Arteries of the trunk Flashcards
A. thoracica interna
- arises from the lower side of a. subclavia
- descends along the anterior internal surface of thoracic cavity
- behind the cartilages of the upper six ribs in the distance of about 1,5 cm from the border of the sternum.
- at the level of costae 7 the divides into two terminal branches:
- arteria epigastrica superior:
- penetrates diaphragm
- at the level of the umbilical ring it communicates with arteria epigastrica inferior from arteria iliaca externa
- supplies musculus rectus abdominis. - arteria musculophrenica:
- makes its way obliquely downward and laterally, supplies the diaphragm and the lower intercostal spaces (rami intercostals anteriores)
Side branches:
1. rr. intercostales anteriores supply the upper intercostal spaces and communicate with arteria intercostales posteriores from aorta thoracica for female – branches to the mammary gland
- a. pericardiacophrenica - supplies the mediastinal part of the pleura, the pericardium, the diaphragm;
- rr. bronchiales - supply the lower part of the trachea and the main bronchi;
- rami thymici – supply thymus;
- rami sternales – supply sternum;
- rami mediastinales – supply pleura mediastinalis
Blood circulation
circulus sanguinis minor / pulmonary circulation
- deoxygenated blood from ventriclus dexter is pumped into truncus pulmonalis and then via a. pulmonalis dextra et sinistra into the capillary networks of the lungs. From the lungs oxygenated blood flows back via venae pulmonales (4) into atrium sinistra
Truncus pulmonalis starts from ventriculus dexter behind art. sternoclavicularis sinistra.
x on the right side and behind – aorta ascendens
x on the left side – auricula sinistra
x below aortic arch it divides into artery pulmonalis dextra et sinistra
–> Arteria pulmonalis dextra runs to the right side behind aorta ascendens and vena cava superior to hilum pulmonis, where it divides into lobar and segmental arteries.
–> formed by the capillaries and venules of the lungs. Venae pulmonales leave the lung via hilum pulmonis.
Circulus sanguinis major/The systemic circulation:
- supplies blood to all the organs
- The oxygenated blood from ventriclus sinister is pumped into aorta and then via arteries into the capillary networks of the organs
- The deoxygenated blood is returned into the atrium dexter from the lower limbs and the lower part of the trunk via vena cava inferior and from the head and neck, the upper limbs and the upper part of the trunk via vena cava superior.
Aorta
- the main trunk of arterial vessels
- Aorta ascendes - behind truncus pulmonalis to the right
- Arcus aortae - backward and to the left
- Aorta descendes - T4 and divides into:
a. aorta thoracica- lies to the left of the column
- -> crosses oesophagus
- -> passes through hiatus aorticus diaphragm
b. aorta abdominalis - in front of vertebral column
- -> at L4 divides into a. iliac communes dextra et sinistra
- -> continuation “remnant”: a. sacralis mediana
Aorta ascendes
- about 5 cm in lenght.
- originates by ostium aortae at the upper part of ventriculus sinister at the level of costae sinister 3 behind sternum.
- dilatation bulbus aortae at the
origin place; formed by three sinus aortae. - curves obliquely upward, anteriorly and to the right as high as the upper border of cartilagines costales dexter 2 –> continues into arcus aortae.
- surrounded by pericardium.
At the level of sinus aortae, aorta ascendens has two side branches:
- a. coronaria dextra
- et sinistra
Arteria coronaria dextra
- > passes to the right from above sinus aorta and lies in sulcus coronarius
- > curves around margo dexter to facies diaphragmatica
- > passes from the right side to the left
- > descends along sulcus interventricularis posterior as ramus interventricularis posterior to the apex
- At apex cordis makes anasthomoses with r. interventricularis anterior from a. coronaria cordis sinistra
- At the coronary groove makes anasthomosis with r. circumflexus from a. coronaria cordis sinistra.
supplies:
- the right atrium and septum interatriale
- the posterior wall and part of the anterior wall of ventriculus dexter
- the posterior third of septum interventriculare
- mm. papillares of ventriculus dexter, m. papillaris posterior of ventriculus sinister
- part of the posterior wall of ventriculus sinister
- nodus sinuatrialis, nodus atrioventricularis.
Arteria coronaria sinistra
- from arcus aortae at sinus aortae level
- divides into two branches:
- r. interventricularis anterior:
- descends along sulcus interventricularis anterior to apex cordis –> communicates with r. interventricularis posterior from a. coronaria dextra - r. circumflexus:
- runs along sulcus coronarius at first to the left around facies pulmonalis
- then to the right as far as sulcus interventricularis posterior and communicates with a. coronaria dextra
Because of anastomoses of both coronary arteries there are two arterial circles – horizontal one along sulcus coronarius and oblique one along sulcus interventricularis anterior et posterior.
A. coronaria sinistra supplies:
- atrium sinistrum
- ventriculus sinister (except a small part of the posterior wall)
- part of the anterior wall of ventriculus dexter
- the two anterior thirds of septum interventriculare
- m. papillaris anterior of ventriculus sinister
- fasciculus atrioventricularis
Vv. cordis
The veins of the heart (vv. cordis) drain blood directly into the hearts cavities. To them belong:
- sinus coronaries
- The venous blood of the heart by veins of the heart is drained into it
- lies in posterior part of the heart in sulcus coronarius and terminates in the right atrium by ostium sinus coronarii.
- it receives 5 tributaries:
- V. cardiaca magna –
- Corresponds to the supply area of a. coronaria sinistra
- > begins at apex cordis,
- > ascends along sulcus interventricularis anterior
- > curves to the left around facies pulmonalis cordis
- > lies in sulcus coronarius and ends in there
- V. cardiaca media
- commences at apex cordis, ascends along sulcus interventricularis posterior, opens into the sinus coronarius
- V. cardiaca parva
- runs along sulcus coronarius between the right atrium and right ventricle, curves around margo dexter cordis and opens into the sinus coronarius
- V. ventriculi sinistri posterior
- drains the venous blood from the left ventricle and ends in the sinus coronarius
- V. obliqua atrii sinistri
- drains the venous blood from the left atrium, opens into the sinus coronaries
- vv. cardiac (cordis) anteriores
- “transmural system”
- located on facies sternocostalis
- drain the venous blood from right ventricle anterior wall and open directly into the right atrium by means of small orifices. - vv. cardiaca (cordis) minimae
- “endomural system”
- numerous, they arise in the wall/all parts of the heart
- open mainly into the right atrium by foramina venarum minimarum, but could open also into the ventricle.
Cardiac innervation
Cardiac innervation is provided by two autonomus, interconnected plexuses:
- Plexus cardiacus superficialis – located between arcus aotae concave and truncus pulmonalis
- Plexus cardiacus profundus – located between the posterior surface of arcus aortae and bifurcatio tracheae
Vegetative/autonomic fibers spreads along the arteriae coronariae.
N. vagus (parasympathetic pregg and sensory neurons) with branches:
- rr. cardiaci cervicales superiores (from pars cervicalis n. vagi)
- rr. cardiaci cervicales inferiores (from n. laryngeus recurrens)
- rr. cardiaci thoracici (from pars thoracica n. vagi)
Postgg parasympathetic neurons (ganglia intramuralia) in the atrial walls, septum interatriale and along arteriae coronariae.
Sympathetic innervation provides two types of neurons:
- pregg sympathetic neurons (perikaryon - nucleus intermediolateralis) T1-5
- post-ganglionic sympathetic neurons (perikaryon – ganglia trunci sympathici cervicales 1-3, ganglia trunci sympathici thoracici 1-5).
o Truncus sympathicus axons or branches:
- n. cardiacus medius (from ganglion medium)
- n. cardiacus cervicalis inferior (from ganglion inferius)
- rr. cardiaci thoracici (from I – V ganglia thoracica)
Cardiovascular clinical names:
- RCA - a. coronaria cordis dextra
- PDA - r. interventricularis posterior
- LCA - a. coronaria cordis sinistra
- LMCT - left main trunk common
- RSS - ramus anterior interventricularis
- CX - r. circumflexes
Arcus aortae
Arcus aortae is the continuation of aorta ascendens. It begins at the level of the art. sternocostalis dexter 2, runs upward, backward and to the left, then passes downward and at the level of T4
becomes continuation of aorta descendens.
- anteriorly – thymus (for children) or remnants of thymus (for adults)
- posteriorly – bifurcatio tracheae
- superiorly – v. brachiocephalica sinistra
- inferiorly – truncus pulmonalis division into a. pulmonalis dextra et sinistra
From the lower surface of arcus aorticus arise small branches for supplying adjacent organs:
- rr. tracheales
- rr. bronchiales
From the upper surface of arcus aortae start three blood vessels:
- truncus brachiocephalicus
- truncus brachiocephalicus is the largest branch of arcus aortae, it has lenght about 2-3 cm
- the trunk ascends obliquely upward, backward and to the right
- at the level of art. sternoclavicularis dexter it divides into:
i. a. carotis communis dextra
ii. a. subclavia dextra. - a. carotis communis sinistra
- a. subclavia sinistra
Aorta thoracica
passes in mediastinum posterius. It begins at the lower border of T4 and extends to the lower border of T12 at hiatus aorticus. At the commencement aorta thoracica is situated to the left from columna vertebralis, then it approaches to the median line.
- at its termination aorta thoracica lies directly in front of columna vertebralis
- at the level of T8 – T9 aorta thoracica is crossed by esophagus
- to the left from it lies pleura costalis
- to the right – v. azygos, ductus thoracicus
The side branches of aorta thoracica are divided into two groups – visceral and parietal.
Visceral branches:
- rr. bronchiales:
- contents of radix pulmonis
- supply the lungs, bronchi and pleura visceralis - rr. oesophageales
- supply the esophagus
- upper branches communicate with rr. oesophagales of a. thyroidea inferior that supply cervical part of the oesophagus
- lower branches communicate with rr. oesophageales from a. gastrica sinistra
- supply abdominal part of the esophagus - rr. pericardiaci
- supply the posterior surface of pericardium
- communicate with branches of a. pericardiacophrenica - Rr. mediastinales
- numerous vessels for supplying the lymphatic nodes, fibrous and fatty tissue in
mediastinum posterius.
Parietal branches:
- aa. phrenicae superiores
- supply the diaphragm and its coverings - aa. intercostales posteriores
- ten paires of those arteries
- absent in spatium intercostale 1 et 2
(muscles of those spaces are supplied by a. intercostalis suprema from truncus costocervicalis)
- the last a. intercostale posterior passes below costae duodecima and is called a. subcostalis
- each a. intecostales runs along the lower margin of the rib, lies in sulcus costae with v. intercostalis posterior above and n. intercostalis below it
- gives off side branches:
** r. dorsalis
» arises at the level of collum radii, runs backward
» supplies deep muscles and skin of the back
» from this branch starts r. spinalis
> passes through foramen interverterbale to supply the spinal cord and the coverings
** r. collateralis
» originates near angulus costae, approaches the upper border of the rib below
» supplies muscles and skin
» r. collateralis and a. intercostalis posterior communicate with rr. intercostales anteriores from a. musculophrenica from a. thoracica interna
** r. cutaneus lateralis
» supply skin of the lateral and anterior parts of the trunk
** rr. mammarii laterales (for female) arise from aa. intercostale posteriores 4 - 6 to supply glandula mammae
- Aa. intercostales posteriores supply:
- mm. thoracici profundi
- mm. dorsi profundi
- mm. abdominalis regio epigastrici et mesogastrici
- pleura
- skin of the trunk (anterior and lateral parts)
- the adjacent bones
- the spinal cord and its coverings
glandula mammae for female
Aorta abdominalis
- Starts from hiatus aorticus diaphragmae until L4
Topographia:
Holotopia
- regio epigastrica
- region umbilicalis
Skeletotopia
- From T12 – L4
Syntopia
- located retroperitoneally
- descends along columna vertebralis left to
the midline
Posteriorly: - columna vertebralis Right side: - v. cava inferior Anteriorly: - corpus pancreatis - pars ascendens duodeni - radix mesenterii Left side: - truncus sympaticus
Visceral branches are divided into two groups – the unpaired and paired branches.
Unpaired visceral branches of aorta abdominalis: 3
1. truncus coeliacus
2. a. mesenterica superior
3. a. mesenterica inferior
Paired visceral branches of aorta abdominalis: 4
- a. suprarenalis media
- a. renalis
- a. testicularis
- a. ovarica
–> so 7 visceral Branches!
Parietal branches: 2
- aa. phrenicae inferiores
- aa. lumbales
truncus coeliacus
just below hiatus aorticus diaphragmae (Th12), is about 1-3cm long; divides into 3 arteries:
- a. gastrica sinistra
- rr. Gastici descends along curvatura minor of gaster supplying it
- rr. oesophagealis supplies pars abdominalis oesophagei
- a. gastrica sinistra communicates with a. gastrica dextra (from a. hepatica communis) - a. splenica s. a. lienalis
- runs left behind gaster along the upper border of pancreas
- It terminates at hilum splenicum –> rr. splenici, supplies splen s. lien
- Side branches:
* * rr. pancreatici – supply corpus et cauda pancreatis
* * aa. gastricae breves – supply fundus gastricae
* * a. gastroomentalis sinistra s. gastroepiploica sinistra – descends along curvatura major of gaster
- -> communicates with a. gastroomentalis dextra s. a. gastroepiploica dextra (from a. gastroduodenalis)
- -> rr. gastrici supply gaster
- -> rr. epiploici supply omentum majus - a. hepatica communis
- Runs to the liver and gives one side branch (a. gastrica dextra), and 2 terminal arteries (a. hepatica propria and a. gastroduodenalis)
- a. gastrica dextra
- passes along curvatura minor of gaster
- communicates with a. gastrica sinistra (from truncus coeliacus)
- rr. gastici supply gaster
Terminal branches:
- a. hepatica propria
- passes together with ductus choledochus and v. portae hepatis in lig. Hepatoduodenale
- R. dexter et sinister supply hepar
- R. dexter gives a. cystica to vesica biliaris
** a. gastroduodenalis
- divides to 2 branches:
> a. gastroomentalis dextra s. a. gastroepiploica dextra
o ascends along curvatura major of gaster
o communicates with a. gastroomentalis sinistra s. gastroepiploica sinistra (from a. splenica s. a. lienalis)
- rr. gastrici supply gaster
- rr. epiploici supply omentum majus
> a. pancreaticoduodenalis superiores
o lies between duodenum and caput pancreatis supplying them
o communicates with a. pancreaticoduodenalis inferior (from a. mesenterica superior)
A. mesenterica superior
- Arises from aorta abdominalis at L1
- Goes between caput pancreatis et pars ascendens duodeni
- descends between the layers of radix mesenterii and terminates as a. ileocolica to supply caecum and terminal part of ileum
- a. ileocolica gives of small branch:
o a. appendicularis to appendix vermiformis - a. iliacus
- a. colicus
Side branches of a. mesenterica superior:
- aa. jejunales et aa. Ileales
- Supply jejunum and ileum
- They run between the layers of the mesentery and there are numerous anastomotic arches between them (12-18) - a. pancreaticoduodenalis inferior
- goes upward and supplies duodenum and caput pancreatis
- communicates with aa. pancreaticoduodenalis superiores (from a. gastroduodenalis) - a. colica dextra – supplies colon ascendens
- R. descendens
- > Follow colon ascendens and makes anastomosis with a. iliocolica
- R. ascendens
- > Anastomosis with a. colica media - a. colica media – supplies proximal 2/3 of colon transversum
- R. dexter
- -> Anastomosis with a. colica dextra
- R. sinister
- -> Anastomosis with a. colica sinistra : called ”anastomosis magna s. arcus marginalis coli”
Communication between branches of a. mesenterica superior et inferior is called arcus marginalis coli / anastomoses magna
» It is formed by r. sinister of a. colica media (a. mesenterica superior) and r. ascendens of a. colica sinistra (a. mesenterica inferior).
A. mesenterica inferior
- arises from aorta abdominalis at L3
- descends into the cavitas pelvis
- terminates as a. rectalis superior, which supplies the upper third of rectum
- gives 2 side branches:
- a. colica sinistra
- supplies colon descendens and regio flexurae lienalis coli transversi
* R. descendens
- -> anastomosis with aa. Sigmoidee
* R. ascendens
- -> Anastomosis with r. sinister of a. colica media
- Participates in formation of arcus marginalis coli - aa. sigmoideae
- run between layers of mesocolon sigmoideum and supplies colon sigmoideum
- Aa. sigmoideae superiores have anastomosis with r. descendens from a. colica sinistra
- Aa. sigmoideae inferiores have anastomosis with a. rectalis superior
a. suprarenalis media
x arise from aorta abdominalis at L1 x supplies glandula suprarenalis x glandulae suprarenales recieve additionally blood supply from o a. suprarenalis superior branch of a. phrenica inferior o a. suprarenalis inferior branch of a. renalis
a. renalis
- arises from aorta abdominalis at L2
- supplies ren
- rr. ureterici supply upper 1/3 of the ureter
- gives a side branch:
–> a. suprarenalis inferior
supply glandula suprarenalis
a. testicularis
- arises from aorta abdominalis at L2 or L3 and runs retroperitoneally on the posterior
abdominal wall, crosses ureter - It passes through canalis inguinalis, is a component of funiculus spermaticus
- supplies testis and epididymis
- rr. ureterici supply the middle 1/3 of ureter
a. ovarica
- arises from aorta abdominalis at L2 or L3 and runs retroperitoneally along the posterior abdominal wall, crosses ureter
- goes laterally and crosses linea terminalis
- In pelvis major artery goes within lig. suspensorium ovarii thus reaching hilum ovarii
- anastomoses with r. ovaricus (from a. uterina) and supplies the ovary
- Rr. ureterici supply the middle 1/3 of ureter
- Rr. tubarii supply tuba uterina
aa. phrenicae inferiores
- arises from aorta abdominalis at Th12
- supplies the lower surface of the diaphragm
- gives off aa. suprarenales superiores to glandula suprarenalis
aa. lumbales
- 4 pairs: each artery gives off r. ventralis et dorsalis
- R. ventalis supplies mm. abdominalis posteriores et laterales including the abdominal wall
- R. dorsalis supply mm. profundi dorsi and cutis on the appointed region
–> Gives off r. spinalis which goes through foramen intervertebrale entering canalis
spinalis
–> Supplying meninges and medulla spinalis
A. iliaca communis
Aorta abdominalis terminates at bifurcation aortae and divides into a. iliaca communis dextra et sinistra.
Topographia:
Holotopia
- region umbilicalis
Skeletotopia
- From L4 to art. sacroiliaca dx. et sin
Syntopia
- A. iliaca communis dx. et sin. are only about 5 cm in long arteries
- Run along medial border of m. psoas major
Anteriorly - ureter Laterally - m. psoas major Posteriorly - V. iliaca communis
Terminal branches:
- A. iliaca externa et interna
- Gives off rr. ureterici for blood supply to pars distalis ureter
A. Iliacae Externaea
Topographia:
Skeletotopia
- From art. sacroiliaca a. iliaca externa descends to linea terminalis along medial border of m. psoas major
- Leaves pelvis by continueing to lacuna vasorum
- After leaving lacuna vasorum continues as a. femoralis
Syntopia
- proximally a. iliaca externa is facing v. iliaca externa anteriorly, but distally v. iliaca externa is laterally
- Gives off two main side branches:
1. A. epigastrica inferior - ascends obliquely between layers of vagina m. recti abdominis and supplies muscles of the anterior wall of the abdominal cavity
- Runs within plica umbilicalis lateralis anastomosis with a. epigastrica superior
- Supply anterior wall of mm. abdominalis
Gives off side branches:
a. r. pubicus
- -> Goes along ramus superior ossis pubis
- -> Anastomosis (”corona mortis”) with r. pubicus from a. obturatioria
b. A. cremasterica (male)
–> goes to canalis inguinalis
Supplies:
* m. cremasterica
* coverings of funiculus spermaticus
c. A. ligamenti teretis uteri
- -> Goes to canalis inguinalis
- -> Supplies lig. teres uteri
- A. circumflexa ilium profunda
- passes along lig. inguinale et crista iliaca
- communicates with r. iliacus from a. iliolumbalis
- Supply mm. abdominalis and mm. cinguli membri inferioris
A. Iliacae Internae
Topographia
Skeletotopia
- From art. sacroiliaca descends down crossing linea terminalis and arriving to pelvis minor.
- Runs along paries lateralis pelvis minoris at the level of foramen ischiadicum major where branchers further.
- Side branches are divided into visceral (for organs) and parietal (for muscles) branches
Visceral branches:
- A. umbilicalis
- Aa. vesicalis inferiores - Supply fundus vesica urinaria, prostata (male), anterior wall of vagina (female)
- A. ductus deferentis / A. uterina
- A. rectalis media - Supply middle 1/3 of rectum
- A. pudenda interna
Parietal branches:
- A. iliolumbalis
- Aa. sacrales laterales
- A. obturaoria
- A. glutea superior
- A. glutea inferior
A. umbilicalis
- Ascends along the anterior wall of cavitas abdominalis to anulus umbilicalis
- A. umbilicalis runs prenatally in plica umbilicalis medialis
Side branches:
- Aa. vesicales superiores
- Supply apex et corpus vesica urinaria
A. ductus deferentis / A. uterina
Male:
- Accompanies ductus deferens
- Supply ductus deferens, vesiculae seminales and lower 1/3 of ureter
Female:
- Runs along the lateral wall of cavitas pelvis
- turns medially, passes along lig. cardinale uteri s. lig. transversum cervicis to cervix uteri
- ascends along lateral side of uterus
- Supply uterus
Gives off branches:
- r. tubarius – supply tubae uterinae
- r. ovaricus – directs to ovarium along lig. latum uteri, anastomoses with a. ovarica
- r. vaginales – supply vagina
A. pudenda interna
- Leaves cavitas pelvis through foramen ischiadicum majus via foramen infrapiriforme
- Terminates at organa genitalia externa and supply them
o A. dorsalis penis
o A. dorsalis clitoridis
o A. profunda penis
o A. profunda clitoridis
o Rr. scrotales posteriors
o Rr. labiales posteriors - side branches:
1. A. rectalis inferior: supply lower 1/3 of rectum
2. A. perinealis: supply muscles of the perineum
Gives off:
x Rr. scrotales posteriores
x Rr. labiales posteriores
- A. urethralis: supply urethra
- A. bulbi penis / A. bulbi vestibule
supply genitalia externa
A. iliolumbalis
- Ascends and crosses linea terminalis in cavitas pelivis, enterns pelvis major
- Supply muscles of the posterior and anterior wall of cavitas abdominalis
Gives off:
- R. ilicus
- Anastomosis with a. circumflexa ilium profunda (from a. iliaca externa) - R. lumbalis
Aa. sacrales laterales
- Descends along facies pelvina ossis sacri
- Supply mm. cinguli membri inferioris and the perineum
A. obturaoria
- Supply medial group of mm. membri inferioris liberi and m. obturatorius externus
Gives off:
- r. acetabularis
- Runs as lig. capitis femoris inside art. coxae
- Supply caput femoris - r. pubicus
A. glutea superior
- Leaves cavitas pelvis through foramen ischiadicum majus via foramen suprapiriforme
Supply: o M. gluteus minimus o M. gluteus medius o M. tensor fasciae latae o Art. Coxae
A. glutea inferior
- Emerges through foramen ischiadicum majus via foramen infrapiriforme
Supply: o M. gluteus maximus o M. piriformis o M. obturatorius internus o Mm. gemelli (= m. gemellus superior et inferior) o M. quadratus femoris
Venous system
The blood flow in veins is from the periphery to the center. Veins of the systemic circulation could be
divided into four systems due their fusion:
- veins of the heart, which terminate directly into the right atrium
- cava superior system joins the veins of the head, neck, upper limb and thorax, which terminate into v. cava superior
- cava inferior system joins the veins of the lower limb, abdomen and pelvis, which
terminate into v. cava inferior - portal system contains v. portae hepatis
V. brachiocephalica
- drains the head, neck and upper limb
- formed by union of v. jugularis interna and v. subclavia behind art. sternoclavicularis
- 3 cm
- commences at the level of art. sternoclavicularis dx.
» descends straight downward to costae prima and joins the v. brachiocephalica sinister
V. brachiocephalica sinistra:
- twice longer (about 6 cm long)
- oblique course behind manubrium sterni.
crosses:
- n. phrenicus sinister
- n. vagus sinister
- a. subclavia sinister
- a. carotis communis sinister
- trachea
- truncus brachiocephalicus
tributaries:
1. V. thyroidea inferior
- V. vertebralis
- V. cervicalis profunda - starts from plexus venosus vertebralis externus and drains the occipital region
- Vv. thoracicae internae- drains the same parts of the body as artery supplies
- V. intercostalis suprema dextra et sinistra - drains the upper 1 – 2 spatium intercostale
- V. intercostalis superior sinistra - drains the upper 3 – 4 spatium intercostale of left side
V. thyroidea inferior
- drains plexus thyreoideus impar, which lies in the lower part of glandula thyroidea
- anastomoses with plexus thyroideus
- plexus thyroideus impar drains the adjacent organs: larynx, trachea (the upper parts), oesophagus and thymus
V. cava superior
- drains the upper part of the trunk above the diaphragm
- formed by union of v. brachiocephalica dextra et sinistra behind synchondrosis costae primae dextra
- lies in mediastinum superius
- runs from cartilagines costae prima to cartilagines costae 3
- Lower part is within the pericardium
Left
* aorta
right
- pars mediastinalis pleurae parietalis
- n. phrenicus
- vasa pericardiacophrenica
posteriorly
- bronchus principalis dexter
- a. pulmonalis dexter
- vv. pulmonales dexter
anteriorly
* thymus
- It has only one tributary – vena azygos
