Mitochondrial trifunctional protein deficiency is a long-chain fatty acid disorder that may include manifestations of severe cardiomyopathy and arrhythmias. The pathophysiology for the severe presentation is unclear but is an indicator for worse outcomes. Triheptanoin, a synthetic medium chain triglyceride, has been reported to reverse cardiomyopathy in some individuals, but there is limited literature in severe cases. We describe a neonatal onset of severe disease whose clinical course was not improved despite mechanical support and triheptanoin.
Keywords: Cardiomyopathy; ECMO; long-chain fatty acid oxidation disorder; newborn screen; trifunctional protein deficiency; triheptanoin.