Australian cardiologists are calling for wider genetic testing at specialised heart centres for survivors of idiopathic sudden cardiac arrest, saying it might reveal cases of ‘concealed cardiomyopathy’.

In their study of 36 people (mean age 37 years) who survived a sudden cardiac arrest and for whom no underlying cause had been found, eight patients (22%) were found to have a genetic anomaly after broad phenotypic genetic testing.

All patients had attended the genetic heart disease multi-disciplinary clinic at Sydney’s Royal Prince Alfred Hospital between 1997 and 2019 and testing had been carried out for genes associated with channelopathies and cardiomyopathies.

“Interestingly, seven (88%) disease-causing variants identified were in cardiomyopathy genes despite the absence of diagnostic structural changes on imaging, the authors wrote in the International Journal of Cardiology.