9. Heart & Vascular System (Part 2)

Question 1

What is the first vessel to branch off the aorta?

Answer 1

Coronary arteries

Question 2

At what height does the arch of aorta begin and end?

Answer 2

2nd sternocostal joint

Question 3

Describe the relative position of the aortic arch as it ascends and descends.

Answer 3

• The arch ascends anterior to the right pulmonary artery and bifurcation of the trachea.
• It descends posterior to the root of the left lung.

Question 4

Describe the structure of the thoracic aorta, including branches.

Answer 4

• Ascending aorta arises from left ventricle
• First gives off coronary artery
• Aortic arch bends over the pulmonary veins and gives off:
  
  • Brachiocephalic artery -> Divides into right subclavian and right common carotid arteries
  • Left common carotid artery
  • Left subclavian artery
• Descending aorta gives off:
  
  • Oesophageal arteries -> Supply the middle third of the oesophagus.
  • Bronchial arteries -> Supply the lung parenchyma.
  • Posterior intercostal arteries -> Supply the intercostal spaces from the dorsal aspect.
  • Superior phrenic arteries [EXTRA]
  • Pericardial branches [EXTRA]
• Descending aorta leaves thorax at the the aortic hiatus of the diaphragm at T12

Question 5

At what level does the descending aorta cross the diaphragm?

Answer 5

T12

Question 6

Describe the aortic supply of the thoracic cage.

Answer 6

• Each subclavian arteries give off the internal thoracic arteries that run down the anterior side of the thorax
• The internal thoracic arteries give off the anterior intercostal arteries
• The descending aorta gives off the posterior intercostal arteries

Question 7

What do the bronchial and oesophageal arteries arise from?

Answer 7

Descending thoracic aorta

Question 8

Where is the ligamentum arteriosum found?

Answer 8

Between the aorta and pulmonary vein

Question 9

What is a thoracic aortic aneurysm?

Answer 9

• A ballooning of the aorta above the diaphragm, which predisposes the vessel to rupture due to weakening of the vessel wall.
• If a rupture occurs, the mortality rate is as high as 80%.
• 20% of these aneurysms are linked to family history.
• Aneurysms may be treated using either open surgery or endovascular stent graft insertion.

Question 10

At what level does the abdominal aorta begin and end?

Answer 10

• Begins at T12, at the diaphragmatic hiatus
• Ends at L4 by dividing into the left and right common iliac arteries

Question 11

Where in the abdomen does the abdominal aorta descend?

Answer 11

Anterior to the vertebral bodies within the retroperitoneum.

Question 12

What are the 3 types of branches arising from the descending abdominal aorta?

Answer 12

• Unpaired visceral
• Paired visceral
• Paired segmental branches

Question 13

Describe the branches of the abdominal aorta.

Answer 13

• Unpaired visceral:
  
  • Coeliac (T12) -> Supplies derivatives of the foregut. Branches into the left gastric artery, splenic artery and common hepatic artery.
  • Superior mesenteric artery (L1) -> Supplies derivatives of the midgut. Branches include jejunal, ileal, ileocolic, right colic and middle colic arteries.
  • Inferior mesenteric artery (L3) -> Supplies derivatives of the hindgut. Branches include the left colic, sigmoid and superior rectal arteries.
• Paired visceral:
  
  • Middle adrenal (suprarenal) artery (L1) -> Help supply to adrenal glands along with the superior and inferior suprarenal arteries.
  • Renal artery (L1/2) -> Supplies kidneys.
  • Gonadal artery (L2) -> Either the testicular artery or the ovarian artery.
• Paired segmental [EXTRA]
  
  • Inferior phrenic artery -> Supplies the underside of the diaphragm.
  • Lumbar arteries -> Multiple sets of paired arteries that supply the muscles of the back, vertebrae and intervertebral discs.

Question 14

Describe an abdominal aortic aneurysm.

Answer 14

• Abdominal aortic aneurysms are far more common than thoracic aortic aneurysms and all men aged 65 are invited to an ultrasound screening scan to identify those at risk.
• Aneurysms can interfere with the blood supply of many of the structures reliant on the abdominal aorta, including the kidneys and GI tract.
• Rupture of these aneurysms can be rapidly fatal.

Question 15

What does the abdominal aorta bifurcate into and at what level?

Answer 15

Into the common iliac arteries at L4

Question 16

What do the common iliac arteries divide into?

Answer 16

• Internal iliac artery
• External iliac artery

Question 17

What are the branches of the internal iliac arteries and what do they supply?

Answer 17

• To pelvic organs:
  
  • Middle rectal
  • Vesical
  • Uterine
• To body wall:
  
  • Superior gluteal
  • Inferior gluteal
  • Obturator
• To perineum:
  
  • Pudendal

Question 18

What does the external iliac artery become and where?

Answer 18

Femoral artery at the inguinal ligament

Question 19

For the inferior epigastric artery, describe:

• Origin
• Function
• Importance

Answer 19

• Origin -> External iliac artery
• Function -> Supplies the anterior abdominal wall, deep abdominal wall of the pubic and lower umbilical regions, and spermatic cord
• Importance -> Forms the lateral border of the inguinal triangle

Question 20

Describe the structure of the vena cava and what it drains.

Answer 20

• Superior vena cava drains the head and upper limbs
  
  • Drains the right brachiocephalic and left brachiocephalic veins, which each drain their corresponding internal jugular and subclavian veins
• Inferior vena cava drains the abdomen, pelvis and lower limbs
  
  • Drains multiple tributaries, including the common iliac veins

Question 21

Describe the organisation of major veins in the thorax and abdomen.

Answer 21

• Superior vena cava:
  
  • Confluence of right and left brachiocephalic veins, which are confluences of:
    
    • Internal jugular veins (drain head) and subclavian veins (drain external jugular veins and upper limb)
  • Drain the azygos vein just before the SVC enters the right atrium
    
    • Intercostal veins drain into the azygos vein on the right and the hemi-azygos veins on the left side of the thorax. The hemi-azygous veins drain into the azygous vein.
• Coronary sinus drains heart
• Inferior vena cava:
  
  • Drains the hepatic portal vein, which drains liver and alimentary tract (indirectly, via the hepatic portal veins)
  • Drains the adrenals, kidneys, gonads, pelvic organs (corresponding veins to arteries)
  • Drains the common iliac veins

Question 22

Describe the venous drainage of the thoracic cage.

Answer 22

• Posterior intercostal veins drain into the azygos, hemiazygos and accessory hemiazygos veins
• The hemiazygos and accessory hemiazygos veins drain into the azygos veins
• The azygos vein drains into the superior vena cava

Question 23

What are some easy ways to remember the level at which these structures cross the diaphragm:

• Vena cava
• Aorta
• Vegus nerve
• Oesophagus

Answer 23

• Vena cava -> T8 -> There are 8 letters in vena cava
• Aorta -> T12 -> Idk good luck
• Vagus nerve -> T10 -> There are 10 letters in vagus nerve and it is the 10th cranial nerve
• Oesophagus -> T10 -> There are 10 letters in oesophagus

Question 24

How many pulmonary arteries are there?

Answer 24

2 -> A left and a right one.

Question 25

Describe the venous drainage of the lungs and bronchi.

Answer 25

* Pulmonary veins drain the lungs -\> Drain into the left atrium of the heart. * Bronchial veins drain the larger bronchi and structures at the roots of the lungs -\> The right side drains into the azygos vein, while the left side drains into the left superior intercostal vein or the accessory hemiazygos vein.

Question 26

How many pulmonary veins are there?

Answer 26

4 -\> A superior and inferior on each side.

Question 27

Label the hila of the right and left lungs. (Right is on the left and left is on the right)

Answer 27

Note: The posterior is in the middle, the anterior is to the sides.

Question 28

Summarise the venous drainage of the abdomen.

Answer 28

Much of the venous system of the abdomen follows the same pattern as the arteries, although there are some exceptions: 1. There are no inferior vena cava tributaries from the spleen, pancreas, gallbladder or abdominal GI tract, as these structures drain into the hepatic portal system first. 2. There is no coeliac vein – instead, in most individuals, the splenic vein and superior mesenteric vein join together to form the hepatic portal vein behind the neck of the pancreas. The inferior mesenteric vein usually drains into the splenic vein before it forms the hepatic portal vein, although there is a lot of anatomical variation. 3. The left gonadal and left adrenal veins drain into the left renal vein, rather than directly into the inferior vena cava.

Question 29

Describe the lymph nodes of the thorax and abdomen.

Answer 29

* The **cisterna chyli** drains the **chains of nodes around the aorta** (found at the origin of the coeliac, superior mesenteric and inferior mesenteric arteries), as well as the **external and internal iliac nodes** * The **thoracic duct** drains lymph from the cisterna chyli into the junction between the left internal jugular and left subclavian veins

Question 30

Where in the lungs are lymph nodes found?

Answer 30

At the hilum.

Question 31

Describe the position of the spleen. Include surface markings.

Answer 31

* Intra-peritoneal * Found within the left upper quadrant of the abdomen, behind 9th-11th ribs. * Inferiorly, the spleen is related to the colon at the splenic flexure.

Question 32

Describe the arterial supply and venous drainage of the spleen.

Answer 32

* Arterial supply -\> Splenic artery (arising from coeliac trunk) * Venous drainage -\> Splenic vein

Question 33

Draw the surface anatomy of the spleen.

Answer 33

Question 34

What is the carotid bifurcation?

Answer 34

* It is the point where the common carotid artery divides into the internal and external carotid arteries * This usually occurs at the upper border of the thyroid cartilage, at around the level of the C4.

Question 35

Compare what the internal and external carotid arteries supply.

Answer 35

* Internal carotid artery -\> Supplies brain, eyes and forehead through the carotid canal in the skull * External carotid artery -\> Supplies areas of the head and neck that are exterior to the cranium

Question 36

What are the branches of the external carotid artery?

Answer 36

* Superior thyroid artery -\> Supplies the superior part of the thyroid and the larynx. * Lingual artery -\> Supplies the floor of the mouth, including the tongue. * Facial artery -\> Supplies the face. * Maxillary artery -\> Supplies deep structures of the face. Extra: * Ascending pharyngeal artery -\> Supplies the tonsils. * Superficial temporal artery -\> Supplies temple and scalp.

Question 37

The middle meningeal artery is a branch of which artery?

Answer 37

Maxillary artery

Question 38

Answer 38

Question 39

What artery is this?

Answer 39

Superior thyroid artery

Question 40

What artery is this?

Answer 40

Facial artery

Question 41

What artery is this?

Answer 41

Lingual artery

Question 42

What artery is this?

Answer 42

Maxillary artery

Question 43

Describe the branches of the subclavian arteries.

Answer 43

* Vertebral artery -\> Join to form the basilar artery. * Internal thoracic (and other branches to neck and chest) -\> Run anteriorly downward into the thorax behind the costal cartilages. Give off the anterior intercostal arteries. * Inferior thyroid artery -\> Supplies thyroid and parathyroid glands.

Question 44

Which nerve is the inferior thyroid artery closely related to?

Answer 44

Recurrent laryngeal branch of the vagus

Question 45

Draw the carotid, facial and superficial temporal pulse points.

Answer 45

Note: The superficial temporal pulse point is over the zygomatic process.

Question 46

Name the main deep and superficial veins draining the head and neck.

Answer 46

* Deep veins -\> Internal jugular, Subclavian * Superficial veins -\> External jugular, Anterior jugular

Question 47

Describe the venous drainage of the head and neck.

Answer 47

Superficial veins: * Anterior jugular veins * Drain the neck * Drain into the external jugular vein just before they enter the subclavian veins * External jugular veins * Drain the superficial tissues of the skull and the posterior and deep parts of the face * Drain into the subclavian veins (before they join with the internal jugular veins) Deep veins: * Internal jugular veins * Drain the brain and parts of the face * Drain into the subclavian veins, forming brachiocephalic veins * Subclavian veins The confluence of the brachiocephalic veins forms the superior vena cava. Summary: Anterior jugular drains into external jugular, which drains into the subclavian. Subclavian and internal jugular join to form brachiocephalic, which join to form the SVC.

Question 48

What defines whether veins draining the face and neck are deep or superficial?

Answer 48

The veins lie either superficial or deep to the investing layer of deep fascia in the neck.

Question 49

What are central lines?

Answer 49

* Also known as central venous catheterisation, this procedure involves the insertion of a sterile tube (catheter) into either the subclavian or internal jugular veins, permitting blood sampling and long-term administration of drugs and artificial nutrition. * Central lines have greater longevity, security and variety of uses compared to peripherally placed catheters.

Question 50

Describe the jugular venous pressure.

Answer 50

* The JVP is commonly examined during cardiovascular exams. * It is normal to observe pulsations from the internal jugular vein within the neck, particularly when the patient is lying down. * The JVP can be differentiated from the carotid pulse by being a double waveform, variable with respiration, lost on pressure and by not being palpable.

Question 51

Describe lymphatics of the head and neck.

Answer 51

* Lymphatics follow the internal, anterior and external jugular veins, forming cervical trunks * There are superficial lymph node groups that drain the scalp, face and neck * All lymphatics of the head and neck then ultimately drain into the deep cervical lymph node groups, located along the internal jugular vein. * This lymph is then passed to the jugular lymphatic trunk, which drains to the thoracic duct on the left side or the internal jugular vein on the right side. Superficial nodes -\> Deep nodes -\> Thoracic duct on left side

Question 52

Where does lymph from the head and neck ultimately drain?

Answer 52

* On the left side -\> Into the thoracic duct * On the right side -\> Into the internal jugular vein [EXTRA]

Question 53

What are the different superficial lymph nodes of the head and neck?

Answer 53

1. Submental -\> Medial lower lip and chin 2. Submandibular -\> Medial orbit, cheek and upper lip and most the external nose 3. Parotid (preauricular) -\> Eyelids, external nose and lateral cheek 4. Mastoid 5. Occipital

Question 54

What are the different deep lymph nodes of the head and neck?

Answer 54

Upper and lower deep cervical (labelled

Question 55

What are the retropharyngeal lymph nodes?

Answer 55

The retropharyngeal lymph nodes lie behind the superior pharynx and are responsible for draining the nasopharynx and auditory meati.

Question 56

What drains lymph from the tongue?

Answer 56

Submental and submandibular nodes

Question 57

What are adenoids?

Answer 57

* They are tonsils * They are found at the roof of the nasopharynx * They can be infected and enlarged

Question 58

What are the different tonsils you need to know?

Answer 58

* Lingual tonsil (at the posterior base of the tongue) * Palatine tonsils (the common tonsils, located between the palatoglossal and palatopharyngeal arches) * Adenoid tonsils (located in the roof of the nasopharynx)

Question 59

What is Waldeyer's tonsillar ring?

Answer 59

Waldeyer’s Tonsillar Ring is a ring of lymphatic tissue that surrounds the naso- and oropharynx, consisting of the two adenoid tonsils (located in the roof of the nasopharynx), two tubal tonsils (located at the opening of the Eustachian tube), two palatine tonsils (the common tonsils, located between the palatoglossal and palatopharyngeal arches) and one lingual tonsil (at the posterior base of the tongue).

Question 61

What are the two main arteries supplying the brain?

Answer 61

* Vertebral arteries: * Provide about 20% of the total supply * Supply the posterior part of the cerebrum and the contents of the posterior cranial fossa (inc. brainstem and cerebellum) * Internal carotid arteries: * Provide about 80% of the total supply * Supply the anterior and middle parts of the cerebrum and the diencephalon.

Question 62

How do the vertebral arteries enter the skull?

Answer 62

Through the foramen magnum, passing along the ventral side of the medulla.

Question 63

Describe the path of the vertebral arteries and the arteries they form.

Answer 63

* **Subclavian arteries** give off the **vertebral arteries**, which enter the skull via the foramen magnum, passing along the ventral medulla. * The vertebral arteries give off the **posterior inferior cerebellar arteries (PICA)** and also give off branches that join to form the **anterior spinal artery**. * At the lower border of the pons, the vertebral arteries unite to form the **basilar artery**. * The basilar artery gives off the **anterior inferior cerebellar arteries**, **pontine arteries** and the **superior cerebellar artery**. * It then ends in the **posterior cerebral arteries**, which supply the occipital lobes and inferomedial temporal lobes. * The posterior cerebral arteries at the start of their course give off the **posterior communicating arteries**, which form part of the Circle of Willis. Summary: * Subclavian * Vertebral * Posterior inferior cerebellar arteries * Anterior spinal artery * Basilar * Anterior inferior cerebellar arteries * Pontine arteries * Superior cerebellar arteries * Posterior cerebral arteries * Posterior communicating arteries

Question 64

Draw the path of the basilar artery.

Answer 64

Question 65

Describe the path of the internal carotid arteries and the arteries they form.

Answer 65

* **Common carotid** **arteries** give off the **internal carotid arteries**, which enters the skull through the carotid canal (in the petrous portion of the temporal bone). * First, the internal carotid arteries give off the **ophthalmic artery** that supply all the structures in the orbit as well as some structures in the nose, face and meninges. * Then, the internal carotid arteries give off the **posterior communicating arteries**, which join the posterior cerebral arteries (originating from the vertebral arteries) as part of the Circle of Willis. * Finally, the internal carotid arteries terminate as the **anterior** and **middle cerebral arteries**. * Anterior cerebral arteries supply the frontal lobes and superior medial parietal lobes. They also give off the **anterior communicating arteries** (part of the Circle of Willis) that connect with the opposite anterior cerebral artery. * Middle cerebral arteries supply the lateral cerebral cortex, anterior temporal lobes and the insular cortices.

Question 66

Summarise the areas of the outer brain supplied by each of the cerebral arteries.

Answer 66

* Blue = Anterior cerebral artery * Red = Middle cerebral artery * Yellow = Posterior cerebral artery

Question 67

Summarise the areas of the sagittal cross-section of the brain supplied by each of the cerebral arteries.

Answer 67

* Blue = Anterior cerebral artery * Red = Middle cerebral artery * Yellow = Posterior cerebral artery

Question 68

What are pontine arteries?

Answer 68

A number of small vessels which come off from either side of the basilar artery and supply the pons and adjacent parts of the brain.

Question 69

What are the posterior inferior cerebellar arteries?

Answer 69

* They are large branches of the vertebral arteries. * They supply the cerebellum.

Question 70

What are the spinal arteries and what do they arise from?

Answer 70

* They are the arteries that supply the spinal cord * There is one anterior spinal artery -\> It arises from the vertebral arteries sending branches that converge * There are two posterior spinal arteries -\> They arise from the vertebral artery in 25% of humans or the posterior inferior cerebellar artery (a branch of the vertebral artery) in 75% of humans.

Question 71

What is the artery of Adamkiewicz?

Answer 71

* It is a major artery that joins the the anterior spinal artery in the lower one-third of the spinal cord, providing reinforcement of supply. * It typically arises from a left posterior intercostal artery at the level of the 9th to 12th intercostal artery, which branches from the aorta, and supplies the lower two-thirds of the spinal cord via the anterior spinal artery.

Question 72

Where is the Circle of Willis found?

Answer 72

It encloses the optic chiasm.

Question 73

What is the Circle of Willis?

Answer 73

* It is the joining area of several arteries at the inferior side of the brain. * This is due to the anterior and posterior communicating arteries linking vessels derived from the internal carotid and vertebro-basilar systems.

Question 74

Label this.

Answer 74

Question 75

How do internal carotid arteries enter the skull?

Answer 75

* Through the carotid canal (in the petrous portion of the temporal bone). * They then travel along the foramen lacerum.

Question 76

What is the middle meningeal artery?

Answer 76

* It is one of the branches of the maxillary artery, which is a branch of the external carotid artery. * It passes through the foramen spinosum to supply the dura mater.

Question 77

Answer 77

Question 78

What imaging technique is this?

Answer 78

MRI

Question 79

What imaging technique is this?

Answer 79

Contrast CT

Question 80

Label this angiogram.

Answer 80

Question 81

What is the large artery seen in this angiogram?

Answer 81

Anterior cerebral artery

Question 82

What artery is this?

Answer 82

Middle cerebral artery

Question 83

What artery is this?

Answer 83

Posterior cerebral artery

Question 84

What artery is this?

Answer 84

Anterior cerebral artery

Question 85

What are the perforating arteries in the brain?

Answer 85

They are small arteries that come off the Circle of Willis, supplying the surface of the brain. They include: * Anterior perforating arteries * Posterior perforating arteries

Question 86

What functional areas do the anterior cerebral arteries supply?

Answer 86

* Supply the medial surfaces of the frontal and parietal lobes. * These regions correspond to the motor and sensory cortices for the lower limb.

Question 87

What functional areas do the middle cerebral arteries supply?

Answer 87

* Supply the lateral surfaces of the frontal, parietal and temporal lobes. * This corresponds to the primary motor and sensory cortices for the whole body, excluding the lower limb. * The artery also supplies the auditory cortex and the insula.

Question 88

What functional areas do the posterior cerebral arteries supply?

Answer 88

Supply the visual cortex of the occipital lobe and the inferomedial aspect of the temporal lobe.

Question 89

What type of haemorrhage is the circle of Willis susceptible to?

Answer 89

Subarachnoid haemorrhage

Question 90

Describe the relation of the internal carotid artery to the cavernous sinus and abducens nerve.

Answer 90

* It passes through the cavernous sinus * It passes more medially than the abducens nerve

Question 91

What blood vessel is this and what is the function?

Answer 91

* Vertebral arteries * Supply the upper spinal cord, cerebellum, brainstem, occipital lobes and part of the temporal lobes.

Question 92

What blood vessel is this and what is the function?

Answer 92

* Internal carotid arteries * Supply the anterior and middle parts of the cerebrum and the diencephalon.

Question 93

What blood vessel is this and what is the function?

Answer 93

* Basilar artery * It supplies the cerebellum, brainstem, occipital lobes and part of the temporal lobes.

Question 94

What blood vessel is this and what is the function?

Answer 94

* Middle cerebral arteries * Supply the lateral cerebral cortex, anterior temporal lobes and the insular cortices.

Question 95

What blood vessel is this and what is the function?

Answer 95

* Anterior cerebral arteries * Supply the frontal lobes and superior medial parietal lobes.

Question 96

What artery is this?

Answer 96

Anterior communicating artery

Question 97

Draw the different CNS sinuses.

Answer 97

Note that the internal cerebral veins join to form the great cerebral vein just before the straight sinus.