Overall, DCMA patients frequently present early with significant cardiac issues alongside a variety of systemic issues that are all presumably related to the underlying mitochondrial dysfunction through mechanisms which remain to be completely elucidated. DCMA is a devastating disease in which many patients suffer end-stage heart failure in early childhood and which was previously fatal. In our experience, inotropes such as dopamine, dobutamine and milrinone have failed to rescue children with severe heart failure. The introduction of digoxin appears to be helpful in altering the natural course of this disease although the precise mechanism of action is not known (Greenway et al. Can J Cardiol 2018, PMID 29887217). Patients with DCMA are commonly small for gestational age and then frequently fail-to-thrive which requires caloric supplementation, nasogastric tube feeds and even surgical placement of a gastrostomy tube. Anecdotally, we have noted issues with hypoglycemia in DCMA patients when fasting or during times of stress (e.g. surgery or illness). In our experience, the provision of intravenous dextrose, as an exogenous energy supply, appears essential during these periods of fasting as suggested by the presence of hypoglycemia in some patients when support was not provided. In some patients we have noted an enlarged and fatty liver that is clinically asymptomatic and associated with mild elevations in liver enzymes and no evidence of synthetic dysfunction.