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Lyme Carditis in the Fast Lane: From Alternating Bundle Branch Block to Asystole in 12 Hours

Sara Khalil, Santosh K Padala, Chui Man Carmen Hui

    Connecticut Medicine
    |December 4, 2015
    PubMed

    Insights

    Lyme disease can cause severe heart rhythm problems, including alternating bundle branch block and asystole. Prompt antibiotic treatment and temporary pacing resolved these cardiac conduction abnormalities in a young patient.

    Area of Science:

    • Cardiology
    • Infectious Diseases
    • Electrophysiology

    Background:

    • Lyme borreliosis is a tick-borne illness known to affect multiple organ systems.
    • Cardiac manifestations of Lyme disease, such as carditis and conduction disturbances, are well-documented.
    • Infra-Hisian atrioventricular (AV) block is a serious cardiac complication.

    Observation:

    • A previously healthy 24-year-old male presented with symptoms suggestive of Lyme disease.
    • The patient exhibited alternating right- and left-bundle branch block, indicative of infra-Hisian atrioventricular (AV) block.
    • Conduction abnormalities rapidly progressed to complete heart block and asystole within 12 hours.

    Findings:

    • The case highlights a rare presentation of Lyme disease with rapidly progressing, severe infra-Hisian AV block.
    • An accelerated fascicular escape rhythm was observed during the conduction abnormalities.
    • Urgent transvenous pacing was required due to the asystole.

    Implications:

    • This case underscores the potential for Lyme disease to cause life-threatening cardiac arrhythmias.
    • Early recognition and prompt antibiotic therapy are crucial for managing Lyme carditis.
    • Complete resolution of severe conduction abnormalities with antibiotic treatment suggests a reversible inflammatory process.

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