Title : Atrioventricular block in lyme carditis successfully treated by oral doxycycline
Abstract:
Introduction:
Lyme carditis has been reported in 1 to 5% of diagnosed patients with Lyme disease. The most common presentation of Lyme carditis is conduction system disturbances such as atrioventricular (AV) block.
Case Summary:
We report the case of a 35-year-old male without significant past medical history presented with two weeks of worsening fatigue, dizziness during strenuous efforts and migratory arthralgia after spending one week in Fontainebleau forest (France) one mounth ago. Serial EKGs showed Wenckebach heart block and intermittent nodal 2/1 AV block confirmed by electrophysiological exploration. An exercise stress showed improvement of nodal conduction in effort and third degree (AV) block with high junctional escape rhythm on recovery phase. Serology showed positive Lyme titers for both IgM and IgG. After consultation with Infectious Disease, we opted for 3 weeks of oral doxycycline. After the treatment course had been completed the patient’s heart block and other symptoms had resolved on follow-up including long-term Holter Rhythm Monitoring.
Conclusion:
Lyme carditis is an important reversible cause of heart block, especially in endemic areas. Prompt recognition of this potentially lethal condition, with appropriate initiation of antibiotics, can improve clinical outcomes and avoid unnecessary pacemaker implantation.
