Anatomy of the CVS 1

Question 1

Basic functions of Arteries, Capillaries and Veins

Answer 1

Arteries - distribute blood from heart

Capillaries - exchange nutrients

Veins - collect and return blood to the heart

Question 2

Basic function of Lymphatics

Answer 2

Drain excess extracellular fluid from tissues

Question 3

Where is the cardiovascular system located?

Answer 3

• Heart: middle mediastinum.
• Blood vessels
• Lympahtics

Question 4

Do the brain and eye have lymphatics?

Answer 4

NO

Question 5

Does cartilage have blood vessels?

Answer 5

NO

Question 6

Where are the main structures of the cardiovascular system located?

Answer 6

The middle mediastinum

Question 7

What are the two main circulations of the CV system?

Answer 7

• Pulmonary circulation: heart-lungs-heart
• Systemic circulation: heart-body-heart

Also hepatic portal circulation: Lymphatic system.

Question 8

What are the great vessels of the heart?

Answer 8

• 2 L&R pulmonary veins
• Aorta: ascending, aortic arch, descending
• Superior vena cava
• Right pulmonary artery
• Left pulmonary artery
• Pulmonary trunk
• Inferior vena cava

Question 9

Between which vertebrae does the heart lie?

Answer 9

T5-8

-In recumbent position

Question 10

Where is the apex located?

Answer 10

Left ventricle: 5th left intercostal space in the midclavicular line

Question 11

Where is the left atrium located?

Answer 11

LA=base

- It is wholly posterior, lies in front of the oesophagus.

Question 12

How is the heart positioning different in children?

Answer 12

Higher in children and lies more horizontal

Question 13

What is Dextrocardia with situs inversus?

Answer 13

Dextrocardia with Situs Inversus is a rare heart condition characterised by abnormal positioning of the heart.
- In this condition, the tip of the heart (apex) is positioned on the right side of the chest. - Additionally, the position of the heart chambers as well as the visceral organs such as the liver and spleen is reversed (situs inversus).

Question 14

What is a useful landmark for the heart?

Answer 14

T4 sternal angle

Question 15

What anatomical relations are anterior to the heart?

Answer 15

• Sternum & costal cartilages 4-7
• Anterior edges lungs and pleurae
• Thymic remnants

Question 16

What anatomical relations are posterior to the heart?

Answer 16

• Oesophagus
• Descending aorta
• Thoracic vertebrae 5-8

Question 17

What anatomical relations are lateral to the heart?

Answer 17

• Lungs

- Phrenic nerve

Question 18

What anatomical relations are inferior to the heart?

Answer 18

Central tendon of diaphragm

Question 19

What are the main structures of the heart?

Answer 19

• Layers of heart wall
• Chambers
• Heart valves
• Cardiac skeleton
• Coronary arteries
• Cardiac veins
• Pericardium
• Innervation

Question 20

What are the 3 main layers of the heart wall?

Answer 20

• Endocardium (innermost):
  epithelium + basement membrane + connective tissue
• Myocardium (middle): cardiac muscle
• Epicardium (outermost):
  connective tissue + basement membrane + epithelium

Question 21

Features of Endocardium

Answer 21

• Lines heart chambers
• Simple squamous epithelium sitting on the basement membrane
• Sits on connective tissue
• Forms valves

Question 22

Features of Myocardium

Answer 22

• Thick middle layer of heart wall
• Cardiac muscle (myocytes): branching fibres
• Striated muscle, lots of mitochondria, single-central nucleus
• Rich capillary bed
• Muscle bundles in different planes to close down chamber lumen
• Myocytes connected by intercalated discs

Question 23

Features of Epicardium

Answer 23

• Outer layer of heart wall
• Simple squamous epithelium + BM + connective tissue
• Epithelium = visceral layer of serous pericardium
• Epicardium contains main branches of coronary arteries
• May be fatty

Question 24

What are the chambers of the heart?

Answer 24

• Right atrium
• Right ventricle
• Left atrium
• Left ventricle

Direction of blood flow is controlled by valves

Question 25

What are the different borders of the heart?

Answer 25

- Superior border - Right border - Left border - Inferior border

Question 26

Features of heart valves

Answer 26

- Control direction of blood flow - Cusps: thin structures derived from endocardium - Work passively - Chordae tendineae and papillary muscle prevent valve failure

Question 27

Clinically important problems with heart valves

Answer 27

- Abnormalities( imcompetence= widening, stenosis= narrowing) - Infection (bacterial endocarditis)

Question 28

What are the 4 valves of the heart?

Answer 28

- Pulmonary valve - Aortic valve - Mitral valve - Tricuspid valve

Question 29

Which valves are the atrioventricular valves?

Answer 29

Tricuspid and Mitral -Control blood flow from the atria to the ventricles.

Question 30

What do the aortic valve and pulmonary valve control (semilunar valves)?

Answer 30

Control blood flow out of the ventricles

Question 31

What is the mitral valve known as?

Answer 31

The bicuspid valve

Question 32

How many cusps do the semilunar valves (aortic and pulmonary valves) have?

Answer 32

3 cusps

Question 33

Structural support of Fibrous cardiac skeleton

Answer 33

- Atrioventricular septum - Roots of great vessels - Anchorage for valves - Myocytes/capillary network

Question 34

Fibrous cardiac skeleton electrical insulation

Answer 34

- Atria from ventricles | - Myocardium from great vessels

Question 35

Features of coronary arteries

Answer 35

- Right and left - At systole openings in aortic sinuses shielded by aortic valve cusps - At diastole elastic recoil of aorta closes aortic valve and blood enters arteries - Located in epicardium - At diastole myocardium relaxing and blood can flow into capillaries - Occlusion (Blockage) = bad news – heart attack! - Must know main branches.

Question 36

What holds the heart in place?

Answer 36

- It “Hangs” by great vessels within fibrous pericardium - Dense connective tissue bag - Attachments: Central tendon of diaphragm, Sternum, Roots of great vessels. - Lined by serous pericardium

Question 37

Features of serous pericardium

Answer 37

- Epithelium - Secretes pericardial fluid – lubricant - Visceral layer Bound to heart (=epicardium) - Parietal layer Bound to fibrous pericardium - Visceral and parietal layers continuous: gives closed bag - Allows freedom of movement during cardiac cycle