A MUM has been left "broken" after her 14-month-old daughter suffered a heart attack in a park, and was then found to have a potentially life-threatening heart condition.

Jody Crook, 33, was on a family day out in Chelmsford in August when her daughter Sienna started screaming, collapsed, and lay unresponsive on the floor. The child only survived thanks to Mrs Crook's best friend Kayleigh Charley, who performed CPR until paramedics arrived.

After being rushed to hospital, where her heartrate reached 300 beats per minute, Sienna's condition was eventually stabilised following several hours of treatment. But doctors also diagnosed her as having a heart murmur, a hole in her heart, and a irregular heartbeat.

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The family were refered to the Royal Brompton Hospital in London where Sienna was found to have Brugada syndrome, a potentially life-threatening condition where abnormal electrical activity in the heart which can cause sudden cardiac arrests.

As the condition can be inherited, the family subsequently discovered that Mrs Crook, Sienna's five-year-old brother Theo, and Sienna's maternal grandfather all also have the condition.

Mrs Crook said: “Sienna was a really happy little girl. She never had any health conditions, and even on the day of her cardiac arrest she was bright and playful.

“She’s at a very risk of having a cardiac arrests in future because she’s already had one. Little did we know that day life was never going to return to normal.

Echo: Jody with husband Jamie, daughter Sienna and son Theo Jody with husband Jamie, daughter Sienna and son Theo

“It’s been heart-breaking to be honest, it’s completely broken me. When you’ve held your child in your arms and watch them fighting for their life it does change you.”  

She added: “Nothing’s going to hold Sienna and that’s why I think she’s still here to be honest. She’s tough, she’s strong and she’s resilient.”

While Sienna has been fitted with a heart defibrillator there is no known cure for Brugada syndrome.

To help this the family are putting on a charity ball at Orsett Hall Hotel, Restaurant & Spa in October to help raise funds for The Royal Brompton Hospital which will be ring-fenced for research into the condition.

Mrs Crook added: “I just can’t sit back and accept it, Sienna could live for a year or another 50 years. I just won’t give up.”

To donate to the family's fundraiser visit the link here.