Myopathic Cardiac Genotypes Increase Risk for Myocarditis

Visual Abstract
Highlights • AM is an important cause of cardiac dysfunction following some viral infections and has been previously linked with genetic host susceptibilities. • Sequencing data for genes related to cardiomyocyte structure and function was compared between patients with AM and sex- and ancestry-matched heart-healthy control subjects. • Putatively DVs among these genes were found in ∼16% of AM cases, contributing to viral susceptibility. • Implicated genes are ones classically associated with cardiomyopathy or neuromuscular disorders with cardiac involvement, suggesting shared mechanistic pathways. • Phenotypes, including outcomes, were similar in subjects who have AM with and without DV, therefore genetic testing will be necessary to uncover this subtype and inform risk in relatives.
Summary Impairments in certain cardiac genes confer risk for myocarditis in children. To determine the extent of this association, we performed genomic sequencing in predominantly adult patients with acute myocarditis and matched control subjects. Putatively deleterious variants in a broad set of cardiac genes were found in 19 of 117 acute myocarditis cases vs 34 of 468 control subjects (P = 0.003). Thirteen genes classically associated with cardiomyopathy or neuromuscular disorders with cardiac involvement were implicated, including >1 associated damaging variant in DYSF, DSP, and TTN. Phenotypes of subjects who have acute myocarditis with or without deleterious variants were similar, indicating that genetic testing is necessary to differentiate them.