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Flashcards in Week 1 Deck (72)
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1

Which body cavity is the heart located?

Mediastinum - posterior to sterum, anterior to spinal column, medical to lungs, anterior to diaphragm

2

What is the heart's orientation?

Posterior base, anterior apex, tilted to the left, RV anterior

3

Dextrocardia is what?

A condition when the orientation of the heart is reversed, in a mirror image

4

What is the average weigh to a heart

250-300g (person dependent)

5

What are the 3 layers of the heat?

Endocardium, myocardium, epicardium

6

What is the myocardium?

Made up of cardiomyocytes which contain the contractile proteins for muscular contraction

7

What is the endocardium?

Innermost layer of the heart, made up of smooth endothelial cells

8

What is the epicardium

Also known as the visceral pericardium. Made up of squamous epithelial cells that overlie connective tissue.

9

How are cardiac muscle fibres orientated?

orientated spirally in 4 groups: two groups wind around both ventricles, 3rd group around both ventricles and 4th innermost group winds around only the LV.

10

What is the layer surrounding the heart called?

Pericardium which is a double-walled sac

11

What is the function of the pericardium?

Lubrication, shock absorber, protection (mechanical/infection), holds heart in place

12

What are the two layers of the pericardium called?

1. outer fibrous pericardium, 2. inner serous pericardium

13

What is the fibrous pericardium composed of?

Tough, white, fibrous connective tissue

14

Where does the fibrous pericardium attach?

Diaphraghm, great vessels, sterum

15

What are the two layers of the serous pericardium?

1. outer parietal layer (lines the inside of the fibrous pericardium), 2. inner visceral layer

16

What is the space between the visceral and parietal layer called?

Pericardial cavity - filled with 10-20ml of pericardial fluid

17

What is pericardial effusion?

Excess pericardial fluid in the pericardial space. This can reduce the ability of the heart to pump (cardia tamponade) and reduce the voltage picked up by skin electrodes during ECG

18

Name the great vessels of the heart

Superior vena cava, inferior vena cave, aorta, pulmonary artery, pulmonary veins (of which there are 4)

19

Where does the aortic arch lie?

behind the heart

20

Name the 4 compartments of the heart

left atria, left ventricle, right atria, right ventricle

21

What can the atria be considered as?

Blood volume reservoirs

22

Explain the flow of blood through the heart

1. right atria receives deoxygenated blood from vena cava
2. right ventricle receive deoxygenated blood from right atria
3. deoxygenated blood leaves the heart via pulmonary artery
4. oxygenated blood enters the left atria via the 4 pulmonary viens
5. oxygenated blood enters the left ventricle from the left atria
6. oxygenated blood leaves the heart vai the aorta

23

What separates the two atria and two ventricles?

Interatrial septum and interventricular septum

24

Other than the vena cave, from where else does deoxygenated blood drain into the right atria?

Coronary sinus - deoxygenated blood from the myocardium

25

Why is the LV wall thicker?

The left side of the heart operates under higher pressures and so it requires to do more stroke work.

26

What is the function of valves?

To prevent the backflow of blood (regurgitation) and thus, maximise the efficiency of blood circulation

27

Name the valves of the heart

1. Tricuspid valve separates the right atria and ventricle
2. Pulmonic valve separates the right ventricle and pulmonary artery
3. Mitral valve separates the left atria and ventricle
4. Aortic valve separates the left ventricle and aorta

28

When do the semi-lunar valves prevent regurgitation?

During diastole

29

When do the atrio-ventricular valves prevent regurgitation?

During systole

30

How many cusps does the mitral valve have?

2