1. Cardiovascular System
Health Occupations

2. Also known as the cardiovascular system
Consists of heart, blood vessels, and blood
Transports oxygen and nutrients to body cells
Transports carbon dioxide and metabolic materials away from the body cells

3. Heart Muscular, hollow organ functions as pump
Size of a closed fist that pumps 100,000 times each day to pump an equivalent of 2000 gallons of blood through the body.
Location-in the mediastinal cavity, between the lungs, behind the sternum, and above the diaphragm

4. Three layers of tissue
Endocardium- smooth muscle that lines the inside of the heart.
Myocardium- the thickest layer and the muscular middle layer
Pericardium is the double layer membrane or sac, that covers the outside of the heart.
Pericardial fluid fills the space between the two layers to prevent friction and damage to the membranes as the heart contracts or beats.

5. Septum (muscular wall the separates the heart into a right and left side). It also prevents blood from moving between right and left sides of the heart.

6. Heart is divided into four parts or chambers:
Heart chambers
Right atrium receives blood as it returns from body cells.
Right ventricle-receives blood from right atrium and pumps the blood into the pulmonary artery
Left atrium- receives oxygenated blood from the lungs
Left ventricle- receives blood from the left atrium and pumps the blood into the aorta for transport to the body cells.

7. Valves- keeps the blood flowing in the right direction.
Tricuspid- located between the right atrium and right ventricle. It closes when the right ventricle contracts.
Pulmonary- located between the right ventricle and the pulmonary artery
Mitral- located between left atrium and left ventricle. It closes as left ventricle contracts
Aortic- located between the left ventricle and aorta (the largest artery in the body).

8. Follow a drop of blood through the heart:
Oxygenated blood returns through the right and left pulmonary veins into the left atrium.
From the left atrium, oxygenated blood flows through the bicuspid (mitral) valve into the left ventricle.
From the left ventricle, oxygenated blood flows through the aortic semilunar valve into the aorta.
From the aorta, oxygenated blood flows into arteries, arterioles, capillaries, venules, and veins, eventually reaching the superior and inferior vena cava once again.
The superior vena cava drains deoxygenated blood from the head, neck, and arms while the inferior vena cava drains deoxygenated blood from the abdomen and the legs into the right atrium. The coronary sinus drains deoxygenated blood from the myocardium into the right atrium.
From the right atrium, deoxygenated blood flows through the tricuspid valve into the right ventricle.
From the right ventricle, deoxygenated blood flows through the pulmonary semilunar valve into the pulmonary trunk.
The pulmonary trunk branches to form the right and left pulmonary arteries, which take deoxygenated blood to the lungs for gas exchange. Carbon dioxide is released from the
blood while oxygen is picked up by the blood.

9. Heart Diagram

10. Flow of blood through the heart

11. Cardiac Cycle (heartbeat)
Consists of a brief period of rest (diastole) followed by a period of ventricular contraction (systole)
What happens is at the start of the cycle, the atria contract, and push the blood into the ventricles.
Then the atria relaxes, and then the blood that is returning from the body, enters the right atrium while the blood returning from the lungs enters the left atrium.
As the atria are filling systole beings and the ventricles contract.

12. Conductive pathways
A group of nerve cells located in the right atrium are called the sinoatrial (SA node) or the pacemaker.
This sends out an electrical impulse that spreads out over the muscles in the atria. The atria then contract and push blood into the ventricles.
Once it passes through the atria, it reaches the atrioventricular node (AV node)
AV node sends the electrical impulse through the Bundle of His which divides further into the Left Bundle branch and Right Bundle Branch. These then carry the impulses down to the Purkinje Fibers.

13. Arrhythmias
Interference with normal conduction pattern causes arrhythmias.
Arrhythmia are abnormal heart rhythms and can be mild to life threatening.

14. Pacemakers Regulate the hearts rhythm.
It is a small battery powered device with electrodes.
The electrodes are threaded through a vein and positioned in the right atrium and in the apex of the right ventricle.
It will monitor the hearts activity and delivers an impulse through the elctrodes

15. Blood Vessels Blood carried throughout body in blood vessels
Arteries carry blood away from the heart. The aorta is the largest artery in the body; it receives blood from the left ventricle of the heart.
Capillaries- connect arterioles with venules (the smallest veins). Have thin walls which allow oxygen and nutrients to pass though to the cells and allow CO2and metabolic products from the cells to enter the capillaries
Veins- carry blood back to the heart. The two largest veins are the superior vena cava and the inferior vena cava.
Superior vena cava brings blood from the upper part of the body and the inferior vena cava brings it from the lower part of the body.

16. Blood Average adult: 4-6 quarts
Blood circulates continuously throughout the body, often called a tissue because it contains many cells
Transports many substances like oxygen, carbon dioxide, nutrients, hormones

17. Plasma Blood is made of this. Plasma is approximately 90% water
Also contains, fibrinogen, and prothrombin, vitamins,

18. Blood Cells
Erythrocytes or red blood cells are produced in red bone marrow at a rate of 1 million a minute. Live approximately 120 days before being broken down. Contain hemoglobin.
Hgb is a protein made up of globin and an iron compound called heme. It carries both oxygen and carbon dioxide. When it carries oxygen, blood has the red color. When it has less oxygen and more carbon dioxide, the blood gets darker and sometimes will have a bluish cast to it.

19. Leukocytes or white blood cells
Not as numerous as the RBCs
Formed in the bone marrow and lymph tissue
Live about 3-9 days
Can pass through capillary walls into the body tissue
Main function is to fight infection
phagocytosis
5 types of WBC and function include:
Neutrophil-phagocytize bacteria by secreting an enzyme called lysozyme
Eosinphils-removes toxins and defends the body against allergic reactions by producing antihistamines
Basophils- participate in the inflammatory response. This helps produce histamine (a vasodilator), and heparin (anticoagulant).
Monocytes-phagocytize bacteria and foreign materials.
Lymphocytes-provide immunity for the developing antibodies. Protects against the formation of cancer cells

20. Thrombocytes Also called platelets
Lack a nuclei, vary in shape and size, and usually are referred as fragments or pieces of cells.
Formed in bone marrow.
Live for about 5-9 days.
Important for the clotting process.

21. Diseases and Abnormal Conditions
Anemia- inadequate number of RBC, hemoglobin or both
Symptoms- pallor (paleness), fatigue, dyspnea (difficult breathing), and a rapid heart rate.
etiology- blood lost, chemotherapy, formation of abnormal erythrocytes such as pernicious anemia, or sickle cell anemia
Treatment can include:
Blood transfusions
Bone marrow transplant
Administering Vitamin B12

22. Aneurysm A ballooning out of, or sac like formation on an artery wall.
Etiology- anything that causes a weakening arterial wall:
Injuries, congenital defects, and disease
Symptoms-usually no pain but some can and even can cause pressure
Common sites-cerebral aortal and abdominal arteries
If rupture can hemorrhage, and death may occur
Surgery is the mode of treatment replacing the damaged area with a plastic graft or another blood vessel.

23. Arteriosclerosis/Atherosclerosis
Is hardening of the arteries or thickening of the arterial walls which results in a loss of elasticity and contractility.
Results from aging
Causes high blood pressure (hypertension)
Can lead to aneurysm or a CVA (stroke)
Main focus is lowering blood pressure through diet, medications and exercize
Occurs when fatty plaques (cholesterol) are deposited on the walls of the arteries.
Causes a narrowing, which reduces blood flow
Plaque can break loose (emboli)
Low cholesterol diet, and medication used to treat, exercising, no smoking.
Angioplasty, bypass surgery, or stent placement may need to be done.

24. Congestive heart failure (CHF)
Heart does not beat adequately to supply the blood needs of the body.
Can involve rights side of the heart of the left.
Treatment includes drugs to strengthen the heart, diuretics (rid of fluid), O2, bed rest, low sodium diet
Symptoms include:
Edema, dyspnea, pallor, cyanosis, distended neck veins, a weak, rapid pulse, frothy pink tinged cough

25. Embolus A foreign substance circulating in the blood stream.
It can be air, blood clot, bacterial clumps, a fat globule, or other substances similar.
If it enter an artery or a capillary too small for passage, blockage occurs

26. Hemophilia Inherited disease
Occurs in males mostly but females can have it as well.
There is a lack of plasma protein required for clotting.
Treatment includes blood transfusions, plasma, platelets or the missing protein factor

27. Hypertension High blood pressure
A systolic pressure above 140 and a diastolic pressure above 90 mm/Hg is usually considered HTN.
Risk factors include-family, race, obesity, stress, smoking, aging, and diet
No cure. Can be controlled through medications, diet, and exercise, avoid smoking, stress.
If not controlled may lead to heart, blood vessel, and kidney damage.

28. Leukemia Malignant disease of the bone marrow or lymph tissue.
Etiology- high number of immature WBCs
Symptoms include- fever, pallor, swelling of lymphoid tissue, fatigue, anemia, bleeding gums, excessive bruising, and joint pain.
Treatment- chemo, radiation and or bone marrow transplant.

29. Myocardial Infarction
Heart attack
Blockage of coraonary arteries cuts off supply to the heart. Heart tissue dies (infarct).
Symptoms – severe crushing pain (angina pectoris) radiates to arm, neck, and jaw. Pressure in chest, perspiration, cold, clammy skin, dyspnea and a change in blood pressure.
CPR if heart stops, clot busting drugs such as TPA (tissue plasminogen activator) or streptokinase (needs to be used within the first several hours
Bed rest, O2, medications to strengthen the heart, anticoags, control of BP and diet

30. Phlebitis Inflammation of the vein (leg)
If clot (thrombus) occurs it is called thrombophlebitis
Pain, edema, redness, and discoloration at the site.
Anticoagulants, pain medication, elevation of affected limb, Antiembolism stockings, and possibly surgery.

31. Varicose Veins
Dilated, swollen veins that have lost elasticity and cause stasis, or decreased blood flow.
Occur in the legs
Result from pregnancy, long periods of standing or sitting, and hereditary factors.
Exercise, avoidance of prolonged sitting or standing and tight fitting or restrictive clothing
Surgery may be necessary.