The circulatory system consists of the cardiovascular and lymph vascular systems. The cardiovascular system includes the heart and blood vessels. The heart is a four-chambered organ made of three layers that pumps blood through two circuits: pulmonary circulation to the lungs and systemic circulation to the rest of the body. Heart failure occurs when the heart can no longer pump enough blood to meet the body's needs and can be caused by conditions like coronary heart disease, high blood pressure, cardiomyopathy, arrhythmias, or heart valve problems.

1. CIRCULATORY SYSTEM
BS-HND
DR. HIRA MUSTAFA
LECTURER
SFAS-502

2. Learning objectives:
 Anatomy of heart
 Diseases associated with heart

3. Introduction
 The circulatory system also called vascular system consists of two major
divisions:
1. Cardiovascular system
2. Lymph vascular system
 The human body has natural tendency to maintain its internal environment
within normal limits=> HOMEOSTASIS
 Maintenance of homeostasis is mainly done by
 Endocrine system
 Nervous system
 Circulatory system

4. Cardiovascular system
 Anatomically, this system consists
of
 Heart, which is pumping organ
 Blood vessels, which are pipelines
through which blood is
channeled to all parts of body

5. The Heart
 The heart is four-chambered pumping organ of the
cardiovascular system.
 It is cone-shaped, hollow, muscular organ located in
the thoracic cavity.
 There are two atria at the base of the heart and two
ventricles towards the apex.
 Atria= Receiving chambers for blood
 Ventricles= Pump the blood out of heart
 Function: To pump blood to different parts of the
body

6. Structure of the heart wall
 The heart wall consists of the following layers:
 Endocardium, the inner layer
It consists of endothelium, special variety of
epithelium that lines heart and blood vessels, beneath
it, a thin layer of C.T is present.
 Myocardium, the middle layer
Consists of very thick layer of striated muscle called
cardiac muscle.
 Epicardium, the outer layer
It consists of an external lining of simple squamous
epithelium.

7. Right heart
 The right heart consists of right atrium and right ventricle. The right atrium
receives deoxygenated blood through the superior and inferior vena cava and
the veins draining the heart wall.
 From the right atrium the blood passes into the right ventricle through the
right atrioventricular valve which is guarded by the tricuspid valve.
 The right ventricle pumps this blood into the pulmonary trunk, which
bifurcates into pulmonary arteries and deliver the blood to the lungs.

8. Left heart
 It consists of left atrium and left ventricle. The left atrium receives
oxygenated blood from lung by way of pulmonary veins.
 From the left atrium, this blood passes into left ventricle through the left
atrioventricular orifice which is guarded by mitral or bicuspid valve.
 Contraction of left ventricle propels the blood into the aorta
 From aorta blood is distributed throughout the body

10. Valves of heart
 The mitral valve is located on the left side of the heart, between the left
atrium and the left ventricle. This valve has two leaflets that allow blood to
flow from the lungs to the heart.
 The tricuspid valve is located on the right side of the heart, between the right
atrium and the right ventricle. This valve has three leaflets and its function is
to prevent blood from leaking back into the right atrium.
 Heart valve problems may include:
• Regurgitation (also called insufficiency) - In this condition, the valve leaflets
don’t close properly, causing blood to leak backward in your heart
• Stenosis - In valve stenosis, your valve leaflets become thick or stiff, and do not
open wide enough. This reduces blood flow through the valve.

11.  The aortic and pulmonic valves are known as the semilunar
 Pulmonary valve: This valve also has three leaflets. They allow
to pump from the right ventricle to the pulmonary artery. This
leads to the lungs, where blood picks up oxygen. The pulmonary
valve prevents blood from going backward from the pulmonary
to the right ventricle.
 Aortic valve: This valve has three leaflets. They open to let blood
from heart’s left ventricle to the aorta. The aorta is the largest
vessel in the body. It brings oxygenated blood from heart to the
of body. The aortic valve prevents backward flow from the aorta
the left ventricle.

13. Pulmonary and systemic circulation
 Pulmonary circulation moves blood between the heart and the lungs.
It transports deoxygenated blood to the lungs to absorb oxygen and release
carbon dioxide. The oxygenated blood then flows back to the heart.
 Systemic circulation moves blood between the heart and the rest of the body.
It sends oxygenated blood out to cells and returns deoxygenated blood to the
heart.

15. Heart failure

16. Heart failure
 Heart failure is a long-term condition in which heart can't pump blood well enough to meet
your body's needs all the time.
 Coronary heart disease – where the arteries that supply blood to the heart become clogged
up with fatty substances (atherosclerosis)
 High blood pressure – this can put extra strain on the heart, which over time can lead to
heart failure
 Conditions affecting the heart muscle (cardiomyopathy)
 Heart rhythm problems (arrhythmias)
 Damage or other problems with the heart valves
 Congenital heart disease – birth defects that affect the normal workings of the heart
 Sometimes obesity, anemia, drinking too much alcohol can also lead to heart failure.