A Circulation: Heart Failure study identifies a genetic variant as a likely factor that increases the risk of children with myocarditis progressing to dilated cardiomyopathy and heart failure.

Researchers describe a 'double hit' model: a child with a pathogenic cardiomyopathy mutation (first hit) contracts an infection causing myocarditis (second hit), boosting the chance of heart failure.

In the study, about one-third (34.4%) of children who developed dilated cardiomyopathy after myocarditis carried cardiomyopathy-related genetic variants, compared with 6.3% of controls, a statistically significant difference.

The work was recognized with a Top Pediatric Cardiology Research award at the American Heart Association Scientific Sessions, led by genetics researchers including Stephanie Ware, MD, Ph.D.

Led by Steven E. Lipshultz, the study used data from the Pediatric Cardiomyopathy Registry, comparing 32 children with both dilated cardiomyopathy and myocarditis to those with myocarditis alone and to healthy controls.

Findings suggest genetic testing should be considered for all children presenting with myocarditis and cardiomyopathy to identify those at higher risk for heart failure and sudden death.

The research underscores that identifying pathogenic mutations is crucial for risk assessment and timely intervention to prevent sudden death in affected children.

Children with these mutations show reduced cardiac reserve, are more susceptible to heart failure and recurrent myocarditis, and may be candidates for implantable defibrillators to mitigate risk.