical nurse specialists. The service has 19 beds in cardiac intensive care, 24 ward beds of which 8 are high dependency, and 6 day care beds.
As divisional director, Professor Andrew Taylor manages the entirety of Cardiorespiratory Services. ‘It is relatively innovative having the whole range of services in one division,’ he says. ‘We manage the patient pathway which is crucial for interaction between teams.’
Innovation has been a core part of cardiac services at GOSH. Twenty years ago Professor Marc De Leval pioneered the total cavopulmonary connection (TCPC) which changed the way the Fontan operation was done.
De Leval was also interested in human factors, particularly for surgeons. That has led to a novel weekly review of all patients. Taylor believes that the ‘no blame meeting’ has led to improvements in clinical practice. ‘I don't think people truly know from a research perspective but it could be that the rigorous observation of what we do makes people more aware and therefore has the potential to reduce complications,’ he says.
Around 15 years ago the then professor of cardiology at GOSH, John Deanfield, focused his research on how inflammatory disease in childhood has great consequences on the cardiovascular system. The aim was to predict which children would develop coronary artery disease or vascular disease.
Over the last decade, trailblazing work has been done in percutaneous pulmonary valve implantation for children using what has become the Melody® device. Professor Philip Bonhoeffer did the initial case in Paris then came to Great Ormond Street to conduct the first clinical study in 200 patients.
A couple of years ago, the first paediatric tracheal transplant was conducted by Professor Martin Elliott.
More recently, researchers at GOSH have performed a paediatric heart failure stem cell study. Patients with dilated cardiomyopathy were injected with autologous stem cells down their coronary arteries. There were marginal improvements in left ventricular function.
Other methods of administration are being investigated that might stimulate a better response, such as putting a balloon in the coronary sinus to obstruct flow for a brief period so that the cells stay in the coronary arteries for slightly longer.
While Taylor says that ‘all stem cell work is in its infancy’, it does have the potential to help resolve one of the biggest clinical issues facing his division. Great Ormond Street Hospital has more children waiting for heart transplant than ever before. It is becoming clear that cardiac transplantation is unlikely to become the long-term method to treat these patients.
Smaller devices appear to provide an answer and GOSH has been using the Berlin Heart device, a type of VAD that sits outside the patient. But the pump and battery are sizeable and patients must stay in hospital. The next-generation HeartWare® device is implanted internally and the battery is small enough that children have gone home. However, the lifetime of the device is unknown.
‘I think if you work towards even smaller devices, even smaller batteries, and potentially stem cells that might help the heart recover a little, you might be looking at alternatives to transplantation,’ says Taylor.
Taylor is professor of cardiovascular imaging at the University College London Institute of Cardiovascular Science. His research group was the first to show that for cardiac disease, post mortem imaging can replace autopsy in children and foetuses.
Often parents want to know what has happened and why. ‘Imaging is less distressing than autopsy for parents,’ says Taylor. ‘It has been very clear that people don't want their child ‘cut open’. The information from post mortem imaging can help with planning for future pregnancies and also provide reassurance around what has caused sudden death in infancy.’
Taylor was impressed by the generosity of families when conducting the post-mortem studies. ‘I was amazed that parents would want to take part,’ he says. ‘I thought, I'm going to ask them at the worst time in their life and of course they're going to say no. But exactly the opposite happened.’
Today a big area of research at GOSH is predictive medicine using genetic information, biomarkers, imaging, and outcome data. One study in obese children the Model-Driven European Paediatric Digital Repository (MD Paedigree), aims to identify those at risk of developing vascular problems. Other studies will attempt to risk stratify patients with heart failure and patients with complex congenital heart diseases.
Percutaneous valve implantation is being taken to the next level with new and patient-specific devices for children. The procedure has progressed from one which required open heart surgery, a stay in the intensive care unit followed by the ward and time off school—to what is essentially a day care in 15–20% of children.
Also in the device arena, cardiovascular imagers at GOSH can now build a patient-specific model of the heart. They then use it to virtually implant devices—for pulmonary regurgitation, for example—and then advise the cardiologist which device is best suited to that particular patient.
On the back of that they have developed an interest in using rapid prototyping of the heart and the great vessels to plan and guide treatments like the arterial switch operations. ‘These models are really good for explaining to patients exactly what it looks like,’ says Taylor. ‘It's something they can hold in their hand and look at. What surprises me is that patients and families like the models.’
Clinicians say the models make it easy to explain what they are talking about. But research at GOSH which tested families' knowledge before and after looking at a model found that there was no change. Further studies will investigate whether taking the model home improves understanding in the long term. GOSH accepts referrals from 23 hospitals in London, the South East and East Anglia, and patients who can explain their condition to local clinicians in an emergency may be more likely to get the care they need quickly.
Advanced imaging is another area of current interest. Great Ormond Street Hospital performs ∼1000 cardiac MRIs a year. In younger patients, the scan has historically taken about an hour and in most cases it required breath holding. It meant that patients younger than 8 years needed a general anaesthetic. Great Ormond Street Hospital's work on rapid imaging, led by Dr Vivek Muthurangu, has taken one of those scans from 60 to 11 min. It obviates the general anaesthetic requirement and enables clinicians to perform three scans instead of one in the same amount of time. ‘A lot of basic science has gone into making those things happen and it has a very direct effect on patients,’ says Taylor.
Successes in ‘fixing the heart’ have turned researchers' attentions, particularly in the USA, towards the impact of operations on children's neurodevelopment. Great Ormond Street Hospital has a large National Institute for Health Research (NIHR) grant aimed at trying to understand children's needs as they grow older.
‘What is interesting is that certain children do really well after a procedure but then they hit about 13 or 14 and they're doing GCSE exams and they then find some things very difficult,’ says Taylor. ‘I think it's because suddenly they have to do a lot of things more independently in their heads, called executive function.’
It appears from cognitive development research that there are interventions that may help children at school before they start having problems. Studies are beginning to document the sorts of issues children face. Taylor says: ‘It brings you back to how you do the shortest bypass time possible, what sort of neuroprotective measures you put in place when you're doing those initial operations, and so on.’
Creating a complete pathway of care for congenital heart disease which encompasses foetal, paediatric, and adult care is also a priority at GOSH. It has a close relationship with the adult congenital heart disease service at the new Barts Heart Centre in London, with surgeons operating at both locations and advanced imaging done between the two centres. A transition clinic is held for children leaving the GOSH service in which they see a consultant and a nurse in the adult service they will attend at a different hospital.
Taylor says: ‘From a paediatric perspective, knowing what happens to your patients 20 to 30 years down the line is a very important influence on what you do to correct those new children that are coming through.’
