A pioneering generation: people with complex congenital heart disease living longer

People born with half a heart or single-ventricle congenital heart disease (Fontan-CHD) are now living longer than ever before, thanks to advances in medicine and technology.

Scientists from the Heart Research Institute (HRI) say it’s resulted in an unprecedented wave of survivors with poorly characterised and complex health problems.

Associate Professor Rachael Cordina is about to embark on a first longitudinal study of its kind anywhere in the world, to understand the potential mechanisms, timing and trajectory of neurocognitive dysfunction within this growing population.

“There are ranging degrees of wellness with people living with the condition, many of whom are now expected to now live well into their 60s,” says Assoc Prof Cordina, who conducts her research within HRI's Clinical Research Group.

“Although many people living with a Fontan circulation are very highly functioning, we know that there is an increased risk for learning difficulties and lower brain volume – but we don’t really understand why because this is a pioneering generation. This operation was only first developed in the 1970s to help kids survive.”

Fontan surgery connects the systemic veins to the pulmonary arteries so that the venous blood with low oxygen returning from the body completely bypasses the heart. This creates a very unusual circulatory system that might affect organ function.

“Although many people are doing really well, our research has already shown that young people living with Fontan-CHD have increased rates of neurological injury and neurocognitive impairment compared with less complex CHD. This may impact their social functioning and quality of life,” Assoc Prof Cordina says.

A lack of knowledge of the underlying reasons for these neurological complications is preventing doctors from being able to appropriately target areas in need of intervention, meaning more unnecessary appointments and increasing the economic burden on both the patient, their family and the healthcare system.

Neurodevelopmental disability is well-recognised in children with complex CHD. However, research has rarely extended beyond childhood – until now.

“We have the opportunity to re-study our previously reported cohort more than five years later,” she says.

The research, which is supported by funding through the NSW Cardiovascular Research Capacity Program, will be the first longitudinal follow-up study of neurocognitive function and brain morphometry in the setting of complex CHD.

“Our follow-up study will build on our earlier findings to help us understand the potential mechanisms, timing and trajectory of neurocognitive dysfunction within this growing population.

“This group represents one of the costliest paediatric health conditions and is rapidly expanding, due to improved surgical and critical care – this has resulted in an unprecedented wave of survivors with poorly characterised and complex health problems.

“For decades it was all about keeping them alive as children, but advances in medicine have meant we now have a large cohort of patients who have reached adulthood,” Assoc Prof Cordina continues.

“The patients and families are just so grateful to have someone who understands that journey, to be involved with their care. I’m helping a new generation of people, whose parents were told they’d never survive – watching them graduate, get married and have families of their own.”