The heart has 3 layers, 4 chambers, and 4 valves. It is located in the thoracic cavity and pumps oxygenated blood to the organs and tissues while removing waste. The cardiovascular system includes pulmonary circulation to oxygenate blood in the lungs and systemic circulation to deliver oxygenated blood throughout the body. The heart's conduction system uses sinoatrial and atrioventricular nodes and Purkinje fibers to control the heartbeat and ensure blood flows in one direction through the cardiac cycle.

1. The Heart

2. • Define the function of the heart
• Identify the different layers of the heart and their function
• Identify the chambers of the heart
• Understand the function of the valves of the heart
• Understand blood flow and the cardiac cycle
• Understand the conducting system of the heart

3. Location
• The heart is located in the
thoracic cavity
• Posterior to the sternum
• Superior to the diaphragm
• Between the lungs
• The tip of the heart is called
the ‘apex’
BASE
APEX
Image source – See slide 28

4. Anatomy
The heart has:
3 layers
• pericardium
• endocardium
• myocardium
4 chambers
• 2 atrium
• 2 ventricles
4 valves
• Mitral
• Aortic
• Tricuspid
• Pulmonary
Image source – See slide 28

5. Function
• The heart pumps oxygen and nutrient
rich blood to the organs, tissues and
cells of the body, and eliminates
waste products
Image source – See slide 28

6. • Blood is carried from the heart
to the organs through arteries,
arterioles and capillaries
• Blood returns to the heart
through venules and veins
Function
Image source – See slide 28

7. Layers of the Heart
Pericardium:
The heart is surrounded by a fibro serous
sac called the pericardium
The function of the pericardium is:
• To limit cardiac distension and restrict
excessive movement
• To protect and lubricate
The pericardium is composed of:
• Visceral pericardium
• Parietal pericardium
• Pericardial cavity
Image source – See slide 28

8. Endocardium:
• Innermost/deepest layer of the heart
• Lines the heart chambers and the valves
• Smooth thin lining to reduce friction of
blood flow through the chambers
• Cardiac conduction system located in this
layer
Layers of the Heart
Image source – See slide 28

9. Myocardium:
• Middle, thickest layer
of the heart
• Contains the muscle fibres
which are responsible for
pumping
• Contraction of this layer
allows blood to be pumped
through to the blood vessels
Layers of the Heart
Image source – See slide 28

10. Chambers of the Heart
he heart is divided into four
chambers:
A: Right Atrium
V: Right Ventricle
A: Left Atrium
V: Left Ventricle
Image source – See slide 28

11. Upper Chambers
The upper chambers are:
• The atria
- Right
- Left
Image source – See slide 28

12. The right atrium:
Receives deoxygenated blood from
the body through the:
• superior vena cava (head and
upper body)
• inferior vena cava (legs and lower
torso)
The left atrium:
Receives oxygenated blood from the
lungs through the:
• pulmonary vein
Upper Chambers
Image source – See slide 28

13. Lower Chambers
The lower chambers are:
• The ventricles
– Right
– Left
Image source – See slide 28

14. The right ventricle:
Receives de-oxygenated blood
as the right atrium contracts
The left ventricle:
Receives oxygenated blood
as the left atrium
contracts
Lower Chambers
LV
RV

15. Valves of the heart
he valves are located within
the chambers of the heart.
he function of the valves:
ontrols the direction of
blood flow
llows one way flow of blood
- through chambers
- from the heart to the body Image source – See slide 28

16. Valves of the heart
The four valves are known as:
• the tricuspid valve
• the pulmonic or pulmonary valve
• the mitral valve
• the aortic valve
Image source – See slide 28

17. The tricuspid valve:
• Is an atrioventricular valve,
situated between the atria and the
ventricle
• Controls the opening between the
right atrium and the right ventricle
The mitral valve:
• Is an atrioventricular valve,
situated between the atria and the
ventricle
• Controls the blood between the
left atrium and the left ventricle
Valves of the heart
Image source – See slide 28

18. The pulmonic or pulmonary valve:
• Is a semi lunar valve which controls
the blood leaving the heart
• Situated between the right ventricle
and the pulmonary valve
• Controls the flow of blood from the
right ventricle
• Prevents blood flow back to the
right ventricle, as it relaxes
Valves of the heart
Image source – See slide 28

19. The aortic valve:
• Is a semi lunar valve which
controls the blood leaving the
heart
• Controls blood flow between
the left atrium and the aorta
Valves of the heart
Image source – See slide 28

20. The Cardiovascular system
he Cardiovascular System consists of the:
eart
ungs
lood vessels
t includes:
ulmonary circulation
ystemic circulation
Image source – See slide 28

21. Pulmonary circulation
ulmonary circulation is:
he carriage of oxygen-depleted blood away
from the heart to the lungs via the pulmonary
artery
he return of oxygen-rich blood to the heart
via the pulmonary vein
Image source – See slide 28

22. ulmonary circulation and the heart
he inferior and superior vena cava carry oxygen depleted blood to the relaxed right atrium of
the heart
he right atrium contracts and blood travels through the tricuspid valve into the relaxed right
ventricle
he right ventricle contracts, the blood is pumped through the pulmonary valve into the
pulmonary artery to the lungs
as exchange occurs in the lungs
o2 is released and oxygen is absorbed
Pulmonary circulation

23. Systemic circulation
Systemic circulation is:
• The carriage of oxygen-rich blood
away from the heart to the body
• The return of oxygen-depleted blood
back to the heart
Image source – See slide 28

24. Systemic circulation and the heart
• Oxygen rich blood travels from the lungs via the pulmonary veins to the left
atrium
• The left atrium contracts, and blood flows through the mitral valve into the
relaxed left ventricle
• The strong left ventricle contracts and pumps oxygen rich blood through the
aortic valve into the aorta
• The aorta carries blood to the organs of the body
Systemic circulation

25. The Conducting system
ardiac conduction is:
he rate the heart conducts electrical
impulses
he electrical pulses determine the
order in which the chambers contract:
the heart rate
he path the impulses travel: Image source – See slide 28

26. The Conducting system
he Sinoatrial node (SA) :
s also known as the pace maker of the
heart
he Sinoatrial node is:
ocated in the upper wall of the right
atrium
ade up of nodal tissue - both muscle
and nervous tissue
here the electrical impulse begins
Image source – See slide 28

27. The Conducting system
he Atrioventricular (AV) node:
s located between the atria and
ventricles of the heart
ade up of nodal tissue
he electrical impulse is carried from the
SA node, and the AV node is
stimulated.
he AV node delays the path of the Image source – See slide 28

28. The Conducting system
Atrioventricular bundle branches:
• are located between the atria and
the ventricles.
• Fibres branch into two bundles -left
and right side of the heart
The electrical impulse travels from the
AV node to the bundle branches
after the atria have contracted and
emptied.
The AV bundle branches then carry the
impulses down the centre of the
heart to the left and right ventricles
Image source – See slide 28

29. The Conducting system
he AV bundles start to divide
further into:
urkinje fibres
urkinje fibres:
ocated at the end of the AV bundle
branches, at the base of the heart
he Purkinje fibres are responsible for
the contraction of the ventricles
Image source – See slide 28

30. 1. Arch of aorta
2. Superior vena cava
3. Pulmonary artery
4. Pulmonary veins
5. Right atrium
6. Tricuspid valve
7. Right ventricle
8. Inferior vena cava
9. Pulmonary artery
10. Pulmonary veins
11. Left atrium
12. Mitral valve
13. Aortic valve
14. Left ventricle
15. Descending aorta
Anatomy - Overview
Image source – See slide 28

31. • The heart is located in the thoracic cavity
• The heart has: 3 layers, 4 chambers, 4 valves
• The heart pumps oxygen and nutrient rich blood to the organs, tissues and cells of the
body, and eliminates waste products
• The Cardiovascular System: Pulmonary circulation, Systemic circulation, Coronary
circulation
• Cardiac conduction is: the rate the heart conducts electrical impulses
• The path the impulses travel: Sinoatrial node (SA node), Atrioventricular node (AV node),
Bundle branches, Purkinge fibres: the heart rate
A summary

32. Image sources
Slide 3
http://www.bem.fi/book/06/06.htm
Slide 4
top:
http://www.nuclearcardiologyseminars.net/structure.htm
bottom:
http://www.texasheartinstitute.org/hic/anatomy/anatomy2.cfm
Slide 5
http://www.thewellingtoncardiacservices.com/the-heart-cardiovascular-system
Slide 6, 12
http://www.texasheartinstitute.org/hic/anatomy/anatomy2.cfm
Slide 7
http://apbrwww5.apsu.edu/thompsonj/Anatomy%20&%20Physiology/2020/2020%20Exam%20Reviews/Exam%201/CH18%20Pericardial%20Cavity%20and%
Slide 8
http://www.courseweb.uottawa.ca/medicine-histology/english/cardiovascular/Fig08_Cardiovascular.htm
Slide 9
http://webhome.broward.edu/~jlarson/WebCT_6/Instructional_Design/12Leads/05.htm
Slide 10
http://www.skillstat.com/heartscape/chambers.htm
Slide 11, 13
http://www.starsandseas.com/SAS%20Physiology/Cardiovascular/Cardiovascular.htm
Slide 15,16
http://nyp.org/health/cardiac-valves.html
Slide 17
http://www.texasheartinstitute.org/hic/topics/cond/valvedis.cfm
Slide 18 - As per copyrighted
Slide 19
http://www.tutorvista.com/content/biology/biology-iv/circulation-animals/comp
Slide 20
http://revisionworld.co.uk/a2-level-level-revision/biology/physiology-transport/
Slide 21
http://en.wikipedia.org/wiki/Pulmonary_artery
Slide 23
http://www.prevent-stroke-and-heart-attack.com/pulmonary-and-
systemic-circulation.html
Slide 25
http://biology.about.com/library/organs/heart/blcardiacconduction.htm
Slide 26
http://hyperphysics.phy-astr.gsu.edu/hbase/biology/sanode.html
Slide 27, 28, 29
http://www.tutorvista.com/content/biology/biology-iv/circulation-
animals/blood-circulation-mammalian-heart.php
Slide 30
http://sjesci.wikispaces.com/Heart+and+Lungs
References:
Drake, Richard L., Vogl, Wayne. A, Mitchell, Adam W.M., Grays
Anatomy for Students, Second Edition, Churchill Livingstone