Branching of Aorta 1 Flashcards
how in general does the aorta develop
from 6 aortic arches surrounding primitive pharynx in the fetus
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where does the aorta develop from
the left 4th aortic arch
where does the pulmonary trunk develop from
ventral parts of R & L 6th aortic arch
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where does the ductus arteriosus develop from
dorsal part of left 6th aortic arch
what occurs to the right 4th aortic arch
usually obliterated
if persists –> together with ligamentum arteriosum can rise to vascular ring obstruction of esophagus
where do the left and right coronary arteries arise from and what are their functions
aortic bulb –> ~15% of cardiac output
taking blood from the ventricles as it passes by and supplies the heart with oxygen rich blood
what view of the heart is this and identify the coronary arteries
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left lateral view
- pulmonary trunk
- left coronary artery
2’. paraconal interventricular branch
2’’. circumflex branch
- great cardiac vein (continued by coronary sinus on the right side of the heart)
3’. paraconal interventricular tributary of 3
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where does the right coronary artery run
right coronary artery: first superficial appearace towards cranial margin of heart, goes around the cranial margin onto the right side
where does the left coronary artery run
left coronary artery: makes external appearance and becomes superficial sending off branch that is going to caudal marigin and a branch travelling down to apex in the left ventricular groove supplies large area of the heart
where does the circumflex branch of the left coronary artery run
travels on coronary groove and onto the right hand side
what is the view of the heart and identify the coronary arteries
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- circumflex branch of left coronary artery
1’. right (subsinuosal) interventricular branch
- right coronary artery
2’. right (subsinuosal) interventricular branch
- coronary sinus
- great cardiac vein
- middle cardiac vein
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what are the species differences in L & R coronary arteries on right lateral view in ruminants, canines, equine and pig
ruminant & canine: left circumflex branch comes right around onto right side of heart and continues down to the interventricular groove and gives rise to subsinuosal branch on right side, the right coronary artery comes around on right side and peters out quickly –> larger area supplied by left coronary artery
equine & pigs: left coronary artery comes onto right side, the right coronary artery travels down to interventricular groove and gives rise to subsinuosal branch –> both right and left suppy equal amounts
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how does the aorta branch in the dog, cat, rabbit
after aorta leaves the base of the heart –> quickly gives rise to branches
- brachycephalic trunk (subdivides into the right subclavian. left common carotid a.)
- left subclavian artery
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how does the aorta branch in horse and cow
no independent left subclavian
large brachycephalic trunk giving rise to two common carotides and two subclavian vessels
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how does the aorta branch in the pig
common brachycephalic trunk and separate subclavian
differences in how brachycephalic gives rise to the branches compared to carnivore
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identify the branches of the aorta in the ventral aspect of the dog
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what do the L & R common carotid arteries supply
head and mid brain
where do the L & R common carotid arteries run
ventro-lateral surface of trachea (or esophagus left)
what are the L & R common carotid arteries a component of
ascend via the carotid sheath (vagosympathetic trunk and internal jugular vein)
the reccurent larygneal nerves travel alongside the carotid sheath but not inside it
how does the brachiocephalic trunk divide in the canine
immediately into 3 branches and mirrors how left subclavian is branching
- right subclavian artery
- left common carotid artery
- right common carotid artery
where does the descending aorta run
left of midline
how does the left subclavian artery arise
independent from brachiocephalic trunk
identify the branches of the external carotid artery
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describe how the common carotid artery branches in the dog
common carotid artery splits into two branches
- internal carotid artery: supplies the brain mostly
- external carotid artery: supplies the other structures of head
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what does the occipital artery supply
middle and internal ear
and meninges
what does the cranial laryngeal artery supply
supplies larynx
what does the ascending pharyngeal artery supply
pharynx
what does the lingual artery supply
tongue and palatine tonsil
what does the facial artery supply
lips
lateral nose
angle of mouth
what does the caudal auricular artery supply
external ear and associated muscles
what does the superficial temporal artery supply
masseter and upper and lower eyelids
what does the maxillary artery supply
branches into
- inferior alveolar
- external opthalmic
- ethmoidal
- palatine
- infraorbital
what can the facial arteries be used for
pulse for larger species
what can the superficial temporal arteries be used for
pulse transverse facial artery
horses
what are the branches of the internal carotid artery
enters cranial cavity (via guttural pouch in horses)
contributes to arterial circle of brain (horses and carnivores)
divides into divergent caudal and rostral branches
what does the vertebral artery supply
contributes to blood supply of brain along with internal carotid artery
gives rise to basalar artery which supplies brain
gow does the left subclavian artery branch
divides into 4 branches before curving around 1st rib
- vertebral artery
- internal thoracic artery
- superficial cervical artery
- costocervical artery
continues as axillary arteries which supply the forelimbs
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what do the right and left subclavian arteries supply
forelimbs and structures of neck and cervico-thoracic region
give off 4 main branches before curving around 1st rib
continues as the axillary arteries which supply the forelimbs
what does the left subclavian artery branch
winds around the cranial border of the 1st rib to enter the limb through the axilla to become the axillary artery
detaches 4 branches in ints intra-thoracic course
- vertebral artery
- costocervical artery
- superficial cervical artery
- internal thoracic artery
continues as left axillary artery
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where does the left vertebral artery run
cranio-dorsally via transverse foramina to enter vertebral canal within the atlas
what does the left vertebral artery form
basilar artery (brain) and the ventral spinal artery (spinal chord)
what does the brachiocephalic trunk give rise to
L/R common carotid arteries
right subclavian artery
what does the left costocervical artery form
1st few dorsal intercostal arteries and deep cervical artery (dorsal cervical muscles of the neck)
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what does the left superficial cervical artery supply
supplies ventral neck muscles, cranial shoulder and upper forelimb
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where does the left internal thoracic artery pass
between sternum and transversus thoracis muscle
what does the left internal thoracic artery form
ventral intercostal arteries/musculo-phrenic artery
how does the left internal thoracic artery enter the abdomen
tunnels beneath diaphragm into abdomen
what does the left internal thoracic artery form in the abdomen
cranial superficial/deep epigastric arteries
what does left axillary artery supply
lateral chest wall and forelimb
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what does the left axillary artery branch into
external and lateral arteries
branchial artery
median artery
how does the right subclavian artery
- r. vertebral artery
- r. costocervical artery
- r. internal thoracic artery
- r. superficial cervical artery
- r. axillary artery
- right brachial artery
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how does the thoracic aorta branch in the dog
- 1st few intercostal arteries derived from costocervical artery
- 4th and 5th inter-costal arteries arise from the descending thoracic aorta –> supply vertebral column and intercostal structures
- bronchesophageal arteries arise approx 5th intercostal arteries –> supply bronchi and esophagus
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where does the position at which the aorta penetrates the diaphragm
- aortic hiatis: contains aorta, thoracic duct, azygous vein
left to midline
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