Third-degree heart block secondary to Lyme carditis

Third-degree heart block is an uncommon but severe and potentially fatal complication of Lyme disease. We present the case of a previously healthy 42-year-old male with no prior cardiac history who developed persistent third-degree heart block and Bell palsy secondary to untreated Lyme disease. The patient later achieved complete symptomatic resolution with antibiotic therapy and avoided intervention via cardiac pacing. This case highlights a need for increased awareness of the clinical manifestations of Lyme disease and disseminated Lyme disease to improve patient outcomes and reduce potential complications.