Australians should get free access to a test that shows whether their blood contains high levels of a lipoprotein that causes heart disease and has been linked to heart attacks in otherwise healthy people, leading cardiologists say.

They warn that more than 5 million Australians could have elevated levels of lipoprotein (a) – more commonly known as Lp(a) – which in higher concentrations increases someone’s risk of developing fatty plaques in their arteries.