The findings of a new study suggest that aspirin should be favoured over warfarin in order to prevent blood clotting in children who undergo surgery that re-plumbs their hearts. The research, led by the Murdoch Children’s Research Institute (MCRI) and published in The Journal of Thoracic and Cardiovascular Surgery, will have implications for clinicians when prescribing blood-thinning medications after Fontan surgery, a complex congenital heart disease operation redirecting blood flow from the lower body to the lungs. The Fontan procedure is offered to children born with severe heart defects, allowing the child to live with just one pumping heart chamber instead of two. The study involved 121 patients enrolled in the Australian and New-Zealand Fontan (ANZ) Registry. It found stroke was common regardless of which medication the patient took. But patients on warfarin had poorer bone mineral density and were at a higher risk of bleeding. She said the aspirin findings were a relief as the medication was much easier to manage and would benefit other families whose children required the procedure in the future.