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[High-degree atrioventricular (AV) block]
Peter Hammarlund1, Erik Ljungström2, Daniel Bremell3
1Specialistläkare, kardiologsektionen, Helsingborgs lasarett.
Insights
High-degree atrioventricular block in younger patients may be caused by Lyme carditis, a reversible condition. Prompt diagnosis and antibiotic treatment can prevent the need for unnecessary pacemaker implantation.
Area of Science:
- Cardiology
- Infectious Diseases
- Electrophysiology
Context:
- High-degree atrioventricular (AV) block in the elderly is typically due to irreversible cardiac conduction system degeneration.
- In younger individuals, reversible causes of AV block are more common and varied.
- Lyme carditis, a manifestation of Lyme borreliosis, is a rare but treatable cause of AV block.
Purpose:
- To highlight Lyme carditis as a critical, reversible differential diagnosis for AV block in specific patient populations.
- To emphasize the importance of considering infectious etiologies before pacemaker implantation.
- To guide clinicians on diagnostic and therapeutic strategies for suspected Lyme carditis.
Summary:
- Lyme carditis, caused by Borrelia burgdorferi, can present as high-degree AV block, particularly in young and middle-aged patients.
- A thorough evaluation for reversible causes, including Lyme carditis, is essential prior to pacemaker implantation.
- Positive serological tests in patients with intermediate to high pretest probability strongly suggest Lyme carditis, which is treatable with antibiotics.
Impact:
- Early diagnosis and antibiotic treatment of Lyme carditis can potentially avert the need for permanent pacemaker implantation.
- Increased awareness of Lyme carditis may lead to earlier diagnosis and improved patient outcomes.
- This understanding can refine clinical decision-making algorithms for AV block management.
Abstract:
In elderly patients high-degree atrioventricular (AV) block is often due to irreversible degeneration of the cardiac conduction system. Reversible causes must however be excluded prior to pacemaker implantation. In younger patients reversible causes are more likely, as well as more unusual etiologies. Lyme carditis is a rare, but reversible cause of AV block. It is a manifestation of Lyme borreliosis - an infectious disease caused by the bacteria Borrelia burgdorferi. Lyme carditis should particularly be considered in young and middle-aged patients with a high-degree AV block. When pretest probability is intermediate to high, a positive serological test makes the diagnosis of Lyme carditis highly likely. In these cases antibiotic treatment may revert the conduction disturbance, thus preventing unnecessary implantation of a permanent pacemaker.
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