Lyme is a tick-borne disease. The genetic diversity of Borreliae its distribution worldwide and its epidemiology have been related to different clinical manifestations. Carditis is a rare manifestation of Lyme disease. The commonest abnormality is atrioventricular block of various degrees, though other rhythm abnormalities have been reported. Pericarditis, myocarditis, cardiomyopathy and degenerative valvular disease have been associated with B. burgdorferi. Temporary pacing might be required in unstable patients. The majority of the conduction disturbances have a benign prognosis, if the infectious agent is identified and treated appropriately.