Heart surgery on babies who are still in the womb, 3D plastic models of actual babies’ hearts that allow surgeons to plan their surgery, and biodegradable heart stents are among the major developments on the way for paediatric cardiology patients.
While they might sound like something from a science-fiction movie, all these developments will be discussed during a congenital cardiac study day on Thursday.
It is being held by Our Lady’s Children’s Hospital, Crumlin, to honour retired surgeon Prof Freddie Woods who revolutionised cardiothoracic surgery in Ireland.
“There have been incredible strides in paediatric cardiology over the past 40-50 years, but in the past two decades there have been immense strides, particularly with treating serious congenital abnormalities,” according to Dr Colin McMahon, a consultant paediatric cardiologist at Crumlin, who will speak about the future of the specialty during the study day.
McMahon will be covering five key future areas in his talk.
Foetal intervention
The first is foetal intervention, where the technology now exists to diagnose babies antenatally, at 18-20 weeks, with many different forms of heart defects such as hypoplastic left-heart syndrome, in which the left ventricle of the heart is severely underdeveloped.
Several centres in the US, UK and Germany are now looking at foetal intervention in these patients – that is, operating on the baby in the womb – with studies underway on foetal catheterisation, where a balloon catheter is inserted through the mother’s abdomen into the foetus’s aortic valve to see if it will help the left ventricle to grow.
“In Ireland we have a relatively small population so even if we identify patients who would benefit from that procedure, it is more likely we would refer them to a larger centre in the UK,” he says.
3D printing
Another major field of development is 3D printing of complex congenital hearts, says McMahon. This involves taking a CT scan of the patient’s heart and then using a computer programme and 3D printer to generate a plastic 3D model.
Crumlin is involved in a pilot programme on this technology and sends its data to a lab abroad, which sends back the heart model.
“I predict that in the future all children with very complex anatomy will be able to have a 3D model of their heart printed so that the surgeon can assess if they can perform a specific operation; they could, potentially, rehearse the operation on the model, and also show the parents what can be done,” he says.
Another major development in paediatric cardiology is the development of implantable ventricular assist devices, which are mechanical pumps used to support heart function and blood flow in people who have weakened hearts.
These devices help patients who need a transplant to survive outside hospital until they get a new heart: or, with some patients, they remove altogether the need for a transplant and allow them to lead a relatively normal life, which McMahon says is vital given the limited available pool of donor hearts.
Cardiac catheterisation is another area of cardiology that is seeing great developments.
Several companies are now developing stents that are biodegradable, according to McMahon.
These have specific benefits for children as the stent can do its work and degrade after three to six months, allowing the child’s heart vessel to grow without the need for multiple operations.
McMahon says the final exciting area of cardiology development is cardiovascular genetics in which, it is hoped, in the next two decades genome sequencing will help unlock the gene mutations that cause congenital heart abnormalities and treat them at the source.
While all these cutting-edge developments in paediatric cardiology are very exciting, McMahon stresses that providing the best basic care to patients remains the key focus for the specialty.
Surviving and thriving
More and more children with serious congenital abnormalities are now surviving and thriving with increased life expectancy due to the care and skill of surgeons and cardiologists, according to Dr Orla Franklin, a consultant paediatric cardiologist at Crumlin, who will also speak at the study day.
She says accurate diagnosis of babies with cardiac abnormalities in the womb as early as 20 weeks now happens in Ireland, and is a great improvement on even a decade ago.
About 30-35 babies present at Crumlin with hypoplastic left-heart syndrome annually, says Franklin. Fifteen years ago, surgery wasn’t available for most children with this condition, but now it is, and it continues to advance.
These babies can need major reconstructive surgery as early as three days old, and again at three to four months with final surgery at age three to four years.
Early diagnosis ensures these babies can be prepared for surgery as quickly as possible to allow the best outcomes. In some cases if the mother lives far away from Dublin this involves ensuring the baby is born as near as possible to Crumlin.
“This allows us to stabilise them before surgery and gives an increased chance of survival. It also maximises the protection of their other organs,” Franklin explains.
Cuts in Crumlin
Despite the harsh funding cuts Crumlin has endured in recent years, it has very good cardiac clinical outcomes and sees a huge throughput of patients, according to McMahon and Franklin.
A new cardiac unit that opened in the hospital in 2013 was paid for by external fundraising, not with HSE capital.
“There are five cardiologists in Crumlin for a population of 4.5 million people. We should have 10-12 cardiologists, so we are grossly understaffed for the population.
“We also have incredible stresses on the system and very long waiting lists given our inadequate resources, though the most critical patients receive very prompt treatments and, surprisingly, our outcomes are as good if not better than most major centres given how small our resources are,” says McMahon.
Paediatric training
He also notes that he and his colleagues have trained and conducted research in some of the best paediatric facilities abroad.
Franklin says Crumlin voluntarily benchmarks its results with the UK’s National Institute for Cardiovascular Outcomes Research (NICOR) system, with Irish outcomes “as good, if not better, than many” UK paediatric cardiology centres.
McMahon hopes the new national children’s paediatric hospital will offer Irish paediatric cardiology patients the care and facilities they deserve, and provide onsite research facilities to allow for translational bench-to-bedside research.
He also stresses the need for directly adjacent or onsite maternity services colocated with the planned hospital.
“The sickest children we see are the neonates with major congenital abnormalities, so it is vital they can be delivered as close as possible and transferred immediately,” he says.
