The heart and great vessels

Question 1

What is the heart contained in?

Answer 1

The pericardium

Question 2

What are the surface projections of the surface of the heart?

Answer 2

Top right = 3rd costal cartilage
Bottom right = 6th costal cartilage
Top left = 2nd costal cartilage
Bottom left = 5th intercostal space

Question 3

How many branches arise from the aorta?

Answer 3

3

Question 4

Where can the apex of the heart be palpated?

Answer 4

At the fifth intercostal space

Question 5

What is the brachicephalic artery?

Answer 5

An artery of the mediastinum which supplies blood to the RIGHT arm, head and neck by splitting into the right subcalvian artery and the right common corotid artery

Question 6

What do the right and left subclavian arteries supply?

Answer 6

The right and left arm

Question 7

What do the right and left common carotid arteries supply?

Answer 7

The right or left head and neck blood supply

Question 8

Which veins join to form the vena cava?

Answer 8

Brachiocephalic veins

Question 9

Which veins drain blood from the head?

Answer 9

The left and right internal jugular veins

Question 10

What does the heart mainly lie behind and what is the exception to this?

Answer 10

The sternum, the apex potrudes the left slightly

Question 11

What is the most obvious feature on an X-ray of the heart?

Answer 11

The arch of the aorta

Question 12

Describe the right atria

Answer 12

Pierced by the vena cava with deoxygenated blood
Thin walled with internal rough muscle
The coronary sinus is located here
Can be seen from the front of the heart

Question 13

What is the coronary sinus?

Answer 13

The coronary sinus is a collection of veins joined together to form a large vessel that collects blood from the heart muscle
It delivers less-oxygenated blood to the right atrium, as do the superior and inferior vena cava

Question 14

Describe the left atrium

Answer 14

Most posterior
Unable to see from the front of the heart
Holds blood returning from the lungs (oxygenated)

Question 15

Describe the right ventricle

Answer 15

Pumps blood to the pulmonary circulation
Has thicker walls than the atria
Has thinner walls than the left ventricle
Has papillary muscles which give rise to chordae tendinae
Contains a moderator band which prevents distension

Question 16

Describe the left ventricle

Answer 16

Forms the apex of the heart
Is the thickest chamber
Pumps blood around the systemic circulation
Has trabeculae carnae

Question 17

What are trebeculae carnae?

Answer 17

Irregular muscular columns which project from the inner surface of the right and left ventricles of the heart
Most likely to prevent suction that would occur with a flat surfaced membrane and thus impair the heart’s ability to pump efficiently

Question 18

What are pectinate muscles?

Answer 18

Parallel ridges in the walls of the atria of the heart.
They are so-called because of their resemblance to the teeth of a comb as in pecten
Increasing the power of contraction without increasing heart mass

Question 19

Where is the tricuspid valve?

Answer 19

Between the right atrium and the right ventricle

Question 20

How many leaflets does the tricuspid valve have?

Answer 20

3

Question 21

What does the pulmonary valve separate?

Answer 21

The right ventricle and the pulmonary circuit

Question 22

How many leaflets does the pulmonary valve have?

Answer 22

3

Question 23

Where is the bicuspid valve?

Answer 23

Between the left atrium and the left ventricle

Question 24

How many leaflets does the bicuspid valve have?

Answer 24

2

Question 25

What does the aortic valve separate?

Answer 25

The left ventricle and the aorta

Question 26

What is the left auricular appendage?

Answer 26

Small muscular pouch on the upper corner of the left atrium It collects oxygenated blood as it leaves the lungs and moves the blood into the left ventricle While the left ventricle contracts, the bicuspid valve shuts to prevent regurgitation of blood. Meanwhile, new blood from the lungs fills the left atrium and left auricle again for the next round of pumping

Question 27

What is the right auricular appendage?

Answer 27

Cone shaped Overlaps the root of the aorta Collects deoxygenated blood from the blood stream and moves it into the right ventricle

Question 28

What are the cordae tendinae made out of?

Answer 28

80% collagen | 20% elastin and epithelial cells

Question 29

When are the chordae tendinae relaxed?

Answer 29

As the atrioventricular valves are forced open in atrial systole

Question 30

What is the main role of the chordae tendinae?

Answer 30

They prevent the eversion and prolapse of the valves leaflets back into the atria by holding the leaflets in a closed position

Question 31

What are the papillary muscles?

Answer 31

In the ventricles and attach to the cusps of the AV valves via the chordae tendinae

Question 32

How many papillary muscles are there in total and where are they?

Answer 32

5 3 in the right ventricle 2 in the left ventricle

Question 33

When do papillary muscles contract?

Answer 33

Shortly before ventricular systole and maintain tension preventing valves being pushed back into the atrium

Question 34

What can cause papillary muscle rupture?

Answer 34

Myocardial infarction

Question 35

What can cause papillary muscle dysfunction?

Answer 35

Ischaemia

Question 36

Where is the fossa ovalis?

Answer 36

Depression seen in the right atrium at the level of the interatrial septum

Question 37

What is the fossa ovalis a remnant of?

Answer 37

A thin fibrous sheet which allows blood to pass from the right atrium to the left atrium - the foramen ovule

Question 38

What is the role of the foramen ovule in development?

Answer 38

Allows blood to pass from the right atrium to the left atrium This bypasses the non functional fetal lungs as the fetus obtains its oxygen from the placenta

Question 39

When is the fossa ovalis formed?

Answer 39

Immediately after birth as the foramen ovule closes | This enables respiration and circulation independent from the mother's placenta

Question 40

What is the ligamentum artenosum?

Answer 40

Is a small ligament that is a remnant of the ductus arteriosis It attaches the aortic arch and the left pulmonary artery

Question 41

When does the ligamentum artenosum form?

Answer 41

3 weeks after birth

Question 42

What is the role of the ductus artenosum?

Answer 42

A temporary fetal structure that sucks blood from the pulmonary arteries to the aorta to avoid pulmonary circulation in the inactive lungs

Question 43

Where is the left coronary artery and what does it split into?

Answer 43

Runs down the left ventricle | Splits anteriorly into the anterior interventricular artery and posteriorly into the circumflex artery

Question 44

What does the anterior interventricular artery supply?

Answer 44

Anterolateral myocardium, apex and the interventricular septum It supplies 50% of the left ventricle = critical vessel

Question 45

What does the circumflex artery supply?

Answer 45

The posterolateral left ventricle and also the SAN in 38% of people

Question 46

Where is the right coronary artery and what does it split into?

Answer 46

Runs down the right ventricle | Splits anteriorly into the marginal artery and posteriorly into the posterior interventricular artery

Question 47

What does the marginal artery supply?

Answer 47

All surfaces of the right ventricle

Question 48

What does the posterior interventricular artery supply?

Answer 48

The posterior interventricular septum

Question 49

What percentage of people show: a) right dominance b) left dominance c) co-dominance

Answer 49

a) 70% b) 15% c) 15%

Question 50

What does dominance depend on?

Answer 50

Which artery supplies the AV node

Question 51

Which coronary arteries are often blocked?

Answer 51

The left anterior descending - supplies blood to the interventricular septum and so supplies bundle branches of the conducting system

Question 52

Where on the chest would you place a stethoscope to hear closure of the tricuspid valve?

Answer 52

4th left intercostal space, left sternal border

Question 53

Where on the chest would you place a stethoscope to hear the mitral valve?

Answer 53

The 5th intercostal space, left mid-clavicular line

Question 54

Where on the chest would you place a stethoscope to hear the aortic valve?

Answer 54

2nd right intercostal space, right sternal border

Question 55

Where on the chest would you place a stethoscope to hear the pulmonary valve?

Answer 55

2nd intercostal space, left sternal border