Predicting sudden cardiac death risk in children

GOSH researchers have developed the first ever tool to identify children at risk of sudden death from a rare heart condition called hypertrophic cardiomyopathy (HCM).Children identified at high risk have the option of being fitted with an implantable cardioverter defibrillator (ICD) - a small device that can shock the heart back into a normal rhythm if they experience a life-threatening abnormal heart rhythm and could potentially save their lives.

HCM is an inherited heart condition that causes the heart muscle to become thicker and makes it harder for the heart to pump blood around the body. It is thought to affect 3 in every 100,000 children but most people with HCM have few, if any, symptoms so experts think that the incidence may be much higher.

HCM can lead to life-threatening abnormal heart rhythms and sudden heart attacks, which is the main cause of death in children with the condition. Although there are tools which can help predict the risk of sudden death in adults with the condition, until now they haven’t existed for children.

The researchers, who were based at GOSH and the UCL Institute of Cardiovascular Disease, studied over 1000 anonymised medical records from cardiac centres around the world to find out what factors are associated with a higher risk of sudden death in children with HCM.

They looked at data from heart ultrasound scans (ECHO) and ECGs, which record the electrical activity of the heart, as well as informationon the patient's symptoms like unexplained fainting and whether the child had had abnormal heart rhythms in the past.

Led by consultant paediatric cardiologist at GOSH Dr Juan Kaski, the team used the medical information to develop a prediction tool called 'HCM-Risk-Kids - the first method to identify the risk of cardiac death in children with HCM. It uses a different set of risk factors to the adult prediction tool. Dr Kaski is also Honorary Senior Lecturer at the UCL Institute of Cardiovascular Science.

The tool provides an individual risk for each patient so for patients at high risk, it gives families the option to be fitted with a device which could save their child's live. It also helps reassure families of those children with HCM who the tool identifies as unlikely to experience a cardiac arrest.

The research project was funded by the British Heart Foundation and underpinned by the support of the National Institute for Health Research (NIHR) GOSH Biomedical Research Centre. The project also received funding from Max's Foundation through GOSH Charity.

12-year-old Kulthumi lives in Greater Manchester with her aunt Tunde and uncle Abi. She was diagnosed with a rare heart condition called cardiomyopathy when she was a baby. Heart problems are very common in Kulthumi’s family with several family members sadly passing away from similar conditions all in a very short space of time.

Kulthumi was one of over 1000 patients to be included in the research. Data from her medical records and heart tests like ECHO and ECG, was analysed alongside lots of other patients and used to develop the prediction tool.

Several years ago Kulthumi came to Great Ormond Street Hospital to have an implantable cardioverter-defibrillator device (or ICD) fitted under her skin. It constantly monitors her heart rate and helps correct any abnormal heart rhythms.

Her Aunt Tunde explains, “The device is there to help monitor how she is doing. It helps reassure her and kicks in if there are any problems. We come to GOSH every month and the data on her heart rhythms is downloaded. Sometimes if they see a spike of activity the team ask what she has been doing and then we have to try to remember!”

Kulthumi, has a gift for languages. Tunde says, “For the last few years of primary school Kulthumi went to school in Spain. After only three weeks the headteacher told me she had never seen anyone pick up the language so quickly. Now Kulthumi is fluent.”

Kulthumi is now at secondary school where she has extra support because of her condition. “Her schools have always been very supportive. They make sure she doesn’t have to carry any books between lessons. Kulthumi gets breathless if she has to rush so she is allowed to leave classes a bit early to get to the next one on time.”

At home, Kulthumi also enjoys cooking and baking and loves playing the piano by ear. “She is anything but subdued even though she has had a very tough time, says Tunde. “She tends to just get on with things and has a great disposition. Her outlook makes me – as an adult – feel very inspired and think why should I worry about anything.”

Tunde adds, "Inherited cardiac conditions like this have a big effect on the whole family. They can cause anxiety and mental health problems as it’s such a lot to deal with. Heart problems like this are found all over the world including in the African population but it’s something that people don’t talk about very much.

"Kulthumi really wants to raise awareness of her condition. She wants people to know its ok to talk about it and ask questions rather than assuming. We'd like to thank all the professionals who have helped care for Kulthumi as well as all our friends and family for their support".

Pictured above L-R: Research nurse Ella Field, senior researcher Dr Juan Kaski, Kulthumi, lead researcher Dr Gabrielle Norrish.