CSIRO 3D prints complex heart stents

Researchers from CSIRO have made it possible to 3D print tailor-made aortic stents, an implantable biomedical device used to treat narrow or blocked arteries.

The development in partnership with Wollongong-based Medical Innovation Hub is a paradigm shift in the production of self-expanding metallic nitinol stents for Peripheral Arterial Disease (PAD), which afflicts more than 10 per cent of Australians.

PAD is a condition in which fatty deposits collect and reduce blood flow in arteries outside the heart — most commonly in the legs.

CSIRO Principal Research Scientist Dr Sri Lathabai said the selective laser melting process allowed them to create complex products with high geometric accuracy that are patient specific.

Dr Lathabai said: “Nitinol is a shape-memory alloy with superelastic properties.

“It is a tricky alloy to work with in 3D printing conditions, due to its sensitivity to stress and heat.

“We had to select the right 3D-printing parameters to get the ultra-fine mesh structure needed for an endovascular stent, as well as carefully manage heat treatments so the finished product can expand as needed, once inside the body.”

Most stents used in operations are off the shelf, with Cook Medical in Queensland the world’s only supplier of bespoke stents, sewn to order to match a patient’s particular heart condition.

However this is a highly skilled manual process, performed by staff mostly formally employed in the textile, clothing and footwear sector.

Cook does not appear to be involved in the new work – a new company, Flex Memory Ventures, has been established to drive commercialisation of the technology.

CSIRO said the ability to 3D print stents is expected to improve sizing options, preserve essential anatomy, and enable diameters and shapes to suit individual patient requirements.

Mass production could be possible, reducing costs.

The process could also allow for individual stents to be made on-site, under the surgeon’s direction, reducing inventory and saving money.

Picture: CSIRO/ five sizes, proof-of-concept stents

Subscribe to our free @AuManufacturing newsletter here.