The document discusses the development of the aorta and pulmonary trunk from embryonic structures. It notes that the arterial system develops from the pharyngeal arch arteries and primitive aortas. Specifically, it outlines that the aortic sac, left horn of the aortic sac, left fourth arch artery, and unfused left dorsal aorta develop into parts of the aorta. The right and left sixth arch arteries develop into the pulmonary trunk and ductus arteriosus. It provides details on derivatives of the pharyngeal arches and common congenital anomalies that can occur.

1. Development of aorta and
pulmonary trunk
To MBBS 1st year
By Dr. Laxman Khanal
Assistant Professor
Department of anatomy
BPKIHS
09-05-2016

2. Objectives
1. Should be able to list the developmental sources of arterial system.
2. Should be able to understand the origin of pharyngeal arch system.
3. Should be able to list the derivatives of pharyngeal arch arteries.
4. Should be able to explain important developmental anomalies.

3. Aorta
• Ascending aorta
• Arch of aorta
o Rt brachiocephalic trunk
o Lt common carotid artery
o Lt subclavian artery
• Descending aorta
o Oesophageal & Bronchial
o Post intercostal & subcostal
o Mediastinal
• Pulmonary trunk
o Rt & Lt pulmonary artery
Rt/Lt coronary arteries

4. Rt ventricle
Lt ventricle
Ascending aorta
Pulmonary trunk

5. Development of arterial system
Entire arterial system develops from either of two sources.
1. Pharyngeal arch arteries
2. Primitive aortas

7. ORAL PLATE
Source of arterial system
1.Ventral aortas ( fuses and form aortic sac)
2.Aortic arches (five pairs of arch arteries)
3.Dorsal aortas (fused and unfused portion)

12. Maxillary artery
Stapedial artery
Hyoid artery

13. 7th Cervical Intersegmental artery

14. Dorsal and ventral
parts of aortic sac

15. Ductus arteriosus
parts obliterated
• B/L carotid duct
• Right dorsal aorta beyond 4th arch
• Right distal part of 6th arch

16. Ventral part of aortic sac
Left horn of aortic sac
Left 4th arch artery
Left part of dorsal aorta
Fused portion of dorsal aorta

18. Aorta development
• Truncus arteriosus
• Aortic sac
• Left horn of aortic sac
• Left fourth arch artery
• Unfused left dorsal aorta
• Fused dorsal aorta

19. Relationship of recurrent
laryngeal nerve

20. Source Derivatives
Aortic sac Proximal part of arch of aorta
Horns of aortic sac Right- right brachiocephalic trunk
Left- part of arch of aorta
3rd arch artery Common carotid artery
Internal carotid artery (+upper dorsal aorta)
External carotid artery ( from arterial bud)
4th arch artery Rt- Rt subclavian (+7th cervical intersegmental artery)
Lt- arch of aorta
6th arch Rt- Rt. pulmonary artery
Lt- Lt pulmonary artery
- Ductus arteriosus
?
?
?
?
?

21. Patent ductus arteriosus
Pulmonary congestion
Causes
• Hypoxia
• Prostaglandin E

22. Preductal
• Less common
• DA remain patent
Postductal
• More common
• DA obliterated
• Rib notching
• Differential pressure
Coarctation of aorta

23. Rib notching (radiographic sign)
Due to enlargement of
anastomotic channel between
ant and posterior intercostal
arteries.

24. Abnormal origin of Rt subclavian artery
Rt 4th arch obliterates
Rt dorsal aorta persists

25. Double aortic arch
Rt dorsal aorta between 7th
interssegmetal artery and fused
dorsal aorta persists.
Vascular ring
• Dysphagia
• Difficulty in breathing

27. Q. All are the direct branches of aorta except.
a.Right brachiocephalic trunk b. left brachiocephalic trunk
c. Left common carotid artery d. left subclavian artery
Q. Which of the following arterial malformations is very common in
premature infants?
(A) Patent ductus arteriosus (B) Coarctation of the aorta
(C) Abnormal right subclavian artery (D) Double aortic arch
Q. Ascending aorta and pulmonary trunk are derivatives of.
a. Ductus arteriosus b. Dorsal aorta
c. Aortic sac d. Truncus arteriosus

28. Q. A 9-year-old boy has no pulse in the femoral artery, increased blood
pressure in the arteries of the upper extremity, and enlarged intercostal veins,
Which of the following abnormalities would be suspected?
a. Preductal coarctation of aorta b. double aortic arch
c. Postductal coarctation of aorta d. patent ductus arteriosus
Q. Ductus arteriosus is the derivatives of.
a. Rt 6th arch artery b. Lt 6th arch artery
c. Ductus caroticus d. Lt 4th arch artery
Q. Right recurrent laryngeal nerve hooks around.
a. Rt subclavian artery b. Rt pulmonary artery
c. Arch of aorta d. Rt brachiocephalic trunk