Cardiac Physiology

Question 1

Blood enclosed in specialised vessels is what type of Circulatory system?

Answer 1

Closed

Question 2

Carries oxygenated blood from heart throughout the body. Arterial or venous circulation

Answer 2

Arterial circulation

Question 3

Returns de-oxygenated Blood back to the heart

Answer 3

venous circulation

Question 4

Characteristics of vertebrate cardiovascular system

Answer 4

Multi-chambered heart with complex valves
Blood transported in vessels
Specialist circulatory system in order to carry both oxygenated and deoxygenated blood

Question 5

Pulmonary circulation function

Answer 5

Responsible for oxygenated Blood that we need to use

Question 6

Pulmonary circulation is described as an inversed system. Explain

Answer 6

Inversion means artery carries deoxygenated blood and vein carries oxygenated Blood back to the heart

Question 7

Innovation define:

Answer 7

Process of supplying nerves to an organ or part of the body

Refers to nerve impulses, growth of nerves and control of heart via the nervous system

Question 8

Stages of mammalian cardiac development

Answer 8

Heart tube formation around week3
Two stages of developmental process:
- Pre-innervation
- Post-innervation

Question 9

Vena cava function

Answer 9

Responsible for returning Blood to the heart

Question 10

Inferior vena cava function:

Answer 10

Returns blood from lower body

Question 11

Superior vena cava function:

Answer 11

Returns Blood from the brain

Question 12

Atrioventricular ( tricuspid / mitral) valve function:

Answer 12

Responsible for stopping blood returning back into the atrium upon ventricular contraction so no regurgitation of the blood going back into the atrium

Question 13

Semilunar values function

Answer 13

Stop any black flow going into the ventricle; allows closed pressurised system of Blood travelling around the body

Question 14

Number of key tendons found within each of the ventricles: function

Answer 14

Protect the values and facilitate the expulsion of Blood from the heart

Question 15

Chambers of the heart

Answer 15

Atria
Ventricles
Intraventricular septum
AVN
Semilunar valves

Question 16

Atria function

Answer 16

Receive blood from body (vena cava) or lungs (pulmonary vein)

Question 17

Ventricles function (RIGHT)

Answer 17

Deliver blood to lungs

Question 18

Ventricles function (LEFT)

Answer 18

Deliver Blood to rest of the body

Question 19

Intraventricular septum function

Answer 19

Dividing wall between the ventricles

Question 20

Contractile cells of the heart called?

Answer 20

Cardiomyocytes

Question 21

Cells of the heart include:

Answer 21

Cardiomyocytes - contractile cells
Fibroblasts, endothelial cues etc - used to maintain integrity (ECM) and transfer of nutrients from coronary arteries

Question 22

What is responsible for laying down extracellular matrix such as collagens and other fibrous proteins?

Answer 22

Fibroblasts

Question 23

What happens to fibroblasts when disease comes?

Answer 23

They become hyperactivated which can lead to inefficient contractile properties

Question 24

Role of endothelial cells in heart

Answer 24

Transfer nutrients from a coronary circulation, so that cardiomyocytes can use them

Question 25

Levels of the heart wall from pericardium to heart interor ( endocardium)

Answer 25

Pericardium -> pericardial space -> epicardium -> myocardium -> endocardium

Question 26

Pericardial space surrounded by sac is?

Answer 26

Pericardium

Question 27

Epicardium function:

Answer 27

Lots of coronary vessels Responsible for providing the heart with Blood

Question 28

Function of fat cells in heart wall

Answer 28

For rapid conversion to energy

Question 29

Location of cardiomyocytes

Answer 29

Myocardium

Question 30

Endocardium layer: inside of the heart. Subdivides into:

Answer 30

Endothelial layer: Subendocardial layer Subendothelial layer Endothelium

Question 31

Coronary arteries function:

Answer 31

Supply Blood a throughout the myocardium

Question 32

What supplies the left side of the heart with blood, including LAD and circumflex systems

Answer 32

Left coronary arteries

Question 33

When does myocardial perfusion occur?

Answer 33

In diastole (cardiac relaxation)

Question 34

Right corny arteries function

Answer 34

Supply the right side of the heart with blood, including the areas controlling cardiac rhythm (SAN and AVN nodes)

Question 35

Lad = left ascending artery: also known as?

Answer 35

Widowmaker

Question 36

In coronary artery disease, if LAD blocked, what effect does this have?

Answer 36

Means that not enough oxygen and nutrients get to left side of heart → heart can't contract property → heart attack

Question 37

Define cardiac output CO

Answer 37

Volume of blood expelled from LV at each beat

Question 38

Define ejection fraction EF

Answer 38

% Blood expelled from (left) ventricle at each beat

Question 39

Normal EF value =

Answer 39

60%

Question 40

Why is EF 60%?

Answer 40

Because you can't have complete closure of the ventricles Will be difficult to open up again

Question 41

How is EF calculated?

Answer 41

Difference between diastolic and systolic volume

Question 42

Initiating region for electrical impulse =

Answer 42

SAN

Question 43

Delay node to enable ventricular filling?

Answer 43

AVN node

Question 44

Bundle branches: function

Answer 44

Electrical conductance pathways through left and right myocardium, include bundle of HIS

Question 45

Specialised cardiac myocyte-like cells that are responsible for translating electrical impulse into contractile force?

Answer 45

Purkinje fibres

Question 46

Delay node is?

Answer 46

AV node

Question 47

P wave in Cardiac cycle shows?

Answer 47

Atrial depolarisation

Question 48

QRS complex in Cardiac cycle shows?

Answer 48

Ventricular depolarisation

Question 49

T wave in Cardiac cycle shows?

Answer 49

Ventricular repolarisation

Question 50

Volume of blood pumped by one ventricle per minute?

Answer 50

Cardiac output

Question 51

CO equation

Answer 51

CO = Heart rate X stroke volume ml/min (Beats/min). (ml/beat)

Question 52

Effects of exercise on CO

Answer 52

Increased venous return → increased stroke volume → increased cardiac output Preload is greater → cardiac muscle contracts with greater force