The cardiovascular system begins developing in the third week as the heart starts beating in the fourth week. Between weeks 4-5, pharyngeal arches form and the aortic arches transform into the adult arterial arrangement between weeks 6-8. During this critical period of heart development from 20-50 days after fertilization, anomalies can occur in the development of the pharyngeal arteries and veins. Common anomalies include double aortic arch, right aortic arch, patent ductus arteriosus, and persistent fetal veins. Remnants of fetal vessels include the umbilical arteries, left umbilical vein, ductus venosus, and ductus arteriosus.

1. Development
of
arterial &venous
system

2. • CVS develops at 3rd
week.
• Heart starts to beat at the beginning of 4th
wk.
• Pharyngeal arches are formed during 4-5th
week.
• 6-8th
aortic arches are transformed into adult
arterial arrangement.
Critical period of heart development is between 20-
50 day after fertilization.

7. Anomalous development of
pharyngeal arteries
• Double aortic arch-
Characterized by vascular ring around the trachea &
esophagus.
• Right aortic arch
• Right subclavian artery arises from the last aortic
arch.(Retroesophageal right subclavian artery)

8. • Patent ductus caroticus
• Patent ductus venosus
common anomaly.
2/3 times more frequent in females.
• Segment of aortic may be missing.
• Coarctation of aorta.
preductal/postductal
10% of children with CHD
• Persistance/disappearance of certain parts of the
aortic arch.

14. Anomalies of Veins
• Double Superior vena Cava
• Left Superior Vena Cava
• Absence of hepatic segment of IVC
• Double Inferior Vena Cava
• Pre-ureteric Vena Cava

16. Vessels Remnant
• Umbilical arteries Medial umbilical ligaments
• Left umbilical vein Ligamentum teres of liver
• Ductus venosus Ligamentum venosum
• Ductus arteriosus Ligamentum arteriosum