1. The Cardiovascular System
Chapter 27
The Cardiovascular System
PowerPoint® presentation to accompany:
Medical Assisting
Third Edition
Booth, Whicker, Wyman, Pugh, Thompson

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. 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. 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.

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.

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

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

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

9. 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
Click for Larger View
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

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

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 into the left ventricle
Click for View of Heart

13. The Heart Labeled

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

15. 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

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

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

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

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

21. Good Job! Apply Your Knowledge ANSWER: 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 C
ANSWER: F B E A D
Good Job!

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

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

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

25. Apply Your Knowledge Correct! How do arteries control blood pressure?
ANSWER: The muscular walls of arteries can constrict to increase blood pressure or dilate to decrease blood pressure.
Correct!

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. 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

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

29. Apply Your Knowledge Good Answer!
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!

30. Circulation Pulmonary circuit Systemic 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)

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

32. Circulation (cont.) Venous system Hepatic portal 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

34. Apply Your Knowledge YIPPEE!
Do pulmonary arteries carry blood with high levels of oxygen or low levels of oxygen?
ARTERIES: Pulmonary arteries carry oxygen-poor blood.
YIPPEE!

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

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

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

38. Blood Components: Red Blood Cells (cont.)

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

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

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  

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

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

44. Platelet plug formation:

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

46. Blood That Can Be Received
Blood Types (cont.)
Blood Type
Antigen Present
Antibody Present
Blood That Can Be Received A B
A and O
B and O AB
None
A, B, AB, and O O
A and B

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

48. can receive any type of blood
Apply Your Knowledge F
ANSWER:
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.
RBCs T T
pulls water into F T
can receive any type of blood F T
Truely Terrific!

49. Take all complaints of chest pain seriously!
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!

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

51. Diseases and Disorders of the Cardiovascular System
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

52. Diseases and Disorders of the Cardiovascular System (cont.)
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

53. Diseases and Disorders of the Cardiovascular System (cont.)
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

54. Diseases and Disorders of the Cardiovascular System (cont.)
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

55. Bravo! 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!

56. In Summary Cardiovascular system Blood Medical assistant
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

57. End of Chapter
End of Chapter 27
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