Cardiomyopathy-Associated Pathogenic Variants in Pediatric Myocarditis: A Study From the Pediatric Cardiomyopathy Registry

BACKGROUND: Studies have demonstrated that patients with myocarditis may have a higher burden of cardiomyopathy-associated genetic variants than the general population. However, data on children are limited. We compared the prevalence of rare predicted-damaging variants and clinically pathogenic variants in children with dilated cardiomyopathy (DCM) secondary to myocarditis with that in children with DCM alone and in heart-healthy controls. METHODS: Children with DCM secondary to myocarditis and children with DCM alone who underwent exome sequencing as part of a prior cross-sectional study were identified in the Pediatric Cardiomyopathy Registry, a large multicenter registry of children with cardiomyopathy. Controls from the Indiana University Biobank were matched 4:1 with myocarditis cases on genomic similarity. Rare predicted-damaging variants in cardiomyopathy-associated genes were identified using a bioinformatics approach. Clinical guidelines were used to determine clinical pathogenicity. The prevalence of variants was compared across the 3 groups. RESULTS: =1.00, respectively). CONCLUSIONS: Children with DCM secondary to myocarditis had a higher burden of variants in cardiomyopathy-associated genes than that of heart-healthy controls. Larger studies will be needed to determine the utility of routine genetic testing in this population.