Cvs dev
- 2. Embryonic Blood Vessels • By the beginning of the 4th week, an extensive network of blood vessels is formed throughout the embryonic body • The heart begins to beat on 21st or 22nd day, and blood begins to circulate. • This makes the CVS to be the first system in the body to reach the functional state • The embryonic heartbeat can be detected ultrasono- graphically during the 5th week
- 5. Aortic Arches • 1st arteries to appear is primitive aortae consist of a portion lying ventral to foregut( ventral aorta) , an arched portion (1st aortic arch) , & dorsal portion lying dorsal to the gut ( dorsal aorta) • The ventral aorta partially fuse to form aortic sac , unfused part remaining as the right & left horn of aortic sac. • The aortic arches arise from the aortic sac and terminate in the dorsal aorta of the ipsilateral side
- 6. Aortic Arches • Though six pairs of aortic arches usually develop • All are not present at the same time • By the time the sixth pair of aortic arches has formed, the first two pairs disappear • During the eighth week, the aortic arch pattern is transformed to final fetal arterial arrangement • In the region of aortic arches, the dorsal aortae remain paired, but caudal to this region they fuse to form a single median vessel
- 7. Changes in the original aortic arch system
- 8. Changes in the original aortic arch system • Obliteration of: Most of the 1st & 2nd arches 5th arches completely Distal part of the right sixth arch The segment of both dorsal aortae lying between the 3rd & 4th arches ( ductus caroticus ) The segment of right aorta lying between the 7th intersegmental artery & the fused dorsal aortae
- 9. Derivatives of Aortic Arches
- 10. First Pair • Largely disappear • Dorsal part persists as the maxillary arteries which supply the ear, teeth and muscles of the eyes and face • May give rise to the external carotid artery The first arch is obliterated before the 6th arch is formed
- 11. Second Pair • Largely disappear • Dorsal part persists as the hyoid and stapedial arteries
- 12. Third Pair • Proximal part: forms the common carotid arteries • Distal part: joins the dorsal aortae to form the internal carotid arteries
- 13. Third Pair • Each third arch artery gives off a bud that grows cranially to form the External carotid artery
- 14. Fifth Pair • Disappears completely with NO vascular derivatives
- 15. The fate of 4 & 6th pairs of aortic arches differs on the right and left side
- 16. Aortic sac • Aortic sac & left horn : becomes the proximal segment of the Aortic arch • Right horn : becomes the Brachiocephalic artery
- 17. Fourth Pair • RIGHT: Becomes the proximal part of the right subclavian artery • LEFT: Forms part of the arch of aorta
- 18. Arch of Aorta Derived as: • Proximal segment from aortic sac • Middle segment from the left horn of aortic sac • Distal segment from the left 4th aortic arch
- 19. Subclavian Artery • The right subclavian artery formed from the: Right horn of aortic sac & Right 4th aortic arch Right 7th intersegmental artery • The left subclavian artery formed from the left 7th intersegmental artery
- 20. Sixth Pair • RIGHT: :- Proximal part: persists as the proximal part of the right pulmonary artery :- Distal part: degenerates • LEFT: :- Proximal part: persists as the proximal part of the left pulmonary artery :- Distal part: forms ductus arteriosus, a shunt between pulmonary artery and dorsal aorta
- 22. ADULT DERIVATIVES OF FETAL VESSELS Umbilical vein becomes the ligamentum teres hepatis. Umbilical arteries( rt <) :-- • proximal part superior vesicle arteries • distal part medial umbilical ligaments. . Ductus venosus ligamentum venosum, Foramen ovale fossa ovalis Ductus arteriosus ligamentum arteriosum
- 23. 14 Feb 2009 23 Anomalies of Aortic Arches Patent ductus arteriosus
- 24. 14 Feb 2009 24 Coarctation of aorta Types
- 25. 14 Feb 2009 25 Abnormal origin of right subclavian artery: Types
- 26. 14 Feb 2009 26 Double aortic arch
- 27. 14 Feb 2009 27 Right aortic arch
- 28. 14 Feb 2009 28 Interrupted aortic arch
- 29. 14 Feb 2009 29 Persistent ductus caroticus
- 30. 14 Feb 2009 30 Thank You
- 31. Aortic Arch Anomalies • Coarctation of aorta or constriction of aorta • Double aortic arch • Right arch of aorta
- 32. Coarctation of aorta • Characterized by narrowing of aorta • More common in males • Classified as Preductal & Postductal types, but mostly the constriction lies distal to the origin of subclavian artery opposite the ductus arteriosus (Juxtaductal )
- 33. Preductal
- 34. Preductal type • Preductal type: Less common. The narrowing is proximal to the ductus arteriosus. If severe, blood flow to the aorta distal to the narrowing (supplying lower body) depends on a patent ductus arteriosus, and hence its closure can be life-threatening.
- 35. Postductal
- 36. Postductal
- 37. Postductal type • Postductal type Most common. The narrowing is distal to the ductus arteriosus. The ductus usually remains open to communicate pulmonary artery with the descending aorta Even with an open ductus arteriosus blood flow to the lower body can be impaired. Allows development of collateral circulation during the fetal period. It is associated with notching of the ribs, hypertension in the upper extremities, and weak pulses in the lower extremities.
- 38. Right Arch of Aorta • Occurs when the entire right aortic arch persists &the segment of left dorsal aorta distal to the 7th intersegmental artery involutes
- 39. Double Arch of Aorta • Usually the right arch is larger and passes posterior to the esophagus • The right common carotid and subclavian arteries arise separately from right arch
- 40. Double Arch of Aorta • Characterized by a vascular ring encircling the trachea and esophagus, usually causing compression of both structures. • The degree of compression varies
- 41. Thank you
- 42. The descending aorta. • The main embryonic vessels are the paired dorsal aortae, which receive blood from the heart and distribute it to body tissues • The dorsal aortae fuse caudally during the fourth week, forming a single median vessel, the descending aorta.
- 43. The descending aorta gives the following branches: Lateral segmental Ventral segmental Dorsal intersegmental • The caudal end of the descending aorta becomes the median sacral artery
- 44. Lateral Segmental Arteries Supply the: Diaphragm Kidneys Adrenal glands Gonads These vessels become the phrenic, renal, middle suprarenal, and gonadal arteries of the adult.
- 45. Ventral Segmental Arteries: Supply the: Yolk sac (Vitelline arteries) Allantois (Umbilical arteries) Embryonic part of placenta (Chorionic arteries)
- 46. Vitelline arteries • Supply the yolk sac and the primitive gut • Three major arteries remain as the: Celiac trunk (artery of foregut) Superior mesenteric artery (artery of midgut) Inferior mesenteric artery (artery of hindgut).
- 47. Umbilical arteries • Pass through the connecting stalk in close association with the allantois • Become continuous with the chorionic blood vessels. • Carry poorly oxygented blood to the placenta • Derivatives: Proximal parts: persist as the superior vesical arteries, which supply the urinary bladder Distal parts: obliterate after birth and become the median umbilical ligaments
- 48. Dorsal intersegmental arteries Somatic branches About thirty or more pairs arise at serial segmental levels, run between the somites Supply the body wall, limbs, brain and spinal cord.
- 49. Dorsal intersegmental arteries • Derivatives: In cervical region: join to form the vertebral artery. The 7th pair contributes to the subclavian arteries. In thoracic region: become the posterior intercostal arteries In abdominal region: become the lumbar arteries. The 5th pair remains as the common iliac artery In sacral region: form the lateral sacral arteries
- 50. Development of veins Vitelline veins return poorly oxygenated blood from yolk sac to the sinus venosus of heart. Umbilical veins carry well-oxygenated blood from primordial placenta to sinus venosus. Common cardinal veins carry poorly oxygenated blood from body of embryo to sinus venosus
- 51. Vitelline Veins
- 52. Vitelline Veins Lie in the yolk stalk, they carry poorly oxygenated blood from yolk sac to sinus venosus passing through septum transversum. In the region of developing liver in septum transversum, hepatic sinusoids develop from vitelline veins, Hepatic veins develop from remains of right vetilline vein. Proximal part of right vitelline vein form hepatic part of I.V.C. Proximal left vitelline vein degenerates . Portal vein develops from an anastomotic network of distal parts of right & left vitelline veins around the duodenum.
- 53. Umbilical Veins
- 54. Umbilical Veins They carry well-oxygenate blood from placenta to sinus venosus. As the liver develops, umbilical veins lose their connection with heart. Right umbilical vein disappears completely. Proximal (cranial) part of left umbilical vein between liver & sinus venosus degenerates. Distal (caudal) part of left umbilical vein persist and connected with I.V.C through a large venous shunt- ductus venosus , so blood pass directly from placenta to heart.
- 55. Umbilical Veins • When the portal vein develops the ductus venosus connects the left branch of portal vein to hepatic portion of IVC. • Left umbilical vein connects with the left branch of the portal vein inside the liver. • After birth the left umbilical vein and ductus venosus are obliterated and form the ligamentum teres hepatis and ligamentum venosum , respectively .
- 56. Cardinal veins Cardinal veins constitute the main venous drainage of the embryo. Anterior & posterior cardinal veins drain cranial & caudal parts of embryo ,respectively. 4th week, anterior & posterior cardinal veins join the common cardinal veins, which enter sinus venosus
- 59. Anterior cardinal veins The anterior cardinal veins are joined by subclavian vein( drains the fore limb). Proximal to subclavian vein , rt & lt ant. Cardinal veins are interconnected by transverse anastomosis. SVC derived from • right common cardinal vein • Right ant. Cardinal vein( distal to transverse anastomosis ) Right brachiocephalic vein – Right ant. Cardinal vein(proximal to transverse anastomosis )
- 60. Anterior cardinal veins left brachiocephalic vein derived from • the transverse anastomosis shunt between anterior cardinal veins • left anterior cardinal vein ( proximal to transverse anastomosis ) caudal part of left anterior cardinal vein degenerates. Internal jugular veins develop from the part of anterior cardinal veins cranial to their junction with the subclavian vein .
- 62. Posterior cardinal veins • During the fifth to the seventh week a number of additional veins are formed: • (a) the subcardinal veins, which mainly drain the kidneys; • (b) the supracardinal veins, which drain the body wall by way of the intercostal veins, taking over the functions of the posterior cardinal veins • (c) the sacrocardinal veins, which drain the lower extremities;
- 63. Posterior cardinal veins • Formation of the vena cava system is characterized by the appearance of anastomoses between left and right in such a manner that the blood from the left is channeled to the right side. • As a result, right veins enlarge while left veins become small and may disappear.
- 64. Fate of Subcardinal veins
- 65. Fate of Subcardinal veins Left subcardinal vein cranial to the anastomosis disappears leaving small left suprarenal vein, while caudal to anastomosis it becomes left gonadal vein. Right subcardinal vein cranial to the anastomosis forms the pre-renal part of I.V.C. + right suprarenal vein, while caudal to the anastomosis it develops into right gonadal vein. Right & left subcardinal vein anastomosis forms left renal veins + renal part of I.V.C.
- 66. Fate of Supracardinal veins
- 67. Fate of Supracardinal veins The middle part of the 2 veins in the region of kidney disappears. • The 4th to 11th right intercostal veins empty into the right supracardinal vein, which together with a portion of the posterior cardinal vein forms the azygos vein • On the left the 4th to 7th intercostal veins enter into the left supracardinal vein, and the left supracardinal vein, then known as the hemiazygos vein .
- 68. Development of I.V.C & Azygos vein
- 69. Fate of sacrocardinal veins • The anastomosis between the sacrocardinal veins forms the left common iliac vein . • Caudal part of right sacrocardinal vein veins form the right common iliac vein . • The cranial right sacrocardinal vein becomes the sacrocardinal segment of the inferior vena cava • The inferior vena cava, consisting of hepatic, renal, and sacrocardinal segments, is complete.
- 70. Development of I.V.C Hepatic part : develops from hepatic vein (from proximal part of right vitelline vein) + hepatic sinusoids. Pre-renal part : develops from right subcardinal vein. Renal part : develops from Right & left subcardinal vein anastomosis Sacrocardinal part : develops from right sacrocardinal vein above the anastomosis.
- 71. END
- 73. Atrial Septal defects (ASD) • There are 4 types of clinically significant types of ASD : • 1-Ostium secundum defect. ( excessive resorption of the septum primum ) • 2-Endocardial cushion defect. (with ostium primum defect , failure of development of S. secundum) • 3- Patent oval foramen • 4-Common atrium…. Rare cardiac defect ,in which the interatrial septum is absent due to failure of septum primum & septum secundum to develop.
- 75. Atrial Septal defects (ASD) • Ostium secundum defect – most common type of ASD • Infant & children are usually asymptomatic. • Patient is thin built. • Spontaneous closure of secundum defect have occurs in 40%of patient in first 4 year of life. • The most serious abnormality in this group is complete absence of the atrial septum . This condition, known as common atrium .
- 76. Ventricular Septal Defects (VSDs)
- 77. Ventricular Septal Defects (VSDs):
- 78. Ventricular Septal Defects (VSDs): Membranous VSD …. Is the most common type. Results from incomplete closure of IV foramen due to failure of development of memb. part of IV septum. Large VSDs with excessive pulmonary blood flow & pulm.hypertension result in dyspnea (difficult breathing) + heart failure.
- 80. Patent Ductus Arteriosus • Before birth, the aorta and the pulmonary artery are normally connected by a blood vessel called the ductus arteriosus, which is an essential part of the fetal circulation. • In some babies, the ductus arteriosus remains open (patent) , after birth . • This allows blood to flow directly from the aorta into the pulmonary artery, which can put a strain on the heart and increase pressure in the pulmonary circulation .
- 81. Patent Ductus Arteriosus • Pt may become symtomatic in early life. • Neonates develop congestive cardiac failure (CCF) around 6 – 10 week of life . • Older children develop palpitation and frequent chest infection .
- 83. Tetralogy of Fallot It contains 4 cardiac defects : 1- Pulmonary stenosis (obstruction of right ventricular outflow). 2- Ventricular Septal Defect (VSD). 3- Dextroposition of aorta (overriding aorta). 4- Right ventricular hypertrophy. cyanosis is one of the obvious signs of tetralogy .
- 84. Tetralogy of Fallot • Pt of TOF may become symtomatic any time after birth . • Commenest symptom- dyspnea on exertion& exercise intolerance. • Anoxic spells (paroxysmal attacks of dyspnea ) • Cyanosis present at birth or appear some year after birth. • X-Ray – oligemic lung field , Cor- en – sabot appearance
- 85. Trilogy of Fallot • Pulmonary Stenosis • ASD • Right ventricular hypertrophy
- 86. Pink fallot’s • V.S.D • Mild Pulmonary stenosis