We report the case of a 27-year-old woman with a history of Kearns-Sayre syndrome and a double mitral lesion who underwent surgery without complications. Anesthetic induction was achieved with propofol and fentanyl, and maintenance was with nitrous oxide and oxygen through a face mask. There were no instances of O2 desaturation or hemodynamic alterations. The postoperative period transpired without adverse events and the patient was released 24 h after surgery. The management of anesthesia in this rare mitochondrial disease is described, and anesthetic alternatives are discussed as depending on clinical findings that can occur in the context of these syndromes.