Systematic review and meta-analysis of cardiac involvement in mitochondrial myopathy.

This analysis supports the presence of a more severe cardiac phenotype in MELAS and myoclonic epilepsy with ragged red fibres syndromes and with their commonly associated genetic mutations (m.3243A>G and m.8344A>G). This provides the first evidence basis on which to provide more intensive cardiac screening for patients with certain clinical syndromes and genetic mutations. However, the data are based on a small number of studies. We recommend further studies of natural history, therapeutic response, pediatric participants, and cardiac MRI as areas for future investigation.