Q; 34 year old man with recent Lyme disease is getting transferred to ICU for trans-venous pacemaker. EKG shows only 1st degree heart block. What could be the reason?


Answer:  Patients with lyme disease and first degree AV block with a PR interval more than or equal to 300 msec, should be watched in controlled environment and should be considered for a temporary pacemaker. Treatment with antibiotics should be pursued. Actually, improvement in PR interval could be a guide to a response to antibiotics in lyme disease carditis.



Reference: 

Wormser GP, Dattwyler RJ, Shapiro ED, et al. The clinical assessment, treatment, and prevention of lyme disease, human granulocytic anaplasmosis, and babesiosis: clinical practice guidelines by the Infectious Diseases Society of America. Clin Infect Dis 2006; 43:1089.