Lyme Carditis and High-Degree Atrioventricular Block

Canada has seen a sixfold increase in Lyme disease since being nationally notifiable in 2009. This is the first Canadian series on Lyme carditis manifested as high-degree atrioventricular block. We report 5 recent cases presented over a 2-year period. The variation of nonspecific presentations requires a high index of suspicion for prompt diagnosis and correct management. Recognizing this early would curtail the progression of conduction disorders and potentially avoid permanent pacemaker implantation.