Atrioventricular Septal Defect

Relevant Physiology

Etiology

• Defect of the AV endocardial cushion
• 25% in Trisomy 21 - Down Syndrome (lack of it doesn’t rule out trisomy 21) → Trisomy 21 - Down Syndrome

Pathogenesis

• L→ R shunt

1. Primum ASD ASD
2. Inlet VSD VSD
3. Common AV valve

Prognosis/Disease Course/Complications

• Variable, depending on the lesions and their sizes
• Eisenmenger Syndrome over time
• Can develope !CHF (H+W)

Classifications

• Complete (all 3 components)
• Partial (no inlet VSD)
• Unbalanced (most of the common valve is over one ventricule)

Presentation