Objectives
• Label the layers, chambers, valves & major blood
vessels on a diagram of the heart.
•Differentiate between what happens in the heart
during each phase
•List the three major types of blood vessels and the
action of each type.
•Compare the three main blood cells by describing
the function of each type.
•Describe at least five diseases of the circulatory
system.
•Circulatory system also known
as the cardiovascular system.
•Consists of the heart, blood
vessels, and blood.
•Often referred to as the
transportation system of the
body.
- Transports oxygen and
nutrients to body cells
- Transports carbon dioxide
and metabolic materials away
from body cells.
•Muscular, hollow organ
•Often called the pump of
the body
•About the size of a
closed fist
•Located in the
mediastinal cavity,
between the lungs,
behind the sternum, and
above the diaphragm.
• Muscular
wall
•Separates the heart into a right
and left side
•Prevents blood from moving
between the right and left side of
the heart.
•Upper part of the septum called
interatrial septum
•Lower part called the
interventricular septum.
• Heart is divided into four parts
or chambers
•Two upper chambers are called
atria
•Two lower chambers are called
ventricles
•Right atrium receives blood as
it returns from body cells
• Right Ventricle
- Receives blood from right atrium
-Pushes the blood into the pulmonary artery , which carries the
blood to the lungs for oxygen
•Left atrium receives oxygenated blood from the lungs
•Left ventricle
-Receives blood from the left atrium
-Pushes blood into the aorta so it can be carried to body cells.
• One-way valves in the
chambers of the heart keep
the blood flowing in the
right direction.
•Tricuspid Valve-Located between the right
atrium and the right
ventricle
-Closes when the right
ventricle contracts and
pushes blood to the lungs
-Prevents blood from
flowing back into the right
atrium
•Located between the right ventricle
and pulmonary artery, a blood vessel
that carries blood to the lungs.
•Closes when the right ventricle has
finished contracting and pushing
blood into the pulmonary artery.
•Prevents blood from flowing back
into the right ventricle.
• Located between the left atrium and left
ventricle
•Closes when the left ventricle is contracting
and pushing blood into the aorta so it can be
carried to the body.
•Prevents blood from flowing back into left
atrium.
• Located between the left
ventricle and aorta, the largest
artery in the body.
•Closes when the left ventricle
is finished contracting and
pushing blood into the aorta.
•Prevents blood from flowing
back into the left ventricle.
a. Right and left sides of the heart
work together in a cyclic
manner even though they are
separated by the septum.
b. Electrical impulse originating in
the heart causes the
myocardium to contract in a
cyclic manner
c. Cycle consists of a brief period
of rest called diastole followed
by a period of ventricular
contraction called systole
d. At start of the cycle, atria
contract and push blood into
the ventricles.
e. Then atria relax
f. Blood returning from the body
enters the right atrium/
g. Blood returning from the
lungs enters the left atrium.
h. While atria are filling, systole
begins and the ventricles
contract.
i. Right ventricle
pushes blood into the
pulmonary artery so
it can go to the lungs
for oxygen.
j. Left ventricle pushes
blood into the aorta
so it can be carried to
all parts of the body.
k. Blood in the right
side of the heart is
low in oxygen and
high in carbon
dioxide.
l. When it gets to the lungs,
the carbon dioxide is
released into the lungs and
oxygen is taken into the
blood.
m. Oxygenated blood is then
carried to the left side of
the heart by the
pulmonary veins.
n. Now the blood in the left
side of the heart is high in
oxygen and low in carbon
dioxide and ready to be
carried to body cells.
1. Electrical impulses originating in the heart cause the cyclic
contraction of the muscles.
2. Starts in the sinoatrial (SA) node
a. Group of nerve cells located in the right atrium.
b. Also called the pacemaker.
c. Sends out an electrical impulse that spreads out over the
muscles in the atria.
d. Atrial muscles then contract and push blood into the ventricles
e. After electrical impulse passes through the atria, it reaches the
atrioventricular (AV) node.
3. Atrioventricular (AV) node
a. Group of nerve cells located between the atria and
ventricles.
b. AV node sends electrical impulse through nerve
fibers in the septum called the bundle of His.
4. Bundle of His
a. Nerve fibers in septum
b. Divides into a right and left bundle branch
5. Right and left bundle branches.
a. Pathways that carry the impulse down through the ventricles.
b. Bundles continue to subdivide into a network of nerve fibers
throughout the ventricles called Purkinje fibers.
6. Purkinje fibers
a. Final fibers on conduction pathway.
b. Spread electrical impulse to all of the muscle tissue in the
ventricles.
c. Ventricles then contract.
7. Electrical conduction pattern occurs approximately
every 0.8 seconds.
8. Movement of the electrical impulse can be recorded
on an electrocardiogram (ECG or EKG) and used to
detect abnormal activity or disease.
1 The SA
node sets
the rate
and rhythm
of your
heartbeat
2
The SA node fires
an impulse. The
impulse spreads
through the walls
of the right and
left atria, causing
them to contract.
This forces blood
into the ventricles.
3 The impulse
travels to the AV
node. Here, the
impulse slows
for a moment
before going on
to the ventricles
.
4 The impulse travels
through a pathway of
fibers called the HISPurkinje network. This
network sends the
impulse into the
ventricles and causes
them to contract. This
forces blood out of the
heart to the lungs and
body.
5 The SA node
fires another
impulse.
The cycle begins
again
.
a. Carry blood away from the heart.
b. Aorta
1. Largest artery in the body
2. Receives blood from the left ventricle of the
heart.
3. Immediately begins branching into smaller
arteries.
c. Arterioles
1. Smallest branches of arteries.
2. Join with capillaries.
d. Arteries are more muscular and elastic than
the other blood vessels because they receive
the blood as it is pumped from the heart.
a. Connect arterioles with
venules, the smallest veins.
b. Have thin walls that contain
only one layer of cells
c. Allow oxygen and nutrients
to pass through to the cells.
d. At the same time, carbon
dioxide and metabolic
products from the cells enter
the capillaries.
a. Blood vessels that
carry blood back to
the heart
b. Venules
1. Smallest branches
of veins
2. Connect with the
capillaries
3. Venules join
together and
become larger to
form veins
1. Two largest veins
2. Superior vena cava brings the
blood from the upper part of the
body.
3. Inferior vena cava brings the
blood from the lower part of the
body.
4. Both vena cava drain into the
right atrium.
d. Veins are thinner than arteries
and have less muscle tissue.
e. Most contain valves that keep
the blood from flowing in a
backward direction.
1. Blood often called a tissue
because it contains many
kinds of cells.
2. About four to six quarts of
blood in the average adult.
3. Blood circulates throughout
the body continually
4. Transports many substances
a. Oxygen from the lungs to body cells
b. Carbon dioxide from body cells to the lungs
c. Nutrients from the digestive tract to cells.
d. Metabolic waste products from cells to the organs of excretion.
e. Heat produced by various body parts
f.
Hormones produced by endocrine glands to the organs in the body.
a.
Fluid or liquid portion of blood
b. About 90% water
c.
Many substances dissolved or
suspended in the water.
1.
Blood proteins such as fibrinogen
and prothrombin , necessary for
clotting.
2.
Nutrients such as carbohydrates
and proteins.
3.
Mineral salts
4.
Electrolytes such as potassium,
calcium, and sodium
5.
Gases such as carbon dioxide and
oxygen
6.
Metabolic and waste products
7.
Hormones
8.
Enzymes
a. Solid elements of blood.
b. Three main kinds of blood
cells or corpuscles:
erythrocytes, leukocytes,
and thrombocytes
c. Erythrocytes or red blood
cells.
1. Produced in the red bone
marrow at a rate of about
one million per minute.
2.
Live about 120 days before
being broken down by the
liver and spleen.
3. Four and a half to five and a half million erythrocytes per cubic
millimeter of blood ( approximately one drop of blood), or 25
trillion in body
4. Mature form circulating in the blood does not have a nucleus and
is shaped like a disc with a thinner central area.
5. Contain a complex protein called hemoglobin
aa. Composed of protein molecule called globin and an iron
compound called heme
bb. Carries both oxygen and carbon dioxide
cc. When hemoglobin carries oxygen and carbon dioxide.
dd. If blood contains a lot of oxygen, it is bright red.
ee. When there is less oxygen and more carbon dioxide, it is a much
darker red.
A.K.A White blood cells
•
Not as numerous as erythrocytes
•
Formed in the bone marrow and
lymph tissue and usually live about
3-9 days.
•
Normal count is five to ten thousand
leukocytes per cubic millimeter of
blood.
•
Leukocytes can pass through
capillary walls and enter body
tissue.
5. Main function is to fight infection.
6. Phagocytosis.: process by which some leukocytes engulf, ingest
and destroy pathogens or germs.
7. Five types of Leukocytes
aa. Neutrophils: phagocytize bacteria
bb. Eosinophils: remove toxins and defend body from allergic
reactions.
cc. Basophils: Participate in body’s inflammatory response; produce
histamine , a vasodilator, and heparin , an anticoagulant.
dd. Monocytes: Phagocytize bacteria and foreign materials
ee. Lymphocytes: Provide immunity for the body by developing
antibodies; protect against formation of cancer cells.
1)not as numerous as erythrocytes
2)formed in the bone marrow and lymph
tissue and usually live about 3 to 9 days
3)normal count is five to ten thousands
leukocytes per cubic millimeter of blood
4)leukocytes can pass through capillary walls
and enter body tissue
5)main function is to fight infection
6)phagocytosis:process by which some
leukocytes engulf, ingest, and destroy
pathogens or germs
7)five types of leukocytes
aa.neutrophils: phagocytize bacteria
eosinophils
basophils
monocytes
lymphocytes
• provide
immunity for
the body by
developing
antibodies;
protect
against the
formation of
cancer cells.
•Phagocytize
bacteria and foreign
materials.
• remove toxins
& defend body
from allergic
reactions
•phagocytize
bacteria
1. Also called platelets
2. Usually described as fragments or pieces of cells.
3. Do not have a nucleus
4. Vary in shape and size.
5. Formed in bone marrow and live about 5-9 days.
6. Important for the clotting process which stops bleeding.
aa. When a blood vessel is cut, thrombocytes collect at the site to
form a sticky plug.
bb. They secrete a chemical, serotonin, which causes the blood
vessel to spasm and narrow, decreasing the flow of blood.
cc. Also release an enzyme, thromboplastin, which acts with
calcium and other substances in the plasma to form thrombin.
dd. Thrombin acts on the blood protein fibrinogen to form fibrin, a gel-like
net of fine fibers that traps erythrocytes, platelets, and plasma to form
a clot.
ee. Effective method for controlling bleeding in smaller blood vessels.
ff. If a large blood vessel is cut, the rapid flow of blood can interfere with
the formation of fibrin.
gg. Doctor may have to insert sutures ( stitches) to close the opening and
control the bleeding.
7. Normal-250,000-400,000 per cubic mm of blood.
• also called
platelets.
Important for
blood clotting.
•Normal count is
250,000 to
400,000 per
cubic millimeter
of blood.
Diseases and abnormal
conditions
Anemia
• Inadequate number of
erythrocytes, hemoglobin or
both
• Symptoms pallor or paleness,
fatigue, dyspnea, rapid heart
rate
• Acute blood loss anemia
• Caused by hemorrhage or
rapid blood loss
• Corrected by transfusions of
blood.
• Iron Deficiency anemia
•Caused by inadequate
amount of iron to form
hemoglobin in
erythrocytes
•Treatment: iron
supplements and
increased iron intake
from green leafy
vegetables and other
foods.
• Aplastic Anemia
•Caused by injury or
destruction of bone marrow.
•Results in poor or no
formation of erythrocytes.
•Fatal unless damage can be
reversed
• Pernicious anemia
•Caused by lack of intrinsic
factor, which results in poor
absorption of vitamin B12
•Results in formation of
inadequate and abnormally large
erythrocytes.
•Treatment: replacing intrinsic
factor and administering b 12
injections.
Sickle Cell Anemia
• Inadequate number of
erythrocytes,
hemoglobin, or both
• Caused by rapid blood
loss
• Corrected by
transfusion of blood
• Caused by inadequate
amount of iron to form
hemoglobin in
erythrocytes
Aneurysm
• Ballooning out or saclike formation on the wall
of the artery.
• A weakness in the wall of the artery through
which blood can break through causing
hemorrhage into surrounding spaces or tissues
•Some cause pain and pressure, some
have no symptoms
•If aneurysm ruptures it will cause
hemorrhage, can cause death
Aneurysm
•
•
Arteriosclerosis
• Hardening or
thickening of the
arteries.
• Loss of elasticity and
contractility.
• Commonly occurs as
a result of aging.
•
Atherosclerosis
• Atherosclerosis is the
process by which a plaque
composed mainly of lipids
or fats is deposited along
the inner walls of your
arteries. Many heart
diseases (such as
coronary heart disease)
are atherosclerotic, in that
the accumulation of
plaque within the arteries
is related to or is one of
the characteristics of the
condition.
Atherosclerosis
• Fatty plaques,
frequently
cholesterol, deposited
on walls of arteries.
• Causes narrowing if
opening, which
reduces or eliminates
the flow of blood.
•
•Atherosclerosis
Congestive Heart Failure
• Congestive heart failure
describes what happens
when the heart is unable
to pump enough blood
to the tissues. Tissues
that do not receive
enough oxygen to meet
their needs become
weakened, cannot
function properly, and
may eventually die.
Embolus
• Foreign substance in blood stream: air,
clot, bacteria, fat globule
• Blockage of vessel occurs when embolus
enters artery or capillary.
Hemophilia
• Inherited disease
• Occurs in males but
carried in females
• Blood not able to clot
due to lack of plasma
protein
• Minor cuts can lead to
prolonged bleeding
Hypertension
• People who suffer
from hypertension
have consistently high
blood pressure. The
effects of
hypertension can be
felt throughout the
entire cardiovascular
system, and people
with this disease are
at risk of damaging
their heart, kidneys,
eyes, and even their
brain.
Orthostatic Hypotension
• defined as a decrease of at
least 20 mm Hg in systolic
blood pressure when an
individual moves from a
supine position to a standing
position.
• Nonneurogenic causes of
orthostatic hypotension are
related to cardiac pump
failure, reduced
intravascular volume,
venous pooling or a
medication side effect.
Pulmonary Hypertension
• The narrowing of the
Pulmonary arterioles
within the lung.
• This causes resistance
and an increase work
load for the heart.
• The heart becomes
enlarged from pumping
blood against the
resistance.
•
• symptoms result from
the body not
producing enough
healthy blood cells.
• Healthy bone marrow
makes stem cells that
grow into the three
types of blood cells:
red blood cells, white
blood cells, and
platelets.
• An AML patient's
bone marrow makes
too many blast cells
(immature white
blood cells).
Acute Myelocytic Leukemia
• (cancer) of blood –
forming tissues of the
bone marrow
characterized by the
proliferation of
immature white
blood cells
Arrhythmias
• Disturbance in electrical conduction
resulting in abnormal heart rhythms
• Can be mild or life threatening- PAC
(premature atrial contraction) or ventricular
fibrillation
• Treatment- defibrillator or pacemaker
Myocardial Infarction
• A myocardial infarction is
another term for a heart
attack
• . A heart attack occurs
when sections of heart
muscle do not receive
enough oxygen, primarily
due to occluded
coronary arteries.
•Affected heart tissue dies
and is known as an infarct.
•A blockage in coronary
arteries cuts off the supply of
blood to the heart.
Varicose veins
• Dilated, swollen veins
that have lost
elasticity and cause a
stasis or decreased
blood flow.
• Treatment:
• Exercise and avoid
prolong sitting or
standing
•
Varicose Veins
Coronary Heart Disease
• When plaque or blood fragments are deposited
along the inside wall of the coronary arteries
(vessels that supply the heart muscle with blood),
these vessels may become occluded. Coronary
occlusion, which also may result from
atherosclerosis or coronary artery muscle spasm,
refers to the complete obstruction of the blood
vessel that prevents blood flow to the cells of the
heart. When the coronary arteries become
occluded, the result is the development of
coronary heart disease, also known as coronary
artery disease or ischemic heart disease.
Dementia
• a progressive brain dysfunction,
leads to a gradually increasing
restriction of daily activities. The
most well-known type of dementia
is Alzheimer's disease. Dementia
not only affects patients, but also
those surrounding them, as most
patients require care in the longterm.
Pulmonary Valve Stenosis
• A condition, usually
present at birth, in
which outflow of
blood from the right
ventricle of the heart
is obstructed at the
level of the pulmonic
valve (valve which
separates the heart
from the pulmonary
artery).
Continued….
• Pulmonary stenosis is
most often caused by
a malformation during
fetal development for
unknown reasons. A
narrowing may occur
in the pulmonary valve
or below the
pulmonary valve at the
pulmonary artery. The
defect may occur
alone, or with other
heart defects.
Mitral valve prolapse (MVP)
• Common condition in which cusps of mitral valve
prolapse into left atrium during systole
• Symptoms- nonanginal chest pain, palpitations,
dyspnea, fatigue- murmur at apex holosystolically
• Treatment- if mitral regurgitation is presentantibiotic prophylaxis indicated during surgical
and dental procedures
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