Abstract
BACKGROUND: Infantile-onset Pompe disease (IOPD) is a lethal disorder, but enzyme replacement therapy (ERT) has dramatically improved the prognosis of these patients. CASE SUMMARY: An 18-year-old male patient, who had been diagnosed with IOPD based on decreased α-glucosidase activity in his infancy and received ERT, visited an emergency department at Kyoto University Hospital with poor complexion. An electrocardiogram showed extreme bradycardia and complete atrioventricular block (cAVB), and permanent pacemaker was implanted for cAVB. DISCUSSION: ERT has reduced the risk of death in patients with IOPD; on the other hand, severe cAVB in those patients needs to be recognized as a rare complication. TAKE-HOME MESSAGE: cAVB is a rare but critical complication in long-term survivors of IOPD and deserves attention.