Ebstein's anomaly

Etiology

• maternal lithium ingestion during pregnancy

Pathology

• congenital anomaly of the tricuspid valve in which the cusps are thin with downward displacement of a portion of the valve below the AV ring (ventriculization of the right atrium)
• associated conditions
  • atrial septal defect: ostium secundum
  • patent foramen ovale
  • pre-excitation syndrome (WPW syndrome)

Clinical manifestations

• tricuspid regurgitation
  • mild to moderate if at all
  • results in holosystolic murmur at left sternal border that increases with respiration
• cool extremities, often with peripheral cyanosis, especially patients with concomitant ostium secundum
  • clubbing due to chronic hypoxemi
• one or more systolic clicks
• patients may present with neurological events

Diagnostic procedures

• electrocardiogram:
  • tall p waves
  • right bundle branch block
• electrophysiologic studies to delineate bypass tract if indicated

Radiology

• chest X-ray
  • narrow pedicle with enlarged globular silhouette
  • right atrial enlargement
  • lung fields normal or oligemic
• echocardiogram
• cardiac catherization generally unnecessary

More general terms

• congenital heart disease; congenital cyanotic heart disease
• valvular heart disease

Additional terms

• atrial septal defect (ASD)
• pre-excitation