CVS

Question 1

Define the boundaries divisions of mediastinum.

Answer 1

Mediastinum is the area in the chest between the lungs bounded by manubrium and sternum anteriorly, vertebral column posteriorly and lungs laterally. This is further divided into superior (above TTP), anterior, middle and posterior mediastinum.

Question 2

What are the 7 key structures found passing through the trans-thoracic plane T4/5?

Answer 2

• trachea bifurcates (called carina at bifurcation point)
• pulmonary trunk bifurcates
• concave arch aorta
• arch of azygos vein
• ligamentum arteriosum
• thoracic duct
• cardiac plexus

Question 3

Draw out the great veins and arteries of the thorax.

Answer 3

See coursebook

Question 4

Describe the path of phrenic nerve.

Answer 4

anterior rami from C3, 4, 5 merge forming phrenic nerve.

1) wrap around anterior scalene muscle and enter superior thoracic aperture (below rib 1) between subclavian artery and vein.
2) (L) travel on top of left superior intercostal vein, aorta arch and pericardium (between fibrous pericardium and parietal pleura),
2) (R) travel down on top of right brachiocephalic vein onto SVC and pericardium
3) travel down the front to the diaphragm.

Question 5

Describe the path of vagus nerve.

Answer 5

1) in the neck, positioned medial to the internal jugular vein and posterior to the common carotid artery.
2) (L) travel down between CCA and subclavian artery under superior intercostal vein to behind root of lungs.
2) (R) comes down on CCA and goes under the rib more onto trachea behind azygos vein

Question 6

What are the veins suitable for central venous lines?

Answer 6

• external jugular vein
• internal jugular vein
• subclavian vein
• femoral vein`

Question 7

What do the right and left recurrent laryngeal nerves loop around?

Answer 7

Right- right subclavian artery

Left- aortic arch

Question 8

Describe the surface anatomy of the heart.

Answer 8

• behind ribs 2-5
• 2/3 from the midline to the left
• apex lines up with left midclavicular line
• right heart border lines up with parasternal line

Question 9

Explain the innervation of the pericardium and parietal pleura.

Answer 9

Phrenic nerve --> parietal pleura, fibrous, parietal pericardium
Sympathetic chain (T1-4) --> visceral pericardium

Question 10

What are the two sinuses found at the posterior heart area.

Answer 10

transverse pericardial sinus

oblique pericardial sinus (reflection onto pulmonary vein and heart)

Question 11

What form the right, left, and inferior borders of the heart?

Answer 11

Right- right atrium
Left- Left auricle and left ventricle
Inferior- right ventricle

Question 12

List the position and branches of the right coronary artery.

Answer 12

Right coronary artery lines the atrioventricular groove/coronary sulcus and branch into

• sinoatrial nodal branch
• atrioventricular nodal branch
• marginal branch
• posterior descending interventricular branch

Question 13

List the position and branches of the left coronary artery.

Answer 13

Left coronary artery lines the anterior interventricular sulcus and branch into

• left circumflex branch
• anterior interventricular branch/ left anterior descending artery (LAD)

Question 14

Describe how are blood drained from the heart?

Answer 14

cardiac vein –> coronary sinus –> right atrium

Question 15

What are some structures and areas that can be found in the right side of the heart? (excluding those that are very obvious)

Answer 15

fossa ovalis, sinus venarum, crista terminalis, musculi pectinati, opening of coronary sinus, conus arteriosus, trabeculae carneae, septomarginal trabecula(moderator band)

Question 16

What are some structures and areas that can be found in the left side of the heart? (excluding those that are very obvious)

Answer 16

fossa ovalis, left and right pulmonary veins, coronary ostea, trabeculae carneae,

Question 17

What are two possible causes of heart murmurs?

Answer 17

Stenosis and Regurgitation

Question 18

What are the four places to listen to the heart sounds close to the valves?

Answer 18

tricuspid valve - 5th ICS, left of sternum
mitral valve- 5th ICS, along midclavicular line
pulmonary valve- 2nd ICS, left of sternum
aortic valve, 2nd ICS, right of sternum

Question 19

List the components/ path of conduction system of heart.

Answer 19

SA node –> AV node –> atrioventricular bundle (bundle of His) –> right and left bundle branches –> septomarginal trabecula (moderator band) + subendocardial branches (purkinje fibres)

Question 20

What makes up the cardiac plexus?

Explain their roles.

Answer 20

ANS- SNS (T1-5 to sympathetic trunk): +HR, +contraction force –> +BP, vasodilation of coronary arteries
PSNS (vagus nerve - CNX): -HR, -contraction force, +vasoconstriction of coronary arteries

Question 21

Describe the course of azygos vein.

Answer 21

As the SVC and IVC is not continuous, we need the azygos system to link SVC, SVC and to supply the posterior thoracic wall area and upper lumbar regions. The azygos vein is found more towards the right on the vertebral column, and 2 branches come off to the left called accessory hemiazygos veins and hemiazygos vein(lower) which all branch off to posterior intercostal veins. The azygos vein also branch off to right superior intercostal vein, right subcostal vein and right ascending lumbar vein. ^^ look at book.

Question 22

Describe the course of thoracic duct

Answer 22

• from lower to upper, move from RHS to LHS.