The Cardiovascular System (Part II)

黃敏銓 [email protected] 解剖學暨細胞生物學研究所 1 Development of veins

Three paired veins drain into the tubular heart of a 4-week embryo

• Vitelline veins: poorly oxygenated blood from yolk sac • Umbilical veins: oxygenated blood from the primordial placenta • Common cardinal veins: poorly oxygenated blood from the body of the embryo

2 Three paired veins Cardinal veins 26 days Sinus venosus Pharyngeal arch arteries

Blue color

Vitelline vein Umbilical vein Umbilical vesicle (well-oxygenated)

3 Three paired veins enter into the sinus venosus

Left Right Dorsal view 24 days

4 Vitelline veins IVC, Hepatic veins & sinusoids, and portal vein

Left Right

Hepatic segment of IVC: right vitelline vein Hepatic veins: vitelline veins

Hepatic sinusoids Liver

Portal vein: vitelline veins

Dorsal view (7 weeks) Duodenum 5 Umbilical veins Umbilical vein : left umbilical vein

Left Right

7th week

(Ligamentum venosum)

Dorsal view 6 Anterior cardinal veins Brachiocephalic veins 7 weeks Anastomosis between anterior cardinal veins

Left Right

8 weeks Left brachiocephalic vein Right brachiocephalic vein

Dorsal view 7 Superior vena cava

(Oblique vein of left atrium)

Indian Pacing Electrophysiol. J.

Superior vena cava

Left Right anterior cardinal vein Right common cardinal vein Right

(Left horn of sinus venosus) 8 Dorsal view Left brachiocephalic vein Left superior intercostal vein

Oblique vein to coronary sinus Posterior cardinal veins: root of azygos v. and common iliac veins

6 weeks Adult

Azygos v. Posterior cardinal vein (mesonephroi)

Common iliac veins

10 Right Left Subcardinal veins and supracardinal veins replace and supplement posterior cardinal veins

Supracardinal v.

Posterior cardinal v. Subcardinal v.

Right Left

6 weeks 7 weeks 11 Subcardinal veins

IVC (prerenal seg.) Stem of L. renal v.

R. suprarenal v. L. suprarenal v.

Subcardinal vein R. gonadal v. L. gonadal v.

6 weeks Adult 12 Right Left Supracardinal veins

Azygos v. Hemiazygos v.

IVC (postrenal seg.) degeneration

8 weeks Right Adult Left

Supracardinal vein 13 Inferior vena cava (IVC)

Left Right

IVC (hepatic segment): R. vitelline vein

IVC (prerenal segment): R. subcardinal v.

IVC (renal segment): Subcardinal-supracardinal anastomosis

IVC (postrenal segment): R. supracardinal v.

14 Right Adult Left The primordial pulmonary vein develops in the dorsal wall of the left atrium Development of arteries

 Pharyngeal arch arteries  Dorsal aorta  Intersegmental arteries  Vitelline arteries  Umbilical arteries

16 Intersegmental arteries Pharyngeal arch arteries Dorsal aorta (Aortic arches) Umbilical artery

Pharyngeal arches

Aortic sac

4th-5th week (26 days) Vielline artery

17 Intersegmental arteries

• Neck: vertebral arteries • Thorax: intercostal arteries • Abdomen: – lumbar arteries – 5th pair: common iliac arteries • Sacrum: lateral sacral arteries • Caudal end of dorsal aorta: median sacral artery.

18 Vitelline arteries • Celiac trunk: foregut • Superior mesenteric artery: midgut • Inferior mesenteric artery: hindgut

19 Umbilical arteries

• Proximal parts – Umbilical artery (branch of Internal iliac arteries) – Superior vesical arteries • Distal parts – Medial umbilical ligaments

20 Derivatives of pharyngeal arch arteries

Pharyngeal arch arteries (Aortic arches)

21 Pharyngeal arches and pharyngeal arch arteries Pharyngeal arch arteries

26 days

22 Primordial pharyngeal arch arterial pattern is transformed into the final fetal arterial arrangement during the 8th week

(1st, 2nd pairs disappeared) 3rd, 4th, and 6th pharyngeal arch arteries

6 weeks 8 weeks 23 Derivatives of the 1st pair pharyngeal arch arteries

• Maxillary arteries – Ears, teeth, muscles of eyes and face • External carotid arteries Pharyngeal arch arteries

1st pair of pharyngeal arch arteries

24 Derivatives of the 2nd pair pharyngeal arch arteries Stems of the stapedial arteries

Stapedial artery: 第10週退化 Persistent stapedial artery: 異常

Pharyngeal arch arteries

2nd pair of pharyngeal arch arteries (dorsal part)

25 Derivatives of the 3rd pair pharyngeal arch arteries

6 weeks 7 weeks

Internal carotid artery

Common carotid artery

Pharyngeal arch arteries

26 Derivatives of the 4th pair pharyngeal arch arteries

1. Right: proximal part of right subclavian artery 2. Left: part of arch of aorta

1 1 Right subclavian artery 2 Left subclavian artery 2

Right dorsal aorta

7th intersegmental arteries

right left 27 Fate of 5th pair of pharyngeal arch arteries

• 50% embryos: rudimentary vessels – no vascular derivatives

• 50% embryos: no 5th pair arteries develop

28 Derivatives of the 6th pair pharyngeal arch arteries

Right: Proximal: right pulmonary artery (proximal) Distal: degeneration

Left: Proximal: left pulmonary artery (proximal) Distal: ductus arteriosus

29 Left recurrent laryngeal nerve hooks around the ligamentum arteriosum and aortic arch

30 Why the course of the recurrent laryngeal nerves differs? Pharyngeal arch arteries

6 weeks

ductus arteriosus

Child 31 8 weeks right left Right and left subclavian artery Arch of aorta

1 1 Right subclavian artery 2 Left subclavian artery 2

Right dorsal aorta

7th intersegmental arteries

right left right left

32 Aortic Arch Anomalies

• Coarctation of Aorta: 10% of CHD

• Double Aortic Arch

• Right Arch of Aorta

• Anomalous Right Subclavian Artery

33 Coarctation of Aorta

Male : Female≒2:1 70% cases : bicuspid aortic valve • Juxtaductal coarctation: 90% • Postductal coarctation • Preductal coarctation

Preductal coarctation

Postductal coarctation

Ductus arteriosus Ductus arteriosus 34 Collateral circulation during the fetal period in postductal coarctation

35 Preductal coarctation

Ductus arteriosus

Closure of DA in infant results in hypoperfusion and rapid deterioration

Treatment: infusion of prostaglandin E2 to re-open the ductus arteriosus

36 Double Aortic Arch Vascular ring around the trachea and esophagus

Large right arch of aorta

Small left arch of aorta

Normally involutes

37 Right arch of aorta

Area of abnormal involution

Retroesophageal right arch of aorta

Right arch of aorta

38 Anomalous Right Subclavian Artery

Abnormal involution Persistent portion of right dorsal aorta

Right subclavian artery

39 Six primary lymph sacs at the end of embryonic period

Begins to develop at the end of the 6th week

(2) Head, neck, upper limbs Cystic hygroma

(1) Primordial gut (1)

Lower trunk, lower limbs 40 7.5-week embryo 9-week embryo Right lymphatic duct

Right and left thoracic ducts

Thoracic duct Right Left Chyle cistern (cisterna chyli)