cardiovascular system

1. © 2009 The McGraw-Hill Companies, Inc. All rights reserved
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The Cardiovascular System
PowerPoint® presentation to accompany:
Medical Assisting
Third Edition
Booth, Whicker, Wyman, Pugh, Thompson

2. © 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.

3. © 2009 The McGraw-Hill Companies, Inc. All rights reserved
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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.

4. © 2009 The McGraw-Hill Companies, Inc. All rights reserved
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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.

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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.

6. © 2009 The McGraw-Hill Companies, Inc. All rights reserved
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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

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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

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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

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The Heart: Structures (cont.)
 Heart coverings
 Pericardium
 Covers the heart and
large blood vessels
attached to the heart
 Visceral pericardium
 Innermost layer
 Directly on the heart
 Parietal pericardium
 Layer on top of the
visceral pericardium
 Heart walls:
 Epicardium
 Outermost layer
 Fat to cushion heart
 Myocardium
 Middle layer
 Primarily cardiac muscle
 Endocardium
 Innermost layer
 Thin and smooth
 Stretches as the heart
pumps
Click for Larger View

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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
Click for
View of
Heart
 Atrioventricular septum separates the atria
from the ventricles

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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
into the left ventricle
Click for
View of
Heart

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The Heart: Blood Flow
Deoxygenated
blood in from
body
Oxygenated
blood in lungs
Atria Contract Ventricles Contract
Deoxygenated
blood out
to lungs
Oxygenated
blood out to
body

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The Heart: Blood Flow (cont.)
Right
Atrium
Right
Ventricle
Pulmonary
Semilunar
Valve
Left
Atrium
Bicuspid
Valve
Left
Ventricle
Pulmonary
Valve
Tricuspid
Valve
Aortic
Semilunar
Valve
Lungs
Body

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The Heart: Cardiac Cycle
 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
 One heartbeat = one cardiac cycle
 Atria contract and relax
 Ventricles contract and relax

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The Heart: Cardiac Cycle (cont.)
 Influenced by
 Exercise
 Parasympathetic nerves
 Sympathetic nerves
 Cardiac control center
 Body temperature
 Potassium ions
 Calcium ions

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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

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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

18. © 2009 The McGraw-Hill Companies, Inc. All rights reserved
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Apply Your Knowledge
Match the following:
__ Tricuspid valve A. Two branches; sends impulse to Purkinje fibers
__ Bicuspid valve B. Covering of the heart and aorta
__ Pericardium C. Between the right atrium and the right ventricle
__ SA node D. In the lateral walls of ventricles
__ Bundle of His E. Natural pacemaker
__ Purkinje fibers F. Between the left atrium and the left ventricle
D
A
E
B
F
C
ANSWER:

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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

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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

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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

22. © 2009 The McGraw-Hill Companies, Inc. All rights reserved
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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.

23. © 2009 The McGraw-Hill Companies, Inc. All rights reserved
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Blood Pressure
 Force blood exerts on the inner walls of blood vessels
 Highest in arteries
 Lowest in veins
 Systolic pressure
 Ventricles contract
 Blood pressure is at its greatest in the arteries
 Diastolic pressure
 Ventricles relax
 Blood pressure in arteries is at its lowest
 Reported as the systolic number over the diastolic number

24. © 2009 The McGraw-Hill Companies, Inc. All rights reserved
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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

25. © 2009 The McGraw-Hill Companies, Inc. All rights reserved
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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

26. © 2009 The McGraw-Hill Companies, Inc. All rights reserved
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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!

27. © 2009 The McGraw-Hill Companies, Inc. All rights reserved
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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)

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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

29. © 2009 The McGraw-Hill Companies, Inc. All rights reserved
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Circulation (cont.)
 Venous system
 Carries oxygen-
poor blood toward
the heart
 Except pulmonary
veins
 Most large veins
have the same
names as the
arteries they are
next to
 Hepatic portal system
 Collection of veins
carrying blood to the
liver
Click for Larger View

30. © 2009 The McGraw-Hill Companies, Inc. All rights reserved
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Apply Your Knowledge
ARTERIES: Pulmonary arteries carry oxygen-poor blood.
Do pulmonary arteries carry blood with high levels of
oxygen or low levels of oxygen?

31. © 2009 The McGraw-Hill Companies, Inc. All rights reserved
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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

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Blood Components
 Hematocrit
 The percentage of red blood
cells
 Normal is about 45%
 White cells and
platelets = 1%
 Plasma = 55%

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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

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Blood Components: Red Blood Cells (cont.)

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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

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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

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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

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Blood Components: Plasma
 Liquid portion of blood
composed mostly of water
 Proteins
 Albumins
 Smallest plasma proteins
 Pull water in to help
maintain blood pressure
 Globulins – transport lipids
and fat-soluble vitamins
 Fibrinogen – needed for
blood clotting
 Nutrients
 Amino acids
 Glucose
 Nucleotides
 Lipids from the digestive
tract
 Gases – oxygen, carbon
dioxide, and nitrogen
 Electrolytes
 Waste products

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Blood: Bleeding Control
 Hemostasis – the control
of bleeding
 Three processes of
hemostasis
 Blood vessel spasm
 Platelet plug formation
 Blood coagulation

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Platelet plug
formation:

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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

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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

43. © 2009 The McGraw-Hill Companies, Inc. All rights reserved
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Blood Types (cont.)
 Rh antigen – protein on
RBCs
 Rh-positive
 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
 If Rh-negative person
receives more Rh-
positive blood
 Antibodies bind to the
donor cells
 Agglutination occurs

44. © 2009 The McGraw-Hill Companies, Inc. All rights reserved
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Apply Your Knowledge
True or False:
__ Hematocrit is the percentage of WBCs in the blood.
__ Neutrophils destroy bacteria, viruses, and toxins in the bloodstream.
__ Platelets are important to the clotting process.
__ Albumin is a small plasma protein that pushes water out of the bloodstream.
__ Hemostasis is the control of bleeding.
__ A person with type AB blood can only receive type AB blood.
__ Blood should be matched for Rh factor.
pulls water into
RBCs
can receive any type of blood
T
T
F
T
F
T
F
ANSWER:

45. © 2009 The McGraw-Hill Companies, Inc. All rights reserved
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Chest Pain
 Cardiac
 Myocardial infarction
 Angina
 Pericarditis
 Coronary spasm
 Non-cardiac
 Heartburn
 Panic attacks
 Pleurisy
 Costochondritis
 Pulmonary embolism
 Sore muscles
 Broken ribs
Take all complaints of
chest pain seriously!

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Chest Pain (cont.)
 Determine cause
 Electrocardiogram
 Stress tests
 Blood tests
 Chest x-ray
 Nuclear scan
 Coronary
catheterization
 Echocardiogram
 Endoscopy

47. © 2009 The McGraw-Hill Companies, Inc. All rights reserved
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Diseases and Disorders of the
Cardiovascular System
Disease Description
Anemia The blood does not have enough red blood cells
or hemoglobin to carry an adequate amount of
oxygen to the body’s cells
Aneurysm 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

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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
Disease (CAD)
Atherosclerosis; narrowing of coronary arteries
caused by hardening of the fatty plaque deposits
within the arteries
Diseases and Disorders of the
Cardiovascular System (cont.)

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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
Diseases and Disorders of the
Cardiovascular System (cont.)

50. © 2009 The McGraw-Hill Companies, Inc. All rights reserved
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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
Diseases and Disorders of the
Cardiovascular System (cont.)

51. © 2009 The McGraw-Hill Companies, Inc. All rights reserved
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Apply Your Knowledge
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.
The doctor has told your patient she has anemia. How
would you explain this to the her?
Bravo!

52. © 2009 The McGraw-Hill Companies, Inc. All rights reserved
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In Summary
 Cardiovascular system
 Transport system for body
 Heart, arteries, veins, and capillaries
 Blood
 Transport medium
 RBCs, WBCs, platelets, plasma
 Medical assistant
 Assists patients in understanding prevention and
treatments for cardiovascular problems

53. © 2009 The McGraw-Hill Companies, Inc. All rights reserved
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End of Chapter
Your work is to
discover your
world and then
with all your
heart give
yourself to it.
~ Buddha