Download The_Circulatory_System - Miami Beach Senior High School

27-1
The Cardiovascular System
PowerPoint® presentation to accompany:
Medical Assisting
Third Edition
Booth, Whicker, Wyman, Pugh, Thompson
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-2
Learning Outcomes
27.1 Describe the structure of the heart and the
function of each part.
27.2 Trace the flow of blood through the heart.
27.3 List the most common heart sounds and what
events produce them.
27.4 Explain how heart rate is controlled by the
electrical conduction system of the heart.
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-3
Learning Outcomes (cont.)
27.5 List the different types of blood vessels and
describe the functions of each.
27.6 Define blood pressure and tell how it is
controlled.
27.7 Trace the flow of blood through the pulmonary
and systemic circulation.
27.8 List the major arteries and veins of the body and
describe their locations.
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-4
Learning Outcomes (cont.)
27.9 List and describe the components of blood.
27.10 Give the functions of red blood cells, the different
types of white blood cells, and platelets.
27.11 List the substances normally found in plasma.
27.12 Explain how bleeding is controlled.
27.13 Explain the differences among blood types A, B,
AB, and O.
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-5
Learning Outcomes (cont.)
27.14 Explain the difference between Rh-positive blood
and Rh-negative blood.
27.15 Explain the importance of blood typing and tell
which blood types are compatible.
27.16 Describe the causes, signs and symptoms, and
treatments of various diseases and disorders of
the cardiovascular system.
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-6
Introduction

The cardiovascular system consists of heart and
blood vessels

Sends blood to



Lungs for oxygen
Digestive system for nutrients
CV system also circulates waste products to
certain organ systems for removal from the blood
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-7
The Heart: Structures




Cone-shaped organ
about the size of a
loose fist
In the mediastinum
Extends from the level
of the second rib to
about the level of the
sixth rib
Slightly left of the
midline
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-8
The Heart: Structures (cont.)

Heart is bordered:




Laterally by the lungs
Posteriorly by the vertebral
column
Anteriorly by the sternum
Rests on the diaphragm
inferiorly
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-9
The Heart: Structures (cont.)

Heart coverings

Pericardium



Covers the heart and
large blood vessels
attached to the heart
Click for Larger View

Heart walls:

Epicardium


Outermost layer
Fat to cushion heart
Visceral pericardium

Innermost layer

Directly on the heart
Parietal pericardium

Layer on top of the
visceral pericardium

Myocardium



Middle layer
Primarily cardiac muscle
Endocardium



Innermost layer
Thin and smooth
Stretches as the heart
pumps
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-11
The Heart: Structures (cont.)

Four chambers
 Two atria




Upper chambers
Left and right
Separated by
interatrial septum

Two ventricles



Lower chambers
Left and right
Separated by
interventricular
septum
Atrioventricular septum separates the atria
from the ventricles
Click for
View of
Heart
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-12
The Heart: Structures (cont.)




Tricuspid valve – prevents blood from flowing back
into the right atrium when the right ventricle
contracts
Bicuspid valve – prevents blood from flowing back
into the left atrium when the left ventricle contracts
Pulmonary valve – prevents blood from flowing
back into the right ventricle
Aortic valve – prevents blood from flowing back Click for
View of
into the left ventricle
Heart
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-14
The Heart: Blood Flow
Deoxygenated
blood in from
body
Oxygenated
blood out to
body
Oxygenated
blood in lungs
Deoxygenated
blood out
to lungs
Atria Contract
Ventricles Contract
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-15
The Heart: Blood Flow (cont.)
Right
Atrium
Tricuspid
Valve
Right
Ventricle
Pulmonary
Valve
Body
Lungs
Aortic
Semilunar
Valve
Left
Ventricle
Bicuspid
Valve
Left
Atrium
Pulmonary
Semilunar
Valve
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-16
The Heart: Cardiac Cycle

One heartbeat = one cardiac cycle
Atria contract and relax
Ventricles contract and relax



Right atrium contracts



Tricuspid valve opens
Blood fills right ventricle
Right ventricle contracts




Tricuspid valve closes
Pulmonary semilunar valve
opens
Blood flows into pulmonary
artery
Left atrium contracts



Bicuspid valve opens
Blood fills left ventricle
Left ventricle contracts



Bicuspid valve closes
Aortic semilunar valve
opens
Blood pushed into aorta
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-17
The Heart: Cardiac Cycle (cont.)

Influenced by







Exercise
Parasympathetic nerves
Sympathetic nerves
Cardiac control center
Body temperature
Potassium ions
Calcium ions
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-18
The Heart: Heart Sounds

One cardiac cycle – two heart sounds (lubb
and dubb) when valves in the heart snap shut

Lubb – First sound


When the ventricles contract, the tricuspid and
bicuspid valves snap shut
Dubb – Second sound

When the atria contract and the pulmonary and aortic
valves snap shut
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-19
The Heart: Cardiac Conduction System

Group of structures that send electrical impulses through the heart

Sinoatrial node (SA node)





Wall of right atrium
Generates impulse
Natural pacemaker
Sends impulse to AV node
Atrioventricular node (AV
node)




Between atria just above ventricles
Atria contract
Sends impulse to the bundle of His
Bundle of His




Between ventricles
Two branches
Sends impulse to Purkinje
fibers
Purkinje fibers


Lateral walls of ventricles
Ventricles contract
Link to
Diagram
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-21
Apply Your Knowledge
Match the following:
ANSWER:
C Tricuspid valve
__
A. Two branches; sends impulse to Purkinje fibers
__
F Bicuspid valve
B. Covering of the heart and aorta
__
B Pericardium
C. Between the right atrium and the right ventricle
__
E SA node
D. In the lateral walls of ventricles
__
A Bundle of His
E. Natural pacemaker
D Purkinje fibers
__
F. Between the left atrium and the left ventricle
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-22
Blood Vessels: Arteries and Arterioles



Strongest of the
blood vessels
Carry blood away
from the heart
Under high pressure

Vasoconstriction
Vasodilation



Arterioles


Small branches of
arteries
Aorta

Takes blood from the
heart to the body
Coronary arteries

Supply blood to heart
muscle
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-23
Blood Vessels: Veins and Venules


Blood under no pressure in
veins

Does not move very easily

Skeletal muscle contractions
help move blood

Sympathetic nervous system
also influences pressure
Valves prevent backflow

Venules


Small vessels formed when
capillaries merge
Superior and inferior vena
cava

Largest veins

Carry blood into right atrium
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-24
Blood Vessels: Capillaries

Branches of arterioles

Smallest type of blood vessel

Connect arterioles to venules

Only about one cell layer thick

Oxygen and nutrients can pass out of a capillary into
a body cell

Carbon dioxide and other waste products pass out of
a body cell into a capillary
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-25
Apply Your Knowledge
How do arteries control blood pressure?
ANSWER: The muscular walls of arteries can constrict to
increase blood pressure or dilate to decrease blood
pressure.
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-26
Blood Pressure

Force blood exerts on the inner walls of blood vessels



Systolic pressure



Ventricles contract
Blood pressure is at its greatest in the arteries
Diastolic pressure



Highest in arteries
Lowest in veins
Ventricles relax
Blood pressure in arteries is at its lowest
Reported as the systolic number over the diastolic number
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-27
Blood Pressure (cont.)



Control is based mainly on the amount of blood pumped out
of the heart
The amount of blood entering should equal the amount
pumped from the heart
Starling's law of the heart


Blood entering the left ventricle stretches the wall of the ventricle
The more the wall is stretched


The harder it will contract and
tTe more blood it will pump out
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-28
Blood Pressure (cont.)

Baroreceptors

Also help regulate blood pressure

Located in the aorta and carotid arteries

High blood pressure in aorta  message to
cardiac center in brain  decreases heart rate
 lowers blood pressure

Low blood pressure in aorta  message to
cardiac center in the brain  increases heart rate
 increases blood pressure
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-29
Apply Your Knowledge
What is the difference between the systolic pressure
and diastolic pressure?
ANSWER: Systolic pressure is the result of the
contraction of the ventricles increasing the pressure in
the arteries. Diastolic pressure is the result of the
relaxation of the ventricles lowering the pressure in the
arteries.
Good Answer!
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-30
Circulation

Pulmonary circuit
right atrium  right ventricle  pulmonary artery
trunk  pulmonary arteries  lungs 
pulmonary veins  heart (left atrium)

Systemic circuit
left atrium  left ventricle  aorta  arteries 
arterioles  capillaries  venules  veins 
vena cava  heart (right atrium)
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-31
Circulation (cont.)

Arterial system

Carry oxygen-rich blood
away from the heart

Pulmonary arteries carry
oxygen-poor blood

Paired – left and right
artery of the same name
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-32
Circulation (cont.)

Venous system

Carries oxygenpoor blood toward
the heart



Hepatic portal system

Collection of veins
carrying blood to the
liver
Except pulmonary
veins
Most large veins
have the same
names as the
arteries they are
next to
Click for Larger View
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-34
Apply Your Knowledge
Do pulmonary arteries carry blood with high levels of
oxygen or low levels of oxygen?
ARTERIES: Pulmonary arteries carry oxygen-poor blood.
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-35
Blood

A type of connective
tissue




Red blood cells
(erythrocytes)
White blood cells
(leukocytes)
Platelets – cell
fragments
Plasma – fluid part of
blood
Average-sized adult has
4 to 6 liters of blood
Amount depends on:
 Size of person
 Amount of adipose tissue
 Concentrations of ions
 Females have less than
males
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-36
Blood Components

Hematocrit


The percentage of red blood
cells
Normal is about 45%

White cells and
platelets = 1%

Plasma = 55%
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-37
Blood Components: Red Blood Cells




Erythrocytes
Transport oxygen throughout the body
Small biconcave-shaped cells
Hemoglobin is a pigment in RBCs


Oxyhemoglobin carries oxygen; bright red
Deoxyhemoglobin does not carry oxygen; darker red



Carries carbon dioxide, so also called carboxyhemoglobin
Anemia – low RBC count
Erythropoietin – regulates production of RBCs
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-38
Blood Components: Red Blood Cells (cont.)
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27-39
Blood Components: White Blood Cells

Granulocytes




Neutrophils (55%) –destroy bacteria, viruses, and toxins in
the bloodstream (phagocytes)
Eosinophils (3%) – get rid of parasitic infections such as
worm infections
Basophils (1%) – control inflammation and allergic
reactions
Agranulocytes


Monocytes (8%) – destroy bacteria, viruses, and toxins in
blood
Lymphocytes (33%) – provide immunity for the body
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-40
Blood Components: White Blood Cells (cont.)

WBC count normally 5000 to 10,000 cells per
cubic millimeter of blood

Leukocytosis



Elevated WBC count
Usually due to infection
Leukopenia


Low WBC count
Some viral infections and other conditions
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-41
Blood Components: Platelets




Fragments of cells found in the bloodstream
Also called thrombocytes
Important in the clotting process of blood
Normal count

130,000 to 360,000 platelets per cubic
millimeter of blood
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-42
Blood Components: Plasma


Liquid portion of blood
composed mostly of water
Proteins



Smallest plasma proteins
Pull water in to help
maintain blood pressure
Globulins – transport lipids
and fat-soluble vitamins
Fibrinogen – needed for
blood clotting
Nutrients



Albumins







Amino acids
Glucose
Nucleotides
Lipids from the digestive
tract
Gases – oxygen, carbon
dioxide, and nitrogen
Electrolytes
Waste products
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-43
Blood: Bleeding Control

Hemostasis – the control
of bleeding

Three processes of
hemostasis



Blood vessel spasm
Platelet plug formation
Blood coagulation
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-44
Platelet plug
formation:
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-45
Blood Types

Types are distinguished
by antigen and
antibodies

Agglutination


Clumping of red blood
cells
Antigens on surface of
RBCs bind to
antibodies in plasma
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-46
Blood Types (cont.)
Blood Type
Antigen
Present
Antibody
Present
Blood That Can
Be Received
A
A
B
A and O
B
B
A
B and O
AB
AB
None
A, B, AB, and O
O
None
A and B
O
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-47
Blood Types (cont.)


Rh antigen – protein on
RBCs
RBCs contain the
Rh antigen
Rh-negative

RBCs do not contain
the Rh antigen
Rh-positive blood is
given to Rh-negative
person
 Antibodies form
Rh-positive




If Rh-negative person
receives more Rhpositive blood


Antibodies bind to the
donor cells
Agglutination occurs
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-48
Apply Your Knowledge
True or False:
ANSWER:
__
F Hematocrit is the percentage of WBCs in the blood.
RBCs
__
T Neutrophils destroy bacteria, viruses, and toxins in the bloodstream.
__
T Platelets are important to the clotting process. pulls water into
__
F Albumin is a small plasma protein that pushes water out of the bloodstream.
__
T Hemostasis is the control of bleeding.
can receive any type of blood
__
F A person with type AB blood can only receive type AB blood.
__
T Blood should be matched for Rh factor.
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-49
Chest Pain

Cardiac




Myocardial infarction
Angina
Pericarditis
Coronary spasm

Non-cardiac






Take all complaints of
chest pain seriously!

Heartburn
Panic attacks
Pleurisy
Costochondritis
Pulmonary embolism
Sore muscles
Broken ribs
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-50
Chest Pain (cont.)

Determine cause








Electrocardiogram
Stress tests
Blood tests
Chest x-ray
Nuclear scan
Coronary
catheterization
Echocardiogram
Endoscopy
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-51
Diseases and Disorders of the
Cardiovascular System
Disease
Anemia
Description
Aneurysm
The blood does not have enough red blood cells
or hemoglobin to carry an adequate amount of
oxygen to the body’s cells
A ballooned, weakened arterial wall
Arrhythmias
Abnormal heart rhythms
Carditis
Inflammation of the heart
Endocarditis
Inflammation of the innermost lining of the
heart, including valves
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-52
Diseases and Disorders of the
Cardiovascular System (cont.)
Disease
Description
Myocarditis
Inflammation of the muscular layer of the heart
Pericarditis
Inflammation of the membranes that surround
the heart (pericardium)
Congestive
Heart Failure
Weakening of the heart over time; heart is
unable to pump enough blood to meet body’s
needs
Coronary Artery Atherosclerosis; narrowing of coronary arteries
Disease (CAD) caused by hardening of the fatty plaque deposits
within the arteries
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-53
Diseases and Disorders of the
Cardiovascular System (cont.)
Disease
Description
Hypertension
High blood pressure; consistent resting blood
pressure equal to or greater than 140/90 mm Hg
Leukemia
Bone marrow produces a large number of
abnormal WBCs
Murmurs
Abnormal heart sounds
Myocardial
Infarction
Heart attack; damage to cardiac muscle due to a
lack of blood supply
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-54
Diseases and Disorders of the
Cardiovascular System (cont.)
Disease
Description
Sickle Cell
Anemia
Abnormal hemoglobin causes RBCs to change
to a sickle shape; abnormal cells stick in
capillaries
Thalassemia
Inherited form of anemia; defective hemoglobin
chain causes, small, pale, and short-lived RBCs
Thrombophlebitis Blood clots and inflammation develops in a vein
Varicose Veins
Twisted, dilated veins
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-55
Apply Your Knowledge
The doctor has told your patient she has anemia. How
would you explain this to the her?
ANSWER: Anemia is a condition in which a person does not
have enough red blood cells or hemoglobin in the blood to
carry an adequate amount of oxygen to body cells.
Bravo!
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-56
In Summary

Cardiovascular system



Blood



Transport system for body
Heart, arteries, veins, and capillaries
Transport medium
RBCs, WBCs, platelets, plasma
Medical assistant

Assists patients in understanding prevention and
treatments for cardiovascular problems
© 2009 The McGraw-Hill Companies, Inc. All rights reserved
27-57
End of Chapter
Your work is to
discover your world
and then with all your
heart give yourself to
it.
~ Buddha
© 2009 The McGraw-Hill Companies, Inc. All rights reserved