Cardiovascular System - Revision history

WikiSysop at 07:38, 7 June 2025

2025-06-07T07:38:20Z

← Older revision		Revision as of 07:38, 7 June 2025
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	{{Stub Notice}}		{{Stub Notice}}


	=General=		=General=

WikiSysop at 07:22, 7 June 2025

2025-06-07T07:22:16Z

← Older revision		Revision as of 07:22, 7 June 2025
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			{{Stub Notice}}

	=General=		=General=

WikiSysop at 10:49, 3 June 2025

2025-06-03T10:49:03Z

← Older revision		Revision as of 10:49, 3 June 2025
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	* R dorsal Ao regresses leaving the L dorsal Ao as the descending aorta		* R dorsal Ao regresses leaving the L dorsal Ao as the descending aorta

	=~~=FORMATION OF THE VENOUS SYSTEM=~~=		=Formation of the Venous System=

	(Fig. 10)		(Fig. 10)

WikiSysop at 10:43, 3 June 2025

2025-06-03T10:43:15Z

← Older revision		Revision as of 10:43, 3 June 2025
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	==~~FORMATION OF THE HEART LOOP~~==		==Formation of the Heart Loop==

	(Fig. 2)		(Fig. 2)
Line 28:		Line 28:
	* Mechanism of cardiac looping not well understood		* Mechanism of cardiac looping not well understood

	==~~FORMATION OF THE EMBRYONIC VENTRICLES~~==		==Formation of the Embryonic Ventricles==

	(Fig. 3)		(Fig. 3)
Line 44:		Line 44:
	bulboventricular fange		bulboventricular fange

	==~~DEVELOPMENT OF THE SINUS VENOSUS~~==		==Development of the Sinus Venosis==

	(Fig. 4)		(Fig. 4)
Line 60:		Line 60:
	sinus horns		sinus horns

	==~~FORMATION OF THE CARDIAC SEPTA~~==		==Formation of the Cardiac Septa==

	umbilical vein		umbilical vein

WikiSysop at 10:39, 3 June 2025

2025-06-03T10:39:59Z

← Older revision		Revision as of 10:39, 3 June 2025
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	=~~=GENERAL=~~=		=General=

	* 1st functional organ system in the embryo		* 1st functional organ system in the embryo
Line 7:		Line 7:


	=~~=DEVELOPMENT OF THE HEART=~~=		=Development of the Heart=

	(Fig. 1)		(Fig. 1)

WikiSysop at 10:35, 3 June 2025

2025-06-03T10:35:56Z

← Older revision		Revision as of 10:35, 3 June 2025
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	~~{{Stub Notice}}~~


	==GENERAL==		==GENERAL==

Line 178:		Line 175:
	* SVC is formed by the junction of the R common cardinal vein & the proximal portion of the R anterio cardinal vein		* SVC is formed by the junction of the R common cardinal vein & the proximal portion of the R anterio cardinal vein

	~~<b>Relevant Article Depot:</b>~~
			{{Stub Notice}}


	[[TYK2\| Test Your Knowledge]]:increase in mean airway pressure effect on complex cardiac anatomy		[[TYK2\| Test Your Knowledge]]:increase in mean airway pressure effect on complex cardiac anatomy

WikiSysop at 10:24, 3 June 2025

2025-06-03T10:24:25Z

← Older revision		Revision as of 10:24, 3 June 2025
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	=FORMATION OF THE HEART LOOP=		==FORMATION OF THE HEART LOOP==

	(Fig. 2)		(Fig. 2)

	# Intrapericardial = bulboventricular portion of heart		# Intrapericardial = bulboventricular portion of heart
	# Extrapericardial = atrium/sinus venous + Ao roots		# Extrapericardial = atrium/sinus venous + Ao roots
Line 29:		Line 31:
	* Mechanism of cardiac looping not well understood		* Mechanism of cardiac looping not well understood

	=FORMATION OF THE EMBRYONIC VENTRICLES=		==FORMATION OF THE EMBRYONIC VENTRICLES==

	(Fig. 3)		(Fig. 3)

	truncus arteriosus		truncus arteriosus
	* After looping, the cardiac tube develops local expansions which are precursors to the cardiac chambers		* After looping, the cardiac tube develops local expansions which are precursors to the cardiac chambers
Line 43:		Line 47:
	bulboventricular fange		bulboventricular fange

	=DEVELOPMENT OF THE SINUS VENOSUS=		==DEVELOPMENT OF THE SINUS VENOSUS==

	(Fig. 4)		(Fig. 4)

	* The sinus venous consists of three parts:		* The sinus venous consists of three parts:
	Central unpaired portion proximal to the atrium		Central unpaired portion proximal to the atrium
Line 57:		Line 63:
	sinus horns		sinus horns

	=FORMATION OF THE CARDIAC SEPTA=		==FORMATION OF THE CARDIAC SEPTA==

	umbilical vein		umbilical vein
	vilelline vein		vilelline vein
	left ventricle		left ventricle
	~~veng~~ cava		vena cava
	~~night~~ ventricle		right ventricle

	* Major septa in the heart are formed between the 27th & 37th day; these chambers		* Major septa in the heart are formed between the 27th & 37th day; these chambers
	involve either active fusion of cushions or passive expansion of the cardiac		involve either active fusion of cushions or passive expansion of the cardiac
Line 79:		Line 87:
	Cushion		Cushion

	=THE ATRIOVENTRICULAR CANAL=		==THE ATRIOVENTRICULAR CANAL==

	(Fig. 6)		(Fig. 6)

	* AV canal septation occurs by growth of the endocardial cushions. The anterior (superior) and posterior (inferior) AV cushion extend into the		* AV canal septation occurs by growth of the endocardial cushions. The anterior (superior) and posterior (inferior) AV cushion extend into the
	ant endocardial cushion		ant endocardial cushion
Line 88:		Line 98:
	Cushion R of septum primum = septal leaflet of TV + crest of IVS		Cushion R of septum primum = septal leaflet of TV + crest of IVS

	=MUSCULAR INTRAVENTRICULAR SEPTUM FORMATION=		==MUSCULAR INTRAVENTRICULAR SEPTUM FORMATION==

	(Fig. 7)		(Fig. 7)

	* Muscular IVS formed by two processes:		* Muscular IVS formed by two processes:
	Medial walls of the expanding RV/LV oppose and fuse together		Medial walls of the expanding RV/LV oppose and fuse together
Line 95:		Line 107:
	* Primary IV foramen between RV/LV never closes and forms LV outflow tract		* Primary IV foramen between RV/LV never closes and forms LV outflow tract

	=CONOTRUNCAL SEPTATION=		==CONOTRUNCAL SEPTATION==

	(Fig. 8)		(Fig. 8)

	* Truncus arteriosus of the embryonic heart is divided by conotruncal cushions		* Truncus arteriosus of the embryonic heart is divided by conotruncal cushions
	sentum primum		sentum primum
Line 108:		Line 122:
	* The membranous IVS forms after completion of septation. Part of the EC cushion located between the septum primum & ventricular septum thins and forms the membranous septum		* The membranous IVS forms after completion of septation. Part of the EC cushion located between the septum primum & ventricular septum thins and forms the membranous septum

	=FORMATION OF THE AV VALVES=		==FORMATION OF THE AV VALVES==

	* AV valves are derived from EC cushion, endothelium, and ventricular tissue.		* AV valves are derived from EC cushion, endothelium, and ventricular tissue.
	A skirt of ventricular tissue covered		A skirt of ventricular tissue covered
Line 116:		Line 131:
	* Tricuspid valve forms from EC cushion, conus septum (= the conal papillary muscle + medial portion of the anterior cusp) and ventricular muscle		* Tricuspid valve forms from EC cushion, conus septum (= the conal papillary muscle + medial portion of the anterior cusp) and ventricular muscle

	=FORMATION OF THE SEMILUNAR VALVES=		==FORMATION OF THE SEMILUNAR VALVES==

	* Semilunar valve form at the interface of the truncal cushions and the Ao/PA septum. Initially seen as paired tubercles in the septated truncus, a 3rd tubercle appears & by hollowing of the upper surface the Ao/PA valves form		* Semilunar valve form at the interface of the truncal cushions and the Ao/PA septum. Initially seen as paired tubercles in the septated truncus, a 3rd tubercle appears & by hollowing of the upper surface the Ao/PA valves form

	=FORMATION OF THE ARTERIAL SYSTEM=		==FORMATION OF THE ARTERIAL SYSTEM==

	* Initial arterial system = blood islands that coalese to form vessels. Ist		* Initial arterial system = blood islands that coalese to form vessels. Ist
	major embryonic vessels = dorsal aortae which form along the axis of the		major embryonic vessels = dorsal aortae which form along the axis of the
Line 126:		Line 143:
	junction is the Ao sac. This sac contributes to the formation of the 6 paired Ao arches		junction is the Ao sac. This sac contributes to the formation of the 6 paired Ao arches

	=SELECTION OF AORTIC ARCHES=		==SELECTION OF AORTIC ARCHES==

	(Fig. 9)		(Fig. 9)

	* 1st Arch = Regresses except small portion - maxillary artery		* 1st Arch = Regresses except small portion - maxillary artery
	* 2nd Arch = Regresses		* 2nd Arch = Regresses
Line 141:		Line 160:
	* R dorsal Ao regresses leaving the L dorsal Ao as the descending aorta		* R dorsal Ao regresses leaving the L dorsal Ao as the descending aorta

	=FORMATION OF THE VENOUS SYSTEM=		==FORMATION OF THE VENOUS SYSTEM==

	(Fig. 10)		(Fig. 10)

	* 3 pair of veins form the major veins in the embryo:		* 3 pair of veins form the major veins in the embryo:
	Cardinal veins = drain the body of the embryo w/ the		Cardinal veins = drain the body of the embryo w/ the
Line 151:		Line 172:
	both sides of the liver.Both veins regresses except for L umbilical vein which becomes the ductus venosus		both sides of the liver.Both veins regresses except for L umbilical vein which becomes the ductus venosus

	=VENA CAVAE=		==VENA CAVAE==

	* Formed from the cardinal & subcardinal veins which together enlarge to form the hepatocardinal channel. After anastimosis w/ renal veins and regression of multiple branches, remaining		* Formed from the cardinal & subcardinal veins which together enlarge to form the hepatocardinal channel. After anastimosis w/ renal veins and regression of multiple branches, remaining
	portion = IVC		portion = IVC

WikiSysop at 10:20, 3 June 2025

2025-06-03T10:20:11Z

← Older revision		Revision as of 10:20, 3 June 2025
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	=GENERAL=		==GENERAL==

	* 1st functional organ system in the embryo		* 1st functional organ system in the embryo
	* Cardiac pathology during development is either genetic, enviornmental or combination of both		* Cardiac pathology during development is either genetic, enviornmental or combination of both
Line 9:		Line 10:


	=DEVELOPMENT OF THE HEART=		==DEVELOPMENT OF THE HEART==

	(Fig. 1)		(Fig. 1)

	* Mechamisms that initiate formation of the heart are not well understood; however the heart tube position is initially determined by brain growth		* Mechamisms that initiate formation of the heart are not well understood; however the heart tube position is initially determined by brain growth
	* Formation of the neural tube by folding causes fusion of the heart tube in the midline, to become a single endocardial tube		* Formation of the neural tube by folding causes fusion of the heart tube in the midline, to become a single endocardial tube

WikiSysop at 10:15, 3 June 2025

2025-06-03T10:15:37Z

← Older revision		Revision as of 10:15, 3 June 2025
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	==GENERAL==		=GENERAL=
	* 1st functional organ system in the embryo		* 1st functional organ system in the embryo
	* Cardiac pathology during development is either genetic, enviornmental or combination of both		* Cardiac pathology during development is either genetic, enviornmental or combination of both
Line 9:		Line 9:


	==DEVELOPMENT OF THE HEART==		=DEVELOPMENT OF THE HEART=
	(Fig. 1)		(Fig. 1)
	* Mechamisms that initiate formation of the heart are not well understood; however the heart tube position is initially determined by brain growth		* Mechamisms that initiate formation of the heart are not well understood; however the heart tube position is initially determined by brain growth
Line 17:		Line 17:


	==FORMATION OF THE HEART LOOP==		=FORMATION OF THE HEART LOOP=
	(Fig. 2)		(Fig. 2)
	# Intrapericardial = bulboventricular portion of heart		# Intrapericardial = bulboventricular portion of heart
Line 26:		Line 26:
	* Mechanism of cardiac looping not well understood		* Mechanism of cardiac looping not well understood

	==FORMATION OF THE EMBRYONIC VENTRICLES==		=FORMATION OF THE EMBRYONIC VENTRICLES=
	(Fig. 3)		(Fig. 3)
	truncus arteriosus		truncus arteriosus
Line 40:		Line 40:
	bulboventricular fange		bulboventricular fange

	==DEVELOPMENT OF THE SINUS VENOSUS==		=DEVELOPMENT OF THE SINUS VENOSUS=
	(Fig. 4)		(Fig. 4)
	* The sinus venous consists of three parts:		* The sinus venous consists of three parts:
Line 54:		Line 54:
	sinus horns		sinus horns

	==FORMATION OF THE CARDIAC SEPTA==		=FORMATION OF THE CARDIAC SEPTA=
	umbilical vein		umbilical vein
	vilelline vein		vilelline vein
Line 76:		Line 76:
	Cushion		Cushion

	==THE ATRIOVENTRICULAR CANAL==		=THE ATRIOVENTRICULAR CANAL=
	(Fig. 6)		(Fig. 6)
	* AV canal septation occurs by growth of the endocardial cushions. The anterior (superior) and posterior (inferior) AV cushion extend into the		* AV canal septation occurs by growth of the endocardial cushions. The anterior (superior) and posterior (inferior) AV cushion extend into the
Line 85:		Line 85:
	Cushion R of septum primum = septal leaflet of TV + crest of IVS		Cushion R of septum primum = septal leaflet of TV + crest of IVS

	==MUSCULAR INTRAVENTRICULAR SEPTUM FORMATION==		=MUSCULAR INTRAVENTRICULAR SEPTUM FORMATION=
	(Fig. 7)		(Fig. 7)
	* Muscular IVS formed by two processes:		* Muscular IVS formed by two processes:
Line 92:		Line 92:
	* Primary IV foramen between RV/LV never closes and forms LV outflow tract		* Primary IV foramen between RV/LV never closes and forms LV outflow tract

	==CONOTRUNCAL SEPTATION==		=CONOTRUNCAL SEPTATION=
	(Fig. 8)		(Fig. 8)
	* Truncus arteriosus of the embryonic heart is divided by conotruncal cushions		* Truncus arteriosus of the embryonic heart is divided by conotruncal cushions
Line 105:		Line 105:
	* The membranous IVS forms after completion of septation. Part of the EC cushion located between the septum primum & ventricular septum thins and forms the membranous septum		* The membranous IVS forms after completion of septation. Part of the EC cushion located between the septum primum & ventricular septum thins and forms the membranous septum

	==FORMATION OF THE AV VALVES==		=FORMATION OF THE AV VALVES=
	* AV valves are derived from EC cushion, endothelium, and ventricular tissue.		* AV valves are derived from EC cushion, endothelium, and ventricular tissue.
	A skirt of ventricular tissue covered		A skirt of ventricular tissue covered
Line 113:		Line 113:
	* Tricuspid valve forms from EC cushion, conus septum (= the conal papillary muscle + medial portion of the anterior cusp) and ventricular muscle		* Tricuspid valve forms from EC cushion, conus septum (= the conal papillary muscle + medial portion of the anterior cusp) and ventricular muscle

	==FORMATION OF THE SEMILUNAR VALVES==		=FORMATION OF THE SEMILUNAR VALVES=
	* Semilunar valve form at the interface of the truncal cushions and the Ao/PA septum. Initially seen as paired tubercles in the septated truncus, a 3rd tubercle appears & by hollowing of the upper surface the Ao/PA valves form		* Semilunar valve form at the interface of the truncal cushions and the Ao/PA septum. Initially seen as paired tubercles in the septated truncus, a 3rd tubercle appears & by hollowing of the upper surface the Ao/PA valves form

	==FORMATION OF THE ARTERIAL SYSTEM==		=FORMATION OF THE ARTERIAL SYSTEM=
	* Initial arterial system = blood islands that coalese to form vessels. Ist		* Initial arterial system = blood islands that coalese to form vessels. Ist
	major embryonic vessels = dorsal aortae which form along the axis of the		major embryonic vessels = dorsal aortae which form along the axis of the
Line 123:		Line 123:
	junction is the Ao sac. This sac contributes to the formation of the 6 paired Ao arches		junction is the Ao sac. This sac contributes to the formation of the 6 paired Ao arches

	==SELECTION OF AORTIC ARCHES==		=SELECTION OF AORTIC ARCHES=
	(Fig. 9)		(Fig. 9)
	* 1st Arch = Regresses except small portion - maxillary artery		* 1st Arch = Regresses except small portion - maxillary artery
Line 138:		Line 138:
	* R dorsal Ao regresses leaving the L dorsal Ao as the descending aorta		* R dorsal Ao regresses leaving the L dorsal Ao as the descending aorta

	==FORMATION OF THE VENOUS SYSTEM==		=FORMATION OF THE VENOUS SYSTEM=
	(Fig. 10)		(Fig. 10)
	* 3 pair of veins form the major veins in the embryo:		* 3 pair of veins form the major veins in the embryo:
Line 148:		Line 148:
	both sides of the liver.Both veins regresses except for L umbilical vein which becomes the ductus venosus		both sides of the liver.Both veins regresses except for L umbilical vein which becomes the ductus venosus

	==VENA CAVAE==		=VENA CAVAE=
	* Formed from the cardinal & subcardinal veins which together enlarge to form the hepatocardinal channel. After anastimosis w/ renal veins and regression of multiple branches, remaining		* Formed from the cardinal & subcardinal veins which together enlarge to form the hepatocardinal channel. After anastimosis w/ renal veins and regression of multiple branches, remaining
	portion = IVC		portion = IVC

WikiSysop at 10:13, 3 June 2025

2025-06-03T10:13:00Z

← Older revision		Revision as of 10:13, 3 June 2025
Line 26:		Line 26:
	* Mechanism of cardiac looping not well understood		* Mechanism of cardiac looping not well understood

	FORMATION OF THE EMBRYONIC VENTRICLES (Fig. 3)		==FORMATION OF THE EMBRYONIC VENTRICLES==
			(Fig. 3)
	truncus arteriosus		truncus arteriosus
	* After looping, the cardiac tube develops local expansions which are precursors to the cardiac chambers		* After looping, the cardiac tube develops local expansions which are precursors to the cardiac chambers
Line 38:		Line 39:
	* The primitive ventricle becomes trabeculated and forms the major portion of the LV. Both ventricular chambers dialate as CO increases		* The primitive ventricle becomes trabeculated and forms the major portion of the LV. Both ventricular chambers dialate as CO increases
	bulboventricular fange		bulboventricular fange
	DEVELOPMENT OF THE SINUS VENOSUS (Fig. 4)
			==DEVELOPMENT OF THE SINUS VENOSUS==
			(Fig. 4)
	* The sinus venous consists of three parts:		* The sinus venous consists of three parts:
	Central unpaired portion proximal to the atrium		Central unpaired portion proximal to the atrium
Line 50:		Line 53:
	common cardinal vein		common cardinal vein
	sinus horns		sinus horns
	FORMATION OF THE CARDIAC SEPTA
			==FORMATION OF THE CARDIAC SEPTA==
	umbilical vein		umbilical vein
	vilelline vein		vilelline vein
Line 71:		Line 75:
	cost. endocardial.		cost. endocardial.
	Cushion		Cushion
	THE ATRIOVENTRICULAR CANAL (Fig. 6)
			==THE ATRIOVENTRICULAR CANAL==
			(Fig. 6)
	* AV canal septation occurs by growth of the endocardial cushions. The anterior (superior) and posterior (inferior) AV cushion extend into the		* AV canal septation occurs by growth of the endocardial cushions. The anterior (superior) and posterior (inferior) AV cushion extend into the
	ant endocardial cushion		ant endocardial cushion
Line 78:		Line 84:
	Cushion L of septum primum = Ao leaflet of MV		Cushion L of septum primum = Ao leaflet of MV
	Cushion R of septum primum = septal leaflet of TV + crest of IVS		Cushion R of septum primum = septal leaflet of TV + crest of IVS
	MUSCULAR INTRAVENTRICULAR SEPTUM FORMATION (Fig. 7)
			==MUSCULAR INTRAVENTRICULAR SEPTUM FORMATION==
			(Fig. 7)
	* Muscular IVS formed by two processes:		* Muscular IVS formed by two processes:
	Medial walls of the expanding RV/LV oppose and fuse together		Medial walls of the expanding RV/LV oppose and fuse together
	Condensation of trabeculae in ventricular walls		Condensation of trabeculae in ventricular walls
	* Primary IV foramen between RV/LV never closes and forms LV outflow tract		* Primary IV foramen between RV/LV never closes and forms LV outflow tract
	CONOTRUNCAL SEPTATION (Fig. 8)
			==CONOTRUNCAL SEPTATION==
			(Fig. 8)
	* Truncus arteriosus of the embryonic heart is divided by conotruncal cushions		* Truncus arteriosus of the embryonic heart is divided by conotruncal cushions
	sentum primum		sentum primum
Line 94:		Line 104:
	* The IV foramen becomes reduced in size w/ completion of the conus septum by growth of tissue inferiorly from the septum which fuses w/ the inferior endocardial cushion to the top of the muscular septum		* The IV foramen becomes reduced in size w/ completion of the conus septum by growth of tissue inferiorly from the septum which fuses w/ the inferior endocardial cushion to the top of the muscular septum
	* The membranous IVS forms after completion of septation. Part of the EC cushion located between the septum primum & ventricular septum thins and forms the membranous septum		* The membranous IVS forms after completion of septation. Part of the EC cushion located between the septum primum & ventricular septum thins and forms the membranous septum
	FORMATION OF THE AV VALVES
			==FORMATION OF THE AV VALVES==
	* AV valves are derived from EC cushion, endothelium, and ventricular tissue.		* AV valves are derived from EC cushion, endothelium, and ventricular tissue.
	A skirt of ventricular tissue covered		A skirt of ventricular tissue covered
Line 101:		Line 112:
	* Mitral valve initially has 4 cusps; 2 of the cusps grow larger and their papillary muscles fuse in pairs to form anterior/posterior papillary muscles. The 2 smaller cusps become commissural cusps		* Mitral valve initially has 4 cusps; 2 of the cusps grow larger and their papillary muscles fuse in pairs to form anterior/posterior papillary muscles. The 2 smaller cusps become commissural cusps
	* Tricuspid valve forms from EC cushion, conus septum (= the conal papillary muscle + medial portion of the anterior cusp) and ventricular muscle		* Tricuspid valve forms from EC cushion, conus septum (= the conal papillary muscle + medial portion of the anterior cusp) and ventricular muscle
	FORMATION OF THE SEMILUNAR VALVES
			==FORMATION OF THE SEMILUNAR VALVES==
	* Semilunar valve form at the interface of the truncal cushions and the Ao/PA septum. Initially seen as paired tubercles in the septated truncus, a 3rd tubercle appears & by hollowing of the upper surface the Ao/PA valves form		* Semilunar valve form at the interface of the truncal cushions and the Ao/PA septum. Initially seen as paired tubercles in the septated truncus, a 3rd tubercle appears & by hollowing of the upper surface the Ao/PA valves form
	FORMATION OF THE ARTERIAL SYSTEM
			==FORMATION OF THE ARTERIAL SYSTEM==
	* Initial arterial system = blood islands that coalese to form vessels. Ist		* Initial arterial system = blood islands that coalese to form vessels. Ist
	major embryonic vessels = dorsal aortae which form along the axis of the		major embryonic vessels = dorsal aortae which form along the axis of the
Line 110:		Line 123:
	junction is the Ao sac. This sac contributes to the formation of the 6 paired Ao arches		junction is the Ao sac. This sac contributes to the formation of the 6 paired Ao arches

	SELECTION OF AORTIC ARCHES (Fig. 9)		==SELECTION OF AORTIC ARCHES==
			(Fig. 9)
	* 1st Arch = Regresses except small portion - maxillary artery		* 1st Arch = Regresses except small portion - maxillary artery
	* 2nd Arch = Regresses		* 2nd Arch = Regresses
Line 123:		Line 137:
	L distal portion persists as the ductus arteriosus		L distal portion persists as the ductus arteriosus
	* R dorsal Ao regresses leaving the L dorsal Ao as the descending aorta		* R dorsal Ao regresses leaving the L dorsal Ao as the descending aorta
	FORMATION OF THE VENOUS SYSTEM (Fig. 10)
			==FORMATION OF THE VENOUS SYSTEM==
			(Fig. 10)
	* 3 pair of veins form the major veins in the embryo:		* 3 pair of veins form the major veins in the embryo:
	Cardinal veins = drain the body of the embryo w/ the		Cardinal veins = drain the body of the embryo w/ the
Line 131:		Line 147:
	Unbilical veins = initially paired structures on both		Unbilical veins = initially paired structures on both
	both sides of the liver.Both veins regresses except for L umbilical vein which becomes the ductus venosus		both sides of the liver.Both veins regresses except for L umbilical vein which becomes the ductus venosus
	VENA CAVAE
			==VENA CAVAE==
	* Formed from the cardinal & subcardinal veins which together enlarge to form the hepatocardinal channel. After anastimosis w/ renal veins and regression of multiple branches, remaining		* Formed from the cardinal & subcardinal veins which together enlarge to form the hepatocardinal channel. After anastimosis w/ renal veins and regression of multiple branches, remaining
	portion = IVC		portion = IVC