Thorax

Question 1

What is the origin of the left and right coronary artery?

Answer 1

Left and right aortic sinuses behind the left and right flap of the aortic valve

Question 2

The LCA passes between the pulmonary trunk and L auricle.

Name the branches of the LCA and their distribution

Answer 2

LCA - L atrium, ventricle, IVS, AV bundle

Left anterior descending (LAD or anterior interventricular artery) - supplies R ventricle, L ventricle, anterior 2/3 IVS

Left marginal artery - L ventricle

Left circumflex artery - L atrium and ventricle

Question 3

The RCA passes to the right of the pulmonary trunk along the coronary sulcus

Name the branches of the RCA and their distribution

Answer 3

RCA - R atrium, SA and AV node, posterior part of IVS

Righ marginal artery (RMA) - supplies R ventricle and apex

Posterior interventricular artery (80-85%) - R and L ventricles and posterior interventricular septum

Question 4

Name the main tributaries of the coronary sinus

Answer 4

Great cardiac vein
Small cardiac vein
Middle cardiac vein
Posterior cardiac vein

Question 5

Describe the layers of the pericardium

Answer 5

Fibrous pericardium
Serous pericardium (divided into 2 layers)
Parietal layer
Visceral layer

Serous pericardium made up of a single layer of mesothelium

Question 6

Describe the anatomical relations of the transverse pericardial sinus

Answer 6

Posterior to the ascending aorta and pulmonary trunk
Anterior to the SVC
Superior to the L atrium

Question 7

The pericardium is innervated by which nerve?

Answer 7

Phrenic nerve C3-5

Question 8

Describe the 3 distinct layers of the heart wall

Answer 8

Endocardium - innermost layer made up of loose CT and squamous epithelial tissue

Subendocardial layer - loose fibrous tissue contains vessels, nerves, conducting system and purkinje fibres

Myocardium - involuntary striated muscle

Subepicardial layer

Epicardium - visceral layer of serious pericardium - composed of CT and fat - secretes pericardial fluid - lined by squamous epithelium

Question 9

The SA node is located within the wall of the _____?

Answer 9

Right atrium

Question 10

Describe the sequence of electrical events during one full contraction of the heart muscle

Answer 10

AP generated in SA Node - spreads across atria resulting in contraction

Spreads to AV node located within IVS near opening of coronary sinus - signal delayed before reaching bundle of His down the IVS to purkinje fibres

Question 11

The trachea begins at which level?

Answer 11

C6

Question 12

The trachea and bronchi are lined with which type of epithelium?

Answer 12

Ciliated pseudostratified columnar epithelium with interspersed goblet cells

Question 13

The trachea is held open by C-shaped cartilaginous rings supported by the trachea list muscle. Name the following with regards to the trachea -

1. 1. Sensory innervation
2. 2. Arterial supply
3. 3. Venous drainage

Answer 13

1. 1. Recurrent laryngeal nerve
2. 2. Inferior thyroid artery
3. 3. Branchiocephalic, ayzgos and accessory hemiazygos veins

Question 14

Within the lungs, the primary bronchi divide into the lobar (secondary) bronchi - each supplying the lobes of the lungs - and further divide into segmental (tertiary) bronchi. Name the following:

1. 1. Sensory innervation
2. 2. Arterial supply
3. 3. Venous drainage

Answer 14

1. 1. Vagus nerve
2. 2. Bronchial arteries
3. 3. Bronchial veins

Question 15

The horizontal fissure of the right lung corresponds with level of the ________ anteriorly?

Answer 15

4th rib

Question 16

Describe the lymphatic drainage of the lungs

Answer 16

Arises from 2 lymphatic plexuses

Superficial (subpleural) plexus - drains parenchyma

Deep - drains structures of the lung root

Plexuses drain into the tracheobronchial nodes around the bifurcation of the trachea and main bronchi