sabato 16 marzo 2019
Cardiosplanchnology
Major Arteries
The ascending aorta originates from the left ventricle. The arch of aorta, the only part of the aorta in the
superior mediastinum, and begins when the ascending aorta emerges from the pericardial sac. It ends on
the left side at the level of TIV/TV. The arch is initially anterior and finally lateral to the trachea. Three
branches arise from the superior border of the arch, all three crossed anteriorly by the left brachiocephalic
vein.
The first branch of the aorta is the brachiocephalic trunk, which is the largest and originates behind the
manubrium of the sternum, slightly anterior to the other two branches. It slightly ascends posteriorly and to
the right. At the level of the right sterno-clavicular joint in divides into the right common carotid artery ad
the right subclavian vein. These mainly supply the right side of head and neck, and the right upper limb
respectively. Sometimes the brachiocephalic trunk has a small branch, the thyroid ima artery,
contributing to the supply of thyroid gland.
The second branch of the aorta is the left
common carotid artery, arising to the left and
slightly anteriorly to the brachiochephalic trunk.
It ascends through the superior mediastinum
along the left side of the trachea. It supplies the
left side of head and neck.
The third branch is the left subclavian artery,
arising immediately to the left and slightly
posteriorly to the left common carotid artery. It
ascends through the superior mediastinum
along the left side of the trachea. It supplies
blood to the left upper limb.
The ligamentum arteriosum is a remnant of
the ductus arteriosus, which during embryonic
circulation connects the pulmonary trunk to the
arch of aorta, allowing the bypass of the lungs.
It closes soon after birth.
SUBCLAVIAN ARTERY
The subclavian artery exits the thorax via the superior thoracic aperture between the anterior and middle
scalene muscles and passes between the first rib and clavicle. It can be divided into three parts.
The first part goes from its origin to the medial border of scalenus anterior. In this part it branches into:
• Vertebral artery, which courses cranially to supply the posterior fossa and occipital lobes, as well as
provide segmental vertebral and spinal column blood supply. The posterior inferior cerebellar artery
(PICA) is its largest branch and is one of three main arteries supplying the cerebellum.
• Internal thoracic artery, previously known as internal mammary artery courses caudally.
• Thyrocervical trunk, very short, it soon divides into 4 branches
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, sabato 16 marzo 2019
The second part is posterior to scalenus anterior. In
this part it branches into:
• Costocervical trunk, which courses cranially
before bifurcating.
• Dorsal scapular artery, which courses posteriorly
and might also arise from the thyrocervical trunk.
The third part goes from the lateral border of
scalenus anterior to the lateral border of the first rib,
where it becomes the axillary artery.
The thyrocervical trunk gives rise to four branches:
• The inferior thyroid artery is the largest branch
and ascends medial and posterior to the lower pole
of the thyroid gland. It sends multiple small branches through the pretracheal fascia to supply the larynx,
trachea, esophagus, and thyroid and parathyroid glands, as well as adjacent muscles, hence is the
primary visceral artery of the neck.
• The ascending cervical artery is a small artery that ascends medial to the phrenic nerve on the
prevertebral fascia. It contributes many small spinal branches into the intervertebral foramina of the neck
and small muscular branches to the lateral muscles of the upper neck.
• The transverse cervical artery is a short artery that further bifurcates into the superficial and deep
branches, that course superficially and laterally across the phrenic nerve and anterior scalene muscle.
They then cross the trunks of the brachial plexus, supplying branches to their vasa nervorum. Its
2
, sabato 16 marzo 2019
branches are:
- The superficial branch passes anterior to the trapezius muscle.
- The deep branch travels down the scapula and turns into the dorsal scapular artery, contributing to
the scapular arterial anastomoses and supplying levator scapulae and rhomboid muscles. It may arise
directly from the third or the second part of the subclavian artery.
• The suprascapular artery travels inferiorly and laterally superficial to the anterior scalene muscle
before crossing the third part of the subclavian artery. It then courses posterior to the clavicle to supply
the posterior scapular muscles. It may arise directly from the third part of the subclavian artery.
The internal thoracic artery passes from the neck to the thorax posterior to the first rib. Along its course,
it gives off:
• Perforating cutaneous branches which supply the skin. At the 2nd-to-4th intercostal spaces these
perforating branches are larger to supply the breasts.
• Anterior intercostal arteries that branch within each intercostal space.
• Pericardiophrenic artery, which runs with the phrenic nerve and supplies pericardium and diaphragm.
3
Cardiosplanchnology
Major Arteries
The ascending aorta originates from the left ventricle. The arch of aorta, the only part of the aorta in the
superior mediastinum, and begins when the ascending aorta emerges from the pericardial sac. It ends on
the left side at the level of TIV/TV. The arch is initially anterior and finally lateral to the trachea. Three
branches arise from the superior border of the arch, all three crossed anteriorly by the left brachiocephalic
vein.
The first branch of the aorta is the brachiocephalic trunk, which is the largest and originates behind the
manubrium of the sternum, slightly anterior to the other two branches. It slightly ascends posteriorly and to
the right. At the level of the right sterno-clavicular joint in divides into the right common carotid artery ad
the right subclavian vein. These mainly supply the right side of head and neck, and the right upper limb
respectively. Sometimes the brachiocephalic trunk has a small branch, the thyroid ima artery,
contributing to the supply of thyroid gland.
The second branch of the aorta is the left
common carotid artery, arising to the left and
slightly anteriorly to the brachiochephalic trunk.
It ascends through the superior mediastinum
along the left side of the trachea. It supplies the
left side of head and neck.
The third branch is the left subclavian artery,
arising immediately to the left and slightly
posteriorly to the left common carotid artery. It
ascends through the superior mediastinum
along the left side of the trachea. It supplies
blood to the left upper limb.
The ligamentum arteriosum is a remnant of
the ductus arteriosus, which during embryonic
circulation connects the pulmonary trunk to the
arch of aorta, allowing the bypass of the lungs.
It closes soon after birth.
SUBCLAVIAN ARTERY
The subclavian artery exits the thorax via the superior thoracic aperture between the anterior and middle
scalene muscles and passes between the first rib and clavicle. It can be divided into three parts.
The first part goes from its origin to the medial border of scalenus anterior. In this part it branches into:
• Vertebral artery, which courses cranially to supply the posterior fossa and occipital lobes, as well as
provide segmental vertebral and spinal column blood supply. The posterior inferior cerebellar artery
(PICA) is its largest branch and is one of three main arteries supplying the cerebellum.
• Internal thoracic artery, previously known as internal mammary artery courses caudally.
• Thyrocervical trunk, very short, it soon divides into 4 branches
1
, sabato 16 marzo 2019
The second part is posterior to scalenus anterior. In
this part it branches into:
• Costocervical trunk, which courses cranially
before bifurcating.
• Dorsal scapular artery, which courses posteriorly
and might also arise from the thyrocervical trunk.
The third part goes from the lateral border of
scalenus anterior to the lateral border of the first rib,
where it becomes the axillary artery.
The thyrocervical trunk gives rise to four branches:
• The inferior thyroid artery is the largest branch
and ascends medial and posterior to the lower pole
of the thyroid gland. It sends multiple small branches through the pretracheal fascia to supply the larynx,
trachea, esophagus, and thyroid and parathyroid glands, as well as adjacent muscles, hence is the
primary visceral artery of the neck.
• The ascending cervical artery is a small artery that ascends medial to the phrenic nerve on the
prevertebral fascia. It contributes many small spinal branches into the intervertebral foramina of the neck
and small muscular branches to the lateral muscles of the upper neck.
• The transverse cervical artery is a short artery that further bifurcates into the superficial and deep
branches, that course superficially and laterally across the phrenic nerve and anterior scalene muscle.
They then cross the trunks of the brachial plexus, supplying branches to their vasa nervorum. Its
2
, sabato 16 marzo 2019
branches are:
- The superficial branch passes anterior to the trapezius muscle.
- The deep branch travels down the scapula and turns into the dorsal scapular artery, contributing to
the scapular arterial anastomoses and supplying levator scapulae and rhomboid muscles. It may arise
directly from the third or the second part of the subclavian artery.
• The suprascapular artery travels inferiorly and laterally superficial to the anterior scalene muscle
before crossing the third part of the subclavian artery. It then courses posterior to the clavicle to supply
the posterior scapular muscles. It may arise directly from the third part of the subclavian artery.
The internal thoracic artery passes from the neck to the thorax posterior to the first rib. Along its course,
it gives off:
• Perforating cutaneous branches which supply the skin. At the 2nd-to-4th intercostal spaces these
perforating branches are larger to supply the breasts.
• Anterior intercostal arteries that branch within each intercostal space.
• Pericardiophrenic artery, which runs with the phrenic nerve and supplies pericardium and diaphragm.
3
