Lecture 47 - Cardiovascular System 1

Question 0

What is the origin of the diaphragm?

Where is the insertion?

Answer 0

The circumference - ie all the way around

The insertion is in the centre of the diaphragm

Question 1

What does the pericardium attach to?

Answer 1

The diaphragm insertion

Central tendon of the diaphragm

Question 2

Describe the orientation of the muscle fibres in the diaphragm

Answer 2

Muscle fibres go towards the centre from the circumferential diaphragm

Question 3

What limits diaphragmatic descent?

Answer 3

The heart and the vessels that are attached

Question 4

What is the pericardium made of?

Answer 4

External: Outer fibrous pericardium

Internal: serous pericardium (single layer of serous membrane)

Question 5

What do we always see in vista that expand and contract

Answer 5

A single layer of serous membrane lining the surface and the surface of the viscus

• parietal
• serous

Friction free

Question 6

What lies between the parietal and visceral serous membranes?

Answer 6

Pericardial cavity

Contains serous fluid

Question 7

Describe the path cutting through the pericardium

Answer 7

Fibrous pericardium
Parietal serous membrane
Pericardial cavity
Visceral serous membrane
Viscus

Question 8

What do we see on the anterior aspect of the heart?

Answer 8

Right sided chambers
On the right side: right atrium
On the left side: right ventricle

Also, a little bit of the left ventricle on the left border

Question 9

Why are the right chambers present on the anterior surface?

Answer 9

Rotation of the heart during development

Question 10

How do we differentiate the right atrium and ventricle externally?

Answer 10

Sulci

Anterior AV sulcus

Coronary sulcus

Question 11

How do we differentiate the right and left ventricles externally?

Answer 11

Sulcus

Anterior interventricular sulcus

Question 12

Where is the apex of the heart?

What is it made up of?

Answer 12

Anterior aspect

Right and left ventricles

Question 13

What are we feeling, when we feel our heart beat externally?

Answer 13

Apex of the heart beating against the anterior chest wall in the fifth intercostal space

Mid-Clavicular line, then drop down to the fifth intercostal space

Question 14

Where is the base of the heart?

Answer 14

At the top

Where all he vessels emerge

Question 15

How do we differentiate the left atrium and ventricle externally?

Answer 15

Coronary sulcus

Posterior aspect of heart

Question 16

Where does blood come from that enters the right atrium?

How does this affect the structure

Answer 16

It is a receiving chamber:
Receives blood from the vena cavae

Thin muscle wall

Question 17

What is present on the anterior interior surface of the right atrium?

Answer 17

Musculi pectinati

Muscular ridges

Question 18

Describe the posterior internal wall of the right atrium

Answer 18

Sinus venarum

Smooth

Question 19

Do the musculi pectinati slowly wave towards the back?

Answer 19

No, abruptly stop.

This is the:
Crista terminalis

Question 20

What is the name of the posterior wall of the right atrium?

What is on the other side?

Answer 20

Interatrial septum

Connects with the left atrium

Question 21

The right atrium receives blood from:

Answer 21

The entire body apart from the blood itself

Question 22

Are there valves in the vena cavae?

Answer 22

Superior VC: no, drops in from above

Inferior VC: rudimentary valve

Question 23

What does the IVC carry?

Answer 23

Blood from everything below the diaphragm

Question 24

Where does blood from the heart enter the right atrium?

Answer 24

Coronary sinus On the smooth posterior wall (sinus venarum) Between IVC and tricuspid valve

Question 25

Whee does blood flow from the right atrium in a foetus?

Answer 25

From right atrium to left atrium through the: foramen ovali Saves going through the lungs

Question 26

What happens to the foramen ovali after birth?

Answer 26

Flap comes over, forming Fossa ovali Seen as a pit

Question 27

Which valve separates the right atrium and right ventricle

Answer 27

The tricuspid valve

Question 28

How do we distinguish the posterior and anterior aspect of the heart

Answer 28

Atrial appendages (auricles) are both on the anterior surface of the heart, near the bottom of the great vessels

Question 29

Describe the muscle wall in the ventricle

Answer 29

Much thicker muscle than atrium

Question 30

Where does blood go from the right ventricle? What guards this flow?

Answer 30

Into the pulmonary artery Pulmonary valve

Question 31

Describe the surface of the interior walls of the right ventricle

Answer 31

Trabeculae carnae all the way around Except just below the pulmonary valve: - Conus arteriosus - Or Infundibulum

Question 32

Give an analogy of the surface of the right ventricle

Answer 32

Like bookshelves running along the wall Apart from three shelves These start on the wall and come out into the ventricle, called papillary muscle

Question 33

Where are the papillary muscles?

Answer 33

Right ventricle Start on interior wall and project into the centre of the cavity, to the Chordate tendinae

Question 34

What do the chordae tendinae connect to?

Answer 34

Papillary muscle | Tricuspid valve

Question 35

Describe the muscle and surface of the left ventricle wall

Answer 35

Thickest muscle wall Trabeculae carnae

Question 36

What is the valve between the left atrium and ventricle?

Answer 36

Mitral valve Only two cuspids

Question 37

How many papillary muscles in the left and right ventricles?

Answer 37

Left: two Right: three

Question 38

Describe the surface and muscle of the left atrium

Answer 38

Thin muscle wall Smooth Apart from the auricle going around to the anterior surface

Question 39

Why are the atria thin walled?

Answer 39

Because they are receiving chambers

Question 40

Where is the blood coming from, that comes into the left atrium?

Answer 40

The lungs Pulmonary vein

Question 41

What plane does the fibrous skeleton lie in? What does this mean?

Answer 41

Sagittal plane The muscle of the atria and ventricles are electically isolated

Question 42

Why have a fibrous skeleton?

Answer 42

* Anchors atrial and ventricle muscle: separated electrically * Attachment for base of valve cusp

Question 43

What attaches to the fibrous skeleton?

Answer 43

The mitral and tricuspid valves

Question 44

Where are the coronets?

Answer 44

Surround the semi-lunar valves

Question 45

Compare the atrial and ventricular surfaces of the cusps of the valves

Answer 45

Ventricular: rough Atrial: smooth

Question 46

What causes the atrioventricular valves to open and close? Describe the flow from Atrium to ventricle

Answer 46

Passive process Opening: pressure of blood in the atrium opens the lungs Then, flow from high pressure to low pressure from atrium into the ventricle Closing: slam shut when blood has flowed in

Question 47

What causes opening and closing of the pulmonary and aortic valves?

Answer 47

High pressure of blood due to the contraction of the ventricular muscle pushes the cusps up and to the side Slam shut when pressure drops

Question 48

What prevents blood flowing back into the atria when the ventricles contract?

Answer 48

The chordae tendinae fold the AV valves from opening

Question 49

How are the valves in the aorta and pulmonary trunk different from AV valves?

Answer 49

They are semilunar valves

Question 50

Describe the cusp attachments of the semilunar valves

Answer 50

Cusps supported by the two fibrous coronets The cusps attach to the very start of the pulmonary trunk and aorta

Question 51

Where are the origins of the coronary arteries?

Answer 51

At the very base of the aorta Just after the aortic valve

Question 52

Where is the SA node located?

Answer 52

At the top of the crista terminalis | Near opening of SVC

Question 53

What does the SA node do?

Answer 53

Generates an electrical impulse that spreads throughout the atrium, causing contraction of the artium

Question 54

What happens to the electrical conductance at the crista terminalis?

Answer 54

Stops, due to fibrous skeleton

Question 55

Where does the electrical impulse that goes through the ventricle originate? Where is it located?

Answer 55

AV node Situated at the fibrous skeleton

Question 56

How is the impulse conducted through the ventricles?

Answer 56

Specialised tissue: | Bundle of His

Question 57

Describe the general innervation of the heart Where is it?

Answer 57

Parasympathetic and sympathetic Cardiac Plexus at the base of the heart