Sudden cardiac arrest kills millions worldwide each year, including at least 12 seemingly healthy people aged 35 and under every week in the UK. In the US, about 2,000 people under 25 die annually, while in Australia, on average one person under 35 experiences sudden cardiac arrest every day, with most dying. Despite being statistically rare, it ranks among the leading causes of death for children and young adults, surpassing car accidents and various cancers. Families often have no warning until it's too late.
Personal tragedies highlight the crisis
Alexandra Thoms, a 23-year-old Melbourne woman with a double university degree and a graduate job at Deloitte, died in her sleep on 27 August 2023 from undetected arrhythmogenic cardiomyopathy. Her father, Gordon Thoms, described her as healthy, an avid skier and gymgoer. She had just moved into her own apartment and was excited about her independence. The night before her death, she assembled a flat-pack dining table with her father and sent them a picture of her dinner. She went to bed and never woke up.
Other cases include 17-year-old Edward Millear, who died after rowing training; 14-year-old Joshua Oguns, who collapsed during basketball; and 15-year-old Kent Yamazaki, who died playing tennis. The fatality rate for sudden cardiac arrest is about 90%, classified as sudden cardiac death when fatal. Over the past 50 years, cardiovascular disease deaths have dropped by 80%, but sudden cardiac death rates among young Australians have remained virtually unchanged.
Underfunded research and low awareness
André La Gerche, academic cardiologist and head of the Heart Laboratory, says research is underfunded and public awareness low. “Even professionals sort of fall back on the idea that young people don’t die very often,” he said. La Gerche chairs the Australian Sudden Cardiac Arrest Alliance. Elizabeth Paratz, cardiologist at St Vincent’s Institute of Medical Research, explains that sudden cardiac arrest involves immediate loss of consciousness and the heart stopping suddenly, requiring resuscitation.
In children, inherited arrhythmias are typical; in older teenagers and young adults, inherited structural abnormalities like cardiomyopathies are more common. About 40% of fatal cases have an “unascertained” cause, with the heart appearing normal. When a genetic cause is identified, it raises questions for family members.
The role of defibrillators and CPR
Widespread availability of automated external defibrillators (AEDs) could push survival rates from 10% to about 20%, according to cardiologists. In August 2024, 12-year-old Xavier Arruzza collapsed at soccer training in Sydney’s south-west. Bystanders performed CPR and used a club AED, delivering three shocks that revived him. His mother, Rose, said, “Without the defibrillator, I don’t think he’d… I am one of the lucky ones.”
Charities like Heartbeat of Football advocate for mandatory AEDs in public buildings, as in South Australia, and for CPR training in schools. About half of EU countries require CPR training for a driving licence. However, defibrillators cannot save everyone. “A child goes to bed and doesn’t wake up,” said La Gerche.
Genetic testing gaps
After Alexandra’s death, her family spent nearly two years identifying the genetic cause. Her younger brother Charlie, now 24, has the same advanced cardiomyopathy and now has an implanted defibrillator and takes daily medication. Gordon Thoms described the process as “long, cumbersome and stressful”. He set up Alexandra’s Mission, a charity to prevent cardiac deaths in young people, calling sudden cardiac arrest “a major, preventable public health emergency”.
Danielle Green lost her nine-month-old son Sonny to sudden cardiac death in 2021 after mild gastro symptoms. A year later, her daughter Airlie survived a cardiac arrest at five months old but died at 18 months from the same trigger. Genetic testing later revealed a rare PPA2 disorder. Green is lobbying for mandatory genetic testing in postmortems for unexplained deaths, as no Australian state mandates it. Richard Bagnall, head of the Centenary Institute’s cardiovascular research centre, says targeted postmortem genetic testing can identify at-risk relatives and enable preventive measures.
Jodie Ingles, cardiac genetic counsellor at the Garvan Institute, describes the referral system as “a total mess”, with long wait times and unequal access. Meanwhile, families continue to grieve and advocate for change. “She lived her life almost as if she knew tomorrow may never come,” Gordon Thoms said of his daughter.
