The heart internal structure and surface anatomy

Question 1

What is the pressure inside the pulmonary circulation?

Answer 1

12 - 16 mmHg

Question 2

What shape is the heart described as having?

Answer 2

A pyramid that has fallen on one side

Question 3

What does the sternocostal surface include?

Answer 3

• Anterior
• Right ventricle
• Right atrium

Question 4

What does the diaphragmatic surface include?

Answer 4

• Inferior
• Left ventricle
• Right ventricle (slightly)
• Seperated from base of the heart by coronary sinus

Question 5

What does the Right pulmonary surface include?

Answer 5

• Right atrium

Question 6

What does the Left pulmonary surface include?

Answer 6

• Left ventricle (cardiac impression in the left lung)

Question 7

What does the base of the heart compose of?

Answer 7

• Primarily left atrium and pulmonary veins

- Small portion of right atrium

Question 8

Where is the base of the heart located in the body?

Answer 8

• Fixed posteriorly to the pericardium, at the level of the T6(5) - T9(8) vertebrae

Question 9

Where does the apex of the heart lie in children? What is the difference between the location of the apex in children and adults?

Answer 9

The heart is more superior and lateral

Question 10

Where does the apex of the heart lie?

Answer 10

Left 5th intercostal space and 8 - 10 cm left of midline

Question 11

What does the right margin of the heart include?

Answer 11

Right atrium

Question 12

What does the left margin of the heart include?

Answer 12

The left ventricle and left auricle

Question 13

What does the inferior margin of the heart include?

Answer 13

Right ventricle and left ventricle

Question 14

Where is the fossa ovalis located?

Answer 14

On the right side of the IA septum

Question 15

What is the fossa ovalis a remenant of?

Answer 15

The foramen ovale

Question 16

Where is the opening of the SVC located on the body?

Answer 16

Deep to the joint between right 3rd costal cartilage and sternum

Question 17

What vessels which lead into the right atrium contain valves?

Answer 17

The IVC and the coronary sinus

Question 18

What percentage of venous blood from the heart enters the right atrium through the coronary sinus?

Answer 18

60%

Question 19

What is the function of the pectinate muscles?

Answer 19

To provide contractile force without making the wall of the atrium thick

Question 20

What is the name of the muscle formed within the right auricle?

Answer 20

Pectinate muscle (makes a rough surface)

Question 21

What is the outflow tract where the pulmonary trunk arises called?

Answer 21

The infundibulum (conus arteriosus)

Question 22

What are the numerous irregular muscular ridges called on the walls of the RV?

Answer 22

Trabeculae carneae

Question 23

What are the 3 types of muscles on the right ventricle wall?

Answer 23

• Trabeculae carneae
• Septomarginal trabecula (moderator band)
• Papillary muscles

Question 24

What does the septomarginal trabecula bridge?

Answer 24

The IV septum and the anterior papillary muscle. Also carries right bundle branch of AV bundle of cardiac conduction system.

Question 25

In what chamber of the heart can you find the septomarginal trabecula?

Answer 25

Right ventricle wall

Question 26

How many papillary muscles are ther usually on the right ventricle?

Answer 26

3

Question 27

When do the chorda tendinae contract?

Answer 27

Before ventricular contraction

Question 28

What are the 3 cusps of the tricuspid valve called?

Answer 28

- Anterior - Posterior - Septal

Question 29

In what direction does blood flow through the tricuspid valve?

Answer 29

Forwards and medially

Question 30

What is the base of each cusp attached to?

Answer 30

Right fibrous ring (anulus fibrosus)

Question 31

What are the three pulmonary cusps called?

Answer 31

- Anterior - Right - Left

Question 32

What is the purpose of the pulmonary sinus?

Answer 32

Helps closure of the pulmonary valves after systole

Question 33

What are the cusps of the mitral valve called?

Answer 33

Posterior and anterior

Question 34

What is the depressed area of the Interatrial septum called?

Answer 34

Falx septi

Question 35

The falx septi is a result of the fusion of what?

Answer 35

The foramen ovale

Question 36

What are the muscular ridges on the left ventricle called?

Answer 36

Trabecula carnea

Question 37

What is the thickness of the thickest wall of the left ventricle?

Answer 37

8 - 12 mm

Question 38

How many papillary muscles are there usually on the left ventricle?

Answer 38

2 (anterior and posterior)

Question 39

How many fibrous rings are around the heart?

Answer 39

4 (around AV, aortic and pulmobary valves)

Question 40

What are the fibrous structures called that are between the 4 rings?

Answer 40

The two trigones

Question 41

What are the functions of the fibrous skeleton of the heart?

Answer 41

- Points of attachment for the cusps - Maintains the patency and integrity of AV and semilunar orifices - Serves as origin/insertion for atrial and ventricular masses - Insulates atria from ventricles (keeps normal contractile flow)

Question 42

What are the layers of the heart called?

Answer 42

- Endocardium - Myocardium - Epicardium

Question 43

Where can the 4 corners of the heart be found?

Answer 43

- Right 3rd and right 6th costal cartilage (2cm right of midline) - Left 5th costal cartilage 7-9 cm left of midline (apex) - Left 2nd costal cartilage (3cm left of midline)

Question 44

Where is the surface projection of the mitral valve located?

Answer 44

Posterior to the articulation between the left 4th costal cartilage and the sternum

Question 45

Where is the surface projection of the tricuspid valve located?

Answer 45

Behind the right half of the sternum, at the level of the 4th intercostal space

Question 46

Where is the surface projection of the pulmonary valve located?

Answer 46

Posterior to the articulation between left 3rd costal cartilage and the sternum

Question 47

Where is the surface projection of the aortic valve located?

Answer 47

Posterior to the sternum, at the 3rd intercostal space on the right

Question 48

Where is the tricuspid valve (HS1) heard?

Answer 48

To the left of the lower part of the sternum near the 5th intercostal space

Question 49

Where is the mitral valve (HS1) heard?

Answer 49

The apex of the heart in the left 5th intercostal space at the midclavicular line (apex cordis)

Question 50

What is the outfow tract of the aorta called?

Answer 50

The aortic vestibule