Cardiomyopathy in children with mitochondrial disease: Prognosis and genetic background

Cardiomyopathy is a reported indicator of poor prognosis in children with mitochondrial disease. However, the association between prognosis and the genetic background of cardiomyopathy in children with mitochondrial disease has yet to be fully elucidated. Of 137 children with mitochondrial disease whose genetic diagnosis was made between 2004 and 2018, 29 had mitochondrial cardiomyopathy (21%). After a median follow-up of 35 months, the overall survival rate was significantly lower in patients with cardiomyopathy than in those without (p C (90%, died at 2 months of age) and m.3243A>G (90 and 80%, died at 12 and 13 years of age, respectively). In children with mitochondrial disease, cardiomyopathy was common (21%) and was associated with increased mortality. Genetic analysis coupled with detailed phenotyping could be useful for prognosis. •Prognosis and genetic cause of mitochondrial cardiomyopathy (CM) remains unrevealed.•Of 137 children with mitochondrial disease, 21% had CM with various genetic causes.•CM patients had lower survival rates than did non-CM patients (p