4. Anatomy of the CVS 1

Question 1

What is the function of arteries?

Answer 1

distribute blood AWAY from heart

Question 2

What is the function of capillaries?

Answer 2

exchange of nutrients

Question 3

What is the function of veins?

Answer 3

collect and return blood TOWARDS the heart

Question 4

What is the function of the lymphatics?

Answer 4

drain excess extracellular fluid from tissues and plays a role in metastases

Question 5

Where is the heart located in the thoracic chest?

Answer 5

middle mediastinum

Question 6

Which region of the body doesn’t have blood vessels? How does it get its nutrient supply?

Answer 6

cartilage; gets its nutrients from diffusion from underlying connective tissue

Question 7

Which 2 regions of the body doesn’t have lymphatics? How does it get its nutrient supply?

Answer 7

• brain

- eye

Question 8

What are 2 main circulations in cardiovascular system?

Answer 8

1. pulmonary (heart-lungs-heart)

2. systemic (heart-body-heart)

Question 9

What are 2 additional important circulatory systems?

Answer 9

1. hepatic portal circulation

2. lymphatic system

Question 10

In which region is the apex of heart found?

Answer 10

l. ventricle ( left anterior side)

Question 11

In which region is the base of the heart found?

Answer 11

l.atrium (posteriorly)

Question 12

What is right border of heart formed by?

Answer 12

right atrium

Question 13

What is the left border of the heart formed by?

Answer 13

l. ventricle

Question 14

What is the function of the auricles in the heart?

Answer 14

• store blood

- increase capacity of the atrium (and the volume of blood it’s able to contain)

Question 15

What veins drain coronary arteries?

Answer 15

Cardiac veins (wrapped around the heart)

Question 16

Above which vertebral region does superior mediastinum lie?

Answer 16

above T4

Question 17

Where does the inferior mediastinum start and end at?

Answer 17

Starts at T4 and ends at the diaphragm

Question 18

What are mediastinum divided into?

Answer 18

• superior

- inferior; anterior, middle and posterior

Question 19

What does anterior mediastinum contain?

Answer 19

fat, remnants of thymus gland (which disappears at puberty)

Question 20

What is caused if thymus remnants spread into lungs and what surgical procedure is needed?

Answer 20

thymoma; thymectomy needed

Question 21

Define mediastinum.

Answer 21

• central compartment of thoracic cavity surrounded by loose connective tissue

Question 22

Where EXACTLY is the apex of the heart found?

Answer 22

5th left intercostal space in the midclavicular line

Question 23

What is the difference in the position of the heart in children?

Answer 23

-positioned higher in children and lies more horizontal

Question 24

If a person is standing up, what will happen to the heart?

Answer 24

May appear slightly lower than 5th left intercostal space in the midclavicular line

Question 25

What is situs inversus?

Answer 25

condition where all organs lie on the opposite sides of the chest (swapped), people are asymptomatic (apex on right and aorta on left)

Question 26

At what vertebral landmark is the sternal angle located?

Answer 26

T4

Question 27

What is anterior to the heart? (4)

Answer 27

1. sternum 2. costal cartilages 4-7 3. anterior edges lungs and pleurae 4. thymic remnants

Question 28

What is posterior to the heart? (3)

Answer 28

1. oesophagus 2. descending aorta 3. thoracic vertebrae 5-8

Question 29

What is lateral to the heart? (2)

Answer 29

1. lungs | 2. phrenic nerves (which also give sensory fibres to pericardium as much as to the diaphragm)

Question 30

What is inferior to the heart? (1)

Answer 30

1. central tendon of diaphragm

Question 31

What 3 layers make up the heart wall?

Answer 31

1. endocardium (innermost) 2. myocardium (middle) 3. epicardium (outermost)

Question 32

What makes up the endocardium? (3)

Answer 32

- epithelium (flat simple squamous epithelial cells) - basement membrane - connective tissue

Question 33

What makes up the myocardium? (1)

Answer 33

1. muscle

Question 34

What makes up the epicardium?

Answer 34

1. connective tissue 2. basement membrane 3. epithelium (flat simple squamous epithelial cells)

Question 35

What makes up the epithelium of epicardium?

Answer 35

visceral pericardium

Question 36

What 2 layers are found above the visceral pericardium (epithelium of epicardium)

Answer 36

- parietal pericardium | - fibrous pericardium (outside)

Question 37

What is found between visceral pericardium and parietal pericardium?

Answer 37

pericardial cavity

Question 38

What are features of endocardium? (what does it line, what cells make it up and what does it sit on?)

Answer 38

- lines heart chambers - simple squamous epithelium sitting on the BM - sits on connective tissue

Question 39

What does endocardium form?

Answer 39

forms valves (projections on it form valves)

Question 40

What is myocardium made up of?

Answer 40

- cardiac (striated) muscle (myocytes) | - thick middle layer of heart wall

Question 41

What do the myocyte cells look like?

Answer 41

- contain lots of mitochondria | - central rounded nuclei in myocardium

Question 42

Is there a capillary bed in the myocardium?

Answer 42

Yes, a rich capillary bed

Question 43

Why are muscle bundles in different planes in myocardium?

Answer 43

to close down chamber lumen

Question 44

What are myocytes connected by?

Answer 44

intercalated discs (complex junctions that anchor structures containing gap junctions)

Question 45

What do myocytes all connected together form as they synchronise?

Answer 45

a functional syncytium as they contract in unison

Question 46

What two junctions make up the intercalated disc?

Answer 46

1. desmosomes | 2. gap junctions

Question 47

How do desmosomes connect and what is their function in cardiac cells?

Answer 47

- connect at horizonatal interface | - bind myocytes together

Question 48

How do gap junctions connect and what is their function in cardiac cells?

Answer 48

- connect at vertical interface - electrical communication - essential to coordinated cardiac cycle

Question 49

What is the epithelium of the epicardium the same as?

Answer 49

same as the visceral layer of serous pericardium

Question 50

What tissue may be found in the epicardium?

Answer 50

fatty tissue

Question 51

What features branch out from the epicardium?

Answer 51

contains main branches of coronary arteries

Question 52

What are the 4 heart chambers?

Answer 52

1. right atrium 2. left atrium 3. right ventricle 4. left ventricle

Question 53

What is the direction of blood flow controlled by?

Answer 53

valves (which prevent backflow)

Question 54

What are the 4 heart borders?

Answer 54

1. left border 2. right border 3. superior border 4. inferior border

Question 55

What makes up the left border of the heart?

Answer 55

mainly by l. ventricle (but a little bit by l.atrium also)

Question 56

What makes up the right border of the heart?

Answer 56

mainly by r. atrium (and r. ventricle below)

Question 57

What is the function of valves?

Answer 57

control direction of blood flow by preventing back flow

Question 58

Where are cusps on valves derived from?

Answer 58

thin structures derived from endocardium

Question 59

How do valves work?

Answer 59

passively

Question 60

What 2 structures prevent valve failure and their prolapse?

Answer 60

1. chordae tendinae | 2. papillary muscles

Question 61

What are the most common abnormalities in heart valves? (2)

Answer 61

1. incompetence; widening of valve | 2. stenosis; narrowing of valve

Question 62

What is the most common infection of the heart valves?

Answer 62

bacterial endocarditis

Question 63

What are the 4 heart valves?

Answer 63

1. Tricuspid valve 2. Mitral valve 3. Pulmonary valve 4. Aortic valve

Question 64

What is another name for tricuspid and mitral valves?

Answer 64

AV valves

Question 65

What is another name for pulmonary and aortic valves?

Answer 65

semi-lunar valves

Question 66

What is the number of papillary muscles related to?

Answer 66

number of cusps on the valve it's attached to

Question 67

How many cusps does each valve have?

Answer 67

- tricuspid; 3 - pulmonary; 3 - aortic; 3 - mitral/bicuspid; 2

Question 68

What is the cardiac skeleton made up of?

Answer 68

connective tissue

Question 69

What are 2 main functions of the cardiac skeleton?

Answer 69

1. structural support | 2. electrical insulation

Question 70

What is included in the structural support of the cardiac skeleton? (4)

Answer 70

1. atrioventricular septum 2. roots of great vessels 3. anchorage for valves 4. myoctes/ capillary network

Question 71

What is included in the electrical insulation of the cardiac skeleton? (2)

Answer 71

1. atria from ventricles | 2. myocardium from great vessels

Question 72

What are SIN and AV nodes externally modulated by?

Answer 72

- vagus nerve (keeps it at 70beats/min) | - sympathetic chain

Question 73

How many major coronary arteries are there?

Answer 73

2: right and left

Question 74

What is an aortic sinus?

Answer 74

- anatomic dilation of ascending aorta which occurs just above aortic valve - widenings between wall of aorta and each of the 3 cusps of the aortic valve - found just above coronary arteries branching

Question 75

What occurs at systole to coronary arteries blood flow?

Answer 75

- openings in aortic sinuses are SHIELDED by aortic valve cusps which open to let blood through aorta - no blood gets into coronary arteries

Question 76

What occurs at diastole to coronary arteries blood flow?

Answer 76

- recoil of the aorta closes aortic valve revealing the aortic sinuses - blood then FLOWS into coronary arteries at distole

Question 77

On which cardiac layer are coronary arteries located?

Answer 77

in the epicardium

Question 78

What happens to myocardium during diastole?

Answer 78

It RELAXES; blood can flow into capillaries

Question 79

What can blockage/occlusion of coronary arteries lead to?

Answer 79

heart attack (myocardial infarction)

Question 80

What does right coronary artery branch off into around the heart? (2)

Answer 80

1. posterior descending artery | 2. right marginal artery

Question 81

What does left coronary artery branch off into around the heart? (2)

Answer 81

1. anterior interventricular artery (left anterior descending; LAD) 2. left cirumflex artery

Question 82

What can be done to branches of coronary arteries in patients with coronary heart disease?

Answer 82

Branches can be anastomosed (joined together)

Question 83

What holds the heart in place? (3)

Answer 83

1. hangs by great vessels within fibrous pericardium 2. dense connective tissue bag 3. attachments

Question 84

What are some of the attachments which hold the heart in place? (3)

Answer 84

1. central tendon of diaphragm 2. sternum 3. roots of great vessels

Question 85

What is the heart lined with?

Answer 85

serous pericardium

Question 86

What fluid is secreted from the heart epithelium (visceral layer)?

Answer 86

pericardial fluid (lubricant)

Question 87

What is visceral layer bound to?

Answer 87

bound to he heart (epithelium of the epicardium)

Question 88

What is the parietal layer bound to?

Answer 88

bound to fibrous pericardium

Question 89

Are visceral and parietal layers continous around the heart?

Answer 89

Yes; like a closed bag around the heart

Question 90

What does the serous pericardium ensure the heart is able to do?

Answer 90

allows freedom of movement during cardiac cycle