ATRIAL SEPTATION

ATRIAL SEPTATION

1. 1

   • SEPTUM PRIMUM grows inferiorly from the roof of thwe commom atrium
     • FUSION
       • ENDOCARDIAL CUSHION

2. 2

   • SEPTUM SECUNDUM forms to the right of the SP from the roof of the atriu. it does not fuse with the E.C
     • FORAMEN OVALE

3. ATRIAL SEPTAL DEFECT

   • SECUNDUM TYPE ASD
     • EXCESSIVE RESORPTION OF THE SP
     • AN UNDERDEVELOPMENT AND REDUCED SIZE OF THE SS
       • LEFT TO RIGHT SHUNT
         • NON-CYANOTIC
   • PRIMUM TYPE ASD
     • FAILURE OF THE SP TO FUSE WITH THE ENDOCARDIAL CUSHIONS
       • NORMALY FOSA OVALIS
         • LEFT TO RIGHT SHUNT
           • NON- SYANOTIC