Josh Svendsen 'was like a new baby once he was fixed” at just eight days old. He doesn't remember much of what happened, but his mum Tash does.

The 11-year-old Tauranga boy was born with a coarctation of the aorta and doctors ‘fixed' his heart.

Heartstopper challenge Ella Svendsen (front) and (L-R) her brother Josh, Rachael Wakelin, Ally Genet and Lilly Hosking will take the chilly plunge. Photo: Bruce Barnard.

'We didn't know before he was born that there was anything wrong,” says Tash. 'The condition is very difficult to pick up during scans. They knew there was something wrong because he kept getting fluid on his lungs that he couldn't get rid of.”

Eight-day-old Josh and Mum were transferred via ambulance to Starship Children's Health hospital to visit a specialist. But Josh's heart wasn't doing so well.

'They diagnosed him with the condition [coarctation of the aorta] and they ended up doing emergency surgery that afternoon,” says Tash.

Coarctation of the aorta is a congenital condition where the aorta narrows to an abnormal width.

'At one point his aorta was only the size of a pinhead for the blood to get through,” says Tash. 'There was minimal blood going to the bottom of his body.

'He had an operation where they go in from his back and they separate his ribs. They cut out the narrowed part and sewed it back together. He was like a new baby basically once he was fixed.”

Josh was just a baby when it all happened, so was his big sister Ella, 12. She doesn't remember the details, but still wants to help her little brother in any way she can.

On March 19, Ella and a few of her brave friends will be chilling out in an icy pool for five minutes to raise funds and awareness of the many children living with a heart condition and provide life-long support.

Heart Kids BOP's Bay of Plenty Heart Stopper event challenges teams of four to six to take on the chilly plunge, with the ice water reflecting its use to help slow a patient's metabolism during open heart surgery – just like what happened to Josh.

Tash says Josh has just two valve leaflets in his heart, while we have three. This is something doctors have to keep an eye on. Josh has yearly checkups, to ensure the coarctation isn't narrowing.

At age 12, he will have an MRI to get a clear picture of what's happening.

'They have said if he's going to deteriorate it may be in his adolescent years because obviously the body is changing so much that it puts that extra pressure on his heart.”

But Tash says her son is one of the lucky ones. 'In terms of his day-to-day functioning, he's pretty normal. He can play a full game of rugby, which if there was anything wrong with his heart he wouldn't be able to do.”

She says Josh just gets on with life. 'He's got a really neat nature, really caring and kind. Whether that's got anything to do with what he went through as a child, we don't know.”

Heart Kids BOP chairperson Rachael Parkes says every week in New Zealand, 12 babies are born with congenital heart defects. That's more than 600 little hearts each year needing support.

'About 450 open heart surgeries are performed on children each year – some of these are on babies in their first days of life, with a heart the size of a strawberry. Often they will need repeat surgeries and procedures as they grow.”

The Heart Stopper Challenge is at Mount Maunganui's Coronation Park on Saturday, March 19, from 10am.

Funds raised from the event will support heart children and their families in the Bay of Plenty community as well as nationwide.

For more information or to register a team, visit heartstopper.org.nz/event/heartstopperchallengebop2016 or www.facebook.com/heartstopperchallengeheartkidsbop/

To donate directly to Ella, visit heartstopperchallengebop2016.everydayhero.com/nz/teamac

DVS have teamed up with the organisers of the Bay of Plenty Heart Stopper Challenge and donated a ventilation system worth $3,600 to raise funds for Heart Kids.

The DVS ventilation system is being auctioned on TradeMe with no reserve and a starting price of just $1,800. All proceeds from the auction will go to Heart Kids Bay of Plenty. View the TradeMe link here.