© 2009 The McGraw-Hill Companies, Inc. All rights reserved 27-1 The Cardiovascular System PowerPoint® presentation to accompany: Medical Assisting Third.

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

27-1

The Cardiovascular SystemThe Cardiovascular SystemPowerPoint® presentation to accompany:

Medical AssistingThird Edition

Booth, Whicker, Wyman, Pugh, Thompson

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.

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.

27-4



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.

27-5



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.

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

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

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

27-9



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

27-11



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

27-12



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

27-14


The Heart: Blood Flow

Deoxygenated blood in from

bodyOxygenated

blood in lungs

Atria Contract Ventricles Contract

Deoxygenated blood out to lungs

Oxygenated blood out to

body

27-15


The Heart: Blood Flow (cont.)

Right Atrium

Right Ventricle

PulmonarySemilunar

Valve

Left Atrium

BicuspidValve

Left Ventricle

PulmonaryValve

TricuspidValve

AorticSemilunar

Valve

LungsBody

27-16


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

27-17


The Heart: Cardiac Cycle (cont.)

Influenced by Exercise Parasympathetic nerves Sympathetic nerves Cardiac control center Body temperature Potassium ions Calcium ions

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

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

27-21


Apply Your KnowledgeMatch 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

CANSWER:

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

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

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

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.

27-26


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

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

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

27-29



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!

27-30


Circulation Pulmonary circuit

right atrium right ventricle pulmonary artery trunk pulmonary arteries lungs pulmonary veins heart (left atrium)

Systemic circuitleft atrium left ventricle aorta arteries

arterioles capillaries venules veins vena cava heart (right atrium)

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

27-32


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

27-34



ARTERIES: Pulmonary arteries carry oxygen-poor blood.

Do pulmonary arteries carry blood with high levels of oxygen or low levels of oxygen?

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

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

27-36


Blood Components

Hematocrit The percentage of red blood

cells Normal is about 45%

White cells and platelets = 1%

Plasma = 55%

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

27-38


Blood Components: Red Blood Cells (cont.)

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

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

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

27-42


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

27-43


Blood: Bleeding Control Hemostasis – the control

of bleeding

Three processes of hemostasis

Blood vessel spasm Platelet plug formation Blood coagulation

27-44


Platelet plug formation:

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

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

27-47


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

27-48


Apply Your KnowledgeTrue 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:

27-49


Chest Pain Cardiac

Myocardial infarction Angina Pericarditis Coronary spasm

Non-cardiac Heartburn Panic attacks Pleurisy Costochondritis Pulmonary embolism Sore muscles Broken ribsTake all complaints of

chest pain seriously!

27-50


Chest Pain (cont.)

Determine cause Electrocardiogram Stress tests Blood tests Chest x-ray Nuclear scan Coronary

catheterization Echocardiogram Endoscopy

27-51


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

27-52


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.)

27-53


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


27-54


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


27-55



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!

27-56


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

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 27-1 The Cardiovascular System PowerPoint® presentation to accompany: Medical Assisting Third.

Documents

blood slide

mcgrawhill companies

blood types

heart pumps

heart rate

flow of blood

components of blood

blood pressure