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Brain abscess caused by paradoxical embolization in Ebstein's anomaly
M T Lønnebakken1, G Greve, E Leirgul
1Department of Heart Disease, Haukeland University Hospital, 5021 Bergen, Norway. mai.tone.lonnebakken@helse-bergen.no
Summary
A young woman developed a brain abscess due to Streptococcus milleri. Undiagnosed Ebstein's anomaly and an atrial septal defect (ASD) likely caused paradoxical embolization, leading to the abscess.
Area of Science:
- Cardiology
- Neurology
- Infectious Diseases
Background:
- A 25-year-old woman presented with a Streptococcus milleri brain abscess.
- Her cardiac history was previously unremarkable.
Observation:
- Echocardiography revealed an undiagnosed moderate Ebstein's anomaly with apical displacement of the tricuspid valve's septal leaflet.
- A secundum atrial septal defect (ASD) with a left-to-right shunt was also identified.
Findings:
- The combination of Ebstein's anomaly and ASD can predispose to paradoxical embolization.
- Septic embolization from an extracardiac source is the most probable cause of the brain abscess.
Implications:
- Ebstein's anomaly may remain undiagnosed in adults with well-functioning right ventricles.
- This case highlights the importance of cardiac evaluation in unexplained brain abscesses, especially in the presence of congenital heart defects.
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