In the tricky business of heart transplantation, one of the biggest challenges is ensuring that a donated heart is kept in good condition for the patient whose life it will ultimately save.
Until recent years, heart transplants where the heart had already stopped beating were not believed to have good patient outcomes.
"The challenge with donation after circulatory death (DCD) is that you don't know the damage that's happened to the heart while it has stopped, so there has to be some way of assessing if this heart is actually viable for transplant,” explains Dr Yashutosh Joshi, a Cardiothoracic Registrar at St Vincent's Hospital in Sydney, Australia.
For this reason, the preference has typically been for transplants to come from brain-dead organ donors whose heart is still beating.
But over the past few years, the expanded use of devices like the Organ Care System, which keep donated hearts beating outside the body after circulatory death, are improving outcomes for patients and keeping the organs viable for longer.
Doctors in Australia also say that the use of DCD hearts has led to a significant reduction in the heart transplant waiting list in Australia.
A warm box instead of an ice box
Devices like the Organ Care System reproduce blood circulation in the heart and keep it beating outside the body.
“Instead of putting a heart in a cold esky (portable ice box) or an ice box, we're putting it in an environment where we're recirculating warm oxygenated blood into the heart,” explains Dr Joshi.
“This warm oxygenated blood allows for the heart to be reanimated. It allows the heart to beat and we can then visually assess it, we can perform some blood tests on it and then, while it's on that machine, we can sort of see if it's usable or not," he adds.
According to the Australian and New Zealand Organ Donor Registry (ANZOD), there were 112 heart transplants performed in Australia last year, but there remain between 76 to 86 people waiting for such a transplant each month.
Doctors at St Vincent's have been using the device for the last eight years and they say it's increased the number of heart transplants.
In the last two years, about a third of the hearts transplanted at the hospital came from donations after circulatory death.
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