Phase 4 Block of the Right Bundle Branch Suggesting His-Purkinje System Involvement in Lyme Carditis
[CanLyme Note: As new research unfolds we are discovering that borrelia other than Borrelia burgdorferi (Bb) are pathogenic to humans. Much research is required to garner a broader understanding of cardiovascular and other system involvement and presentation. Testing currently is too focused on Bb and even with that it has many limitations and inaccuracies resulting in many missed diagnoses or false negative results. Diagnosis is too focused on having to have had an EM rash.]
From: Heart Rhythm Case Reports
Lyme disease (LD) due to Borrelia burgdorferi infection causes a wide variety of signs and symptoms, including cardiac involvement termed Lyme carditis (LC).1, 2, 3 While uncommon, LC is a well-established cause of atrioventricular (AV) block, typically at the AV node level, with infrequent involvement of the infra-nodal conduction system.1
We describe an adolescent with symptomatic high-grade AV block and evidence of phase 4 right bundle branch block, a previously unreported manifestation of infra-nodal conduction system involvement in LC.