Probable Lyme carditis in pacemaker candidates with atrioventricular block: Preliminary results from northern Serbia

Area of Science:

• Cardiology
• Infectious Diseases
• Epidemiology

Background:

• Cardiac conduction disorders requiring pacemaker implantation are common in elderly populations.
• Lyme carditis, a manifestation of Lyme disease, can cause significant cardiac conduction abnormalities.
• The prevalence of Lyme carditis as a cause for pacemaker implantation is not well-established in endemic regions like northern Serbia.

Purpose of the Study:

• To determine the proportion of patients with new cardiac conduction disorders needing pacemakers who exhibit serological evidence of probable Lyme carditis.
• To assess the utility of serological testing for Lyme disease in patients undergoing pacemaker implantation for conduction abnormalities.

Main Methods:

• Adults with new conduction disorders requiring permanent pacing were enrolled in northern Serbia.
• Serum samples were collected at baseline and 4-week follow-up for anti-Borrelia IgG testing using a two-tier ELISA and immunoblot algorithm.
• Probable Lyme carditis was defined by seroconversion or stable/rising IgG titers.

Main Results:

• Out of 74 participants completing follow-up, 8 (10.8%) showed serological patterns consistent with probable Lyme carditis.
• Third-degree atrioventricular block was the most common conduction disorder (56.8%).
• Seropositive patients were older, and higher IgG titers were observed in men at 4 weeks; no recent tick bite or erythema migrans was reported.

Conclusions:

• About 10% of pacemaker candidates in this endemic region had probable Lyme carditis.
• Utilizing paired serology for Lyme disease in evaluating high-grade conduction disorders may enhance etiological diagnosis and guide patient management.