Abstract Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) (OMIM:540000) is one of the most frequent mitochondrial maternal inheritance disorders. MELAS syndrome involves multiple organs, which generates a broad spectrum of manifestations, including stroke-like episodes, dementia, seizures, lactic acidaemia, myopathy, recurrent headaches, hearing impairment, diabetes, and short stature. The most common mutation associated with this phenotype is m.3243A>G in the MT-TL1 gene, which encodes for a mitochondrial tRNALeu (UUR). This mutation affects mitochondrial protein translation process, transduce into protein synthesis impairment and cause deficits of essential proteins for ATP production such as transport chain complex subunits leading to impairment in energy production and multi-organ dysfunction. This lack of energy proficiency could stimulate mitochondrial growth in the smooth muscle and endothelial cells, causing angiopathy and impaired blood perfusion of several tissue and organs, leading to metabolic complications and stroke-like episodes. In this case report, we present a female patient with hearing impairment as the only manifestation, who underwent an anesthetic procedure for cerebral magnetic resonance imaging, developed metabolic acidosis and hyperlactatemia, and died. Finally, the biopsy revealed a post-mortem genetic variant for MELAS syndrome.