Families campaigning against controversial plans to change the provision of children's heart surgery have begun a legal challenge.
A unit in Southampton is one of seven that's been chosen to stay open as part of plans to concentrate services at fewer sites.
Three centres at Leicester, London and Leeds face closure. The campaign group Save Our Surgery (SOS) is calling for a judicial review.
If it wins its action there may have to be a rethink on delivering paediatric cardiac surgery nationwide.
Taking legal action has always been our last resort option, pursued only after all other appeals to review the decision were rejected by the JCPCT.
"At the end of the day, this is about protecting the lives of children and this is why we believe that the challenges to NHS officials should be heard."
The former national clinical director for heart disease and stroke, Sir Roger Boyle, who was one of the experts advising the review, says the NHS made the right decision and that Leeds General Infirmary would continue to play a vital role providing cardiology services to children.