The findings in a patient with complete AV block and intra-atrial conduction disturbances due to
Lyme disease are presented. The electrocardiographic follow-up and serial EP findings suggest that complete AV block in
Lyme disease may signify a more extensive affection of the AV conduction system (with eventually attendant intra-atrial conduction disturbances) than described in earlier reports. An almost complete resolution of the considerable damage to the conduction system occurred within two weeks.