Every 40 seconds, a person dies from heart disease in the United States, making it the single leading cause of death in that country, as well as worldwide.
But what if all those damaged hearts could be repaired with the flick of a switch? A $1 million international study led by the University of South Australia is hoping to do just that.
The project, announced this week by the National Health and Medical Research Council, will involve UniSA Professor Janna Morrison harnessing knowledge that zebrafish, newborn mice and fetal sheep can repair their heart by activating critical molecules.
Human adults don't have the ability to do this, resulting in extensive scarring after a heart attack and poor long-term health, relying on lifelong medication or pace makers to regulate their heart.
Professor Morrison will lead a team involving researchers from Flinders University, Aarhus University in Denmark and Toronto's SickKids Research Institute, exploring whether changing the expression of a specific molecule can repair cardiac damage.
They will examine how microRNA are involved in heart regeneration. It is already known that zebrafish can completely repair damaged hearts throughout life by "spontaneous healing", switching from a mature to an immature state. Rats and mice can also regenerate injured hearts in the first few days of birth.
"It appears that humans don't have this capacity and we need to target the molecules involved in promoting this regenerative capacity," Prof Morrison says.
"Our aim is to develop a new therapeutic treatment for people who have suffered heart attacks with extensive cardiac damage.
"If we can flick the switch to repair human hearts it will have an enormous impact on improving heart health for all. Rather than seeking treatments to reduce the symptoms of heart failure, it would be possible to prevent heart damage in the first place."
According to the Heart Foundation, around 620,000 people are living with heart disease in Australia and 28 million in the United States.
Although deaths from heart disease have declined by 38 per cent in Australia, hospital admissions from heart attacks have risen sharply in recent decades, with more than 220,000 people hospitalised in 2015.