Asymptomatic, transient complete heart block in a pediatric patient with Lyme disease.

Lyme Disease, caused by the spirochete Borrellia burgdorferi, is the most common vector-borne disease in the United States. Clinically, it primarily affects the skin, joints, nervous system, and heart. Lyme carditis occurs in 4%-10% of adults with Lyme disease. Transient variable-level atrioventricular blocks, occurring in 77% of adults with Lyme carditis, are the most common cardiac manifestation. Up to 50% of Lyme carditis patients may develop complete heart block. The incidence of Lyme carditis in the pediatric population is not well established. We present a pediatric patient with a transient asymptomatic complete heart block resulting from Lyme carditis, an under-recognized complication of Lyme disease in the pediatric population.