Introduction: Propionic acidemia (PA) is a rare autosomal recessive metabolic disorder, which is rarely associated with cardiomyopathy. Since the serious metabolic decompensation, acidosis, ketonuria, and hyperammonemia, are triggered by catabolic stress such as infection, surgery, or inadequate nutrition, nutritional management is important and contributes to treatment.
We report a case with PA related cardiomyopathy who required special nutritional management to prevent metabolic decompensation at implantation and removal of left ventricular assist device (LVAD) and heart transplantation (HTx).
Case: A 19-year-old previously healthy man experienced the first episode of heart failure at 16 years of age. He underwent LVAD (Jarvik2000) implantation as bridge to transplantation at 18. He had recurrent LVAD driveline infections and subsequent sepsis triggering acidosis and hyperammonemia 1.5 years after implantation. He was diagnosed with late onset PA and special nutritional management for PA was started.
He underwent LVAD removal due to pump infection 2 months later and required inotropes until he underwent HTx at 19 years of age.
Nutritional management after LVAD removal and heart transplant, were carefully performed based on the previous experience. To prevent metabolic decompensation triggered by surgical catabolic stress, vitamin cocktail (Vitamin B1, B2, B12, C, and Ubidecarenone), biotin, L-carnitine, and parenteral nutrition consisting of glucose and amino acid were given immediately after surgery. Elevation of blood lactate and ammonia early post-op were resolved by higher glucose intake and lower protein intake and mechanical ventilation was discontinued 5 days after LVAD removal. Therefore, intravenous high dose glucose administration was started the day before HTx and no increase in blood ammonia was observed and he was exutubated 1 days after HTx. After starting oral intake, protein restricted diet and special milk formula for PA without isoleucine, valine, methionine, or threonine were gradually increased. Glucose infusion was continued until he had adequate dietary intake. Medium chain triglyceride (MCT)-oil administration waited for improved ketoacidosis to avoid ketone synthesis. Although lactate slightly increased for several days after surgery, the postoperative course was uneventful.
Discussion: In patients with PA related cardiomyopathy, meticulous nutritional management based on pathophysiology of PA is useful to prevent metabolic crisis at major surgery, such as LVAD implantation and HTx.