Propionic acidemia (PA) is a metabolic disorder that involves a defective copy of propionyl-CoA carboxylase (PCC). It has previously been shown that there is an association between QT-prolongation in propionic acidemia. The patient seen in this case is a male in his early twenties with known PA who was found unconscious on initial presentation due to cardiac arrest with a downtime of twenty minutes. He was subsequently resuscitated and stabilized. The patient underwent placement of an automatic implantable cardioverter-defibrillator (AICD) nineteen days after the initial presentation.