1. Anatomy and Physiology
of Cardiovascuar System
Presented by:
Haseeb Ahsan
Kashif Nazir
M. Hassan
Abdulwassay

2. Cardiovascular System:
It is an Organised system of inter connected vessels specialized
for transporting blood through out the body and removing
metabolic wastes from it.
It consists of following three components:
• Heart
• Blood vessels
• Blood

3. Anatomy of Human heart:
Human heart is hollow, muscular organ located in medial mediastinum.
It is some what pyramidal in shape, with apex directed downwards, forward
and to the left. Its base is direscted upwards. Major vessles arise from its
base.
Structure of heart:
Heart is divided in four chambers:
• Atria
• Ventricles
The heart consists of following layers (moving from outside to insde):
• Fibrous pericardium and serous pericardiam (Epicardiam)
• Myocardium
• Endocardiam
The skeleton of heart consists of fibrous rings that surrounds atrioventricular,
pulmonary and aortic orifices.

4. Atria:
These are thin walled chambers of heart whose function is to receive
blood from body.
Their myocardium is thin and eject blood with less pressure.
Both atria are present superiorly in the heart and separated by inter-
atrial septum.
Right atrium
The right atrium consists of the main caity called auricle and has followig openings:
• Opening of superior venacava
• Opening of inferior venacava
• Bicuspid valve that opens in to right ventricle
Left atrium:
The left atrium consists of the main cavity called auricle and following openings:
• The openings of pulmonary veins
• The tricuspid valve which opens in to left ventricle.

5. Ventricles:
These are thick walled chambers of heart present inferiorly in heart and
their function is to send blood to the body.
Their myocardium is thick and eject blood with greater pressure.
They are separated by interventricular septum.
Right ventricle:
The right ventricle consists of the main cavity called ventricle. The normal cross-
section of right ventricle is Crecent shaped and has following openings:
• The opening of tricuspid valve
• The opening of pulmonary valve that takes blood to lungs
Left ventricle:
The left ventricle consists of the main cavity called ventricle. It is cylindrical in shape
and has thickest myocardium of all chambers.
It has following openings:
• The opening of bicuspid or mitral valve
• The semilunar valve that takes blood to whole body via aorta

6. Conducting system of heart:
The conducting system of heart is composed of special cardiac muscles
which control the heart beat by generating and transmitting nerve impulse at
regular intervals.
Sino- Aterial Node:
The Sino-Aterial node is present at the top of right atrium it is also called pace-maker,
because it initiates the heart beat through nerve impulse.
Aterioventricular Node:
It is present in the lower part of aterial septum. From here the nerve impulse is transferred
to ventricular walls by bundle of His and purkinje plexus.
Nerve supply:
The heart is supplied by sympathetic and parasympathetic nerve supply from autonomic
nervous system via cardiac plexus.

8. Blood vessels:
The blood vessels are elastic tubes that trasport blood to all the body parts.
These are held in place in the body by facia.
There are three types of blood vessels namely:
• Arteries
• Capillaries
• Veins
Arteries:
These blood vessels tansport blood away from the heart.
All arteries carry oxygenated blood except pulmonary arteries.
There are no valves in them except at the base of pulmonary trunk and aorta.
The blood pressure is very high in them and pulse can be felt by palpating them.
These have small bore, thick walls and usually buried deep in the body.
The walls of arteries are made up of three layers:
• Tunica adventia (made up of connective tissue and elastic fibers)
• Tunica media ( made up of smooth muscles)
• Tunica intima (Made up of endothelium)

9. Veins:
These vessels collect blood from all over the body and carry blood towards the heart.
All veins carry deoxygenated blood except pulmonary vein.
The muscle layer and elastic layyer is thin and connective layer a bit thick.
Valves are present that prevent back flow of blood.
The blood pressure is low and no pulse can be felt by palpating them.
They have larger bore and thin walls.
The walls of arteries are made up of three layers:
• Tunica adventia (made up of connective tissue and elastic fibers)
• Tunica media ( made up of smooth muscles)
• Tunica intima (Made up of endothelium)
Capillaries:
These link the arteries and veins. These are formed by division of arteries and then
unite to form veins.
Some of them carry oxygenated and some carry deoxygenated blood.
The walls of capillaries are single cell thick and serve as the site of material
exchange.

11. Physiology of heart:
The heart is a strong muscualr organ specialised for pumping blood in the body. It
acts as a double pump pumping oxygenated blood to the body and deoxygenated
blood to the lungs for oxygenation, thus runs two types of circulations at the same
time namely:
• Systemic circulation
• Pulmonary circulation
Its functioning can be studied apropriatly by studying the cardic cycle.
The sequence of events that takes place during the completion of one heart beat
is called Cardiac cycle.
A complete cardiac cycle lasts for 0.8 seconds. A complete cardiac cycle makes
one heart beat, thus heart beats
It consists of two set of events.
• Atrial events
• Ventricular events

12. Atrial events:
The atrial events last for 0.8s and are further divided in to two
stages:
Atrial systole
The rapid contraction of atrial walls ejecting the blood from their
cavities in to the ventricles via atrioventricular valves is called
Atrial systole.
It lasts for 0.1second.
Atrial diastole
After immediate contraction there is a rest gap of 0.7 seconds it is
called arterial diastole. In this period the atria continue to fill up
with blood.

13. Ventricular events:
The ventricular events have duration of 0.8s and are further divided
in to two stages:
Ventricular systole:
The contraction of ventricles just after the atrial systole
ejecting the blood from ventricles through pulmonary and
semilunar valves is called ventricular systole.
It lasts for 0.3 seconds.
Ventricular diastole
The relaxation of ventricles after the ventricular systole is
called ventricular diastole and it lasts for 0.5s.
In ventricular systole the blood starts entering the ventricles

14. Composition and function of blood

16. Functions of Blood:
1-Blood Brings Waste Products to the Kidneys and Liver:

17. 2-Red Blood Cells Are the Most Numerous Living Cells in
Blood

18. 3-Blood Transports Nutrients and Hormones:

19. 4-Blood Regulates Body Temperature

20. 5-Blood Provides the Body's Cells with Oxygen and Removes Carbon
Dioxide.
6-Function of WBCs: