1. Outflow Tract Development
Right Oblique View of Cut Heart – Beginning of the 5th Week
UNSW Embryology

2. Right and Left AV Canals
Right Oblique View of Cut Heart – Beginning of the 5th Week
Lumen of Conotruncus
Right and Left Atria
Right and Left AV Canals

3. Muscular Ventricular Septum Right and Left Ventricles
Right Oblique View of Cut Heart – Beginning of the 5th Week
Lumen of Conotruncus
Endocardial Cushions
Muscular Ventricular Septum
Right and Left Ventricles

5. Development of Truncal and Bulbar Endocardial Cushions

6. Development of Truncal and Bulbar Endocardial Cushions
Truncal Ridges
Bulbar Ridges

8. The ridges grow superiorly and inferiorly & fuse with the atrioventricular endocardial cushions and IV septum

9. The ridges grow superiorly and inferiorly & fuse with the atrioventricular endocardial cushions and IV septum

10. The ridges grow superiorly and inferiorly & fuse with the atrioventricular endocardial cushions and IV septum

11. The ridges grow superiorly and inferiorly & fuse with the atrioventricular endocardial cushions and IV septum

13. The pulmonary trunk and aorta develop from this division

14. Future Pulmonary Trunk
The pulmonary trunk and aorta develop from this division
Future Pulmonary Trunk
Future Aorta

15. The pulmonary trunk and aorta develop from this division

16. The pulmonary trunk and aorta develop from this division

17. The pulmonary trunk and aorta develop from this division

18. The pulmonary trunk and aorta develop from this division