1. 12.3 Circulatory Disorders
Pg. 494

2. Arteriosclerosis
Thickening of the arteries, loss of elastic properties = hardening
Most common type is atherosclerosis
Plaque (fatty deposits, calcium, and fibrous tissue) build up on the side of artery walls
Blood flow decreases and blood pressure increases
May lead to angina (chest pain), blood clots, shortness of breath, heart attack, or heart failure
Reduce risks by exercising, not smoking, eating a diet low in saturated fats and high in fruits and vegetables
-plaque is dangerous if it occurs in arteries that supply the heart, brain, legs, and kidneys
-90% of heart attacks are caused by atherosclerosis

3. Surgeon inserts a tube into a clogged artery
Treatable with….
Angioplasty
Surgeon inserts a tube into a clogged artery
Tiny balloon inflates to force open the artery
Small, permanent wire-mesh tube (known as a vascular stent) inserted during procedure to open the vessel and reduce the chance of blockage
Coronary Bypass
Re-routing blood flow rather than unblocking blood vessels
Taking part of a healthy artery or vein from a healthy region (ex. leg) and using it to create a new pathway
-stent’s are only used sometimes

4. Heart Attack Coronary arteries supply O2 to the heart, when these
narrow blood cannot flow as efficiently
If plaque ruptures a blood clot may occur -> blocked artery -> heart becomes “starved” for O2 -> death of heart muscle cells -> can cause permanent damage
Coronary arteries may also spasm, reducing blood supply to the heart (Ischemia)
Healing of the heart takes about 8 weeks and scars will form around the damaged area (BUT it does NOT contract)
Drug therapy used to break up the clot (antiplatelets and/or clot busters), aspirin to prevent from worsening, bypass surgery or angioplasty if needed
-amount of damage to the heart muscle depends on the size of the area supplied by the blocked artery and time between injury and treatment
-having a heart attack does not mean you will never have one again

5. Aneurysm
A bulge in an artery due to a weakened area of the arterial wall
Blood pressure enlarges the aneurysm over time, increasing the chances of it bursting
If it bursts, internal bleeding occurs which may lead to death
Most occur in the Aorta
Treatable with surgery
Remove the dead portions of blood vessels and replace it with a patch or graft of synthetic material

6. Heart Valve Diseases
Regurgitation = valve does not close completely, allowing back flow of blood
Stenosis = thickening or scarring of the valve (narrowing) inhibits blood flow out of the ventricle or atria
Note: stenosis and regurgitation can happen at the same time, and can affect more than 1 valve -> reduces the hearts ability to pump blood through the body -> may lead to heart failure
Causes of diseases:
Ageing, damage from infection, previous heart attack, and connective tissue disorders
Regurgitation = blood does NOT move forward through the valve

7. Continued… Surgeons may replace or repair valves
May be taken from animal or human resources, or made from metal, plastic, or other synthetic materials
Mitral valve prolapse = 1 or both mitral valve (or bicuspid valve) flaps bulges back into the atrium -> prevents the valve from sealing tightly
Very common form of heart valve disease

8. Arrhythmia Problem with the speed or rhythm of the heartbeat
Irregular heartbeat may be harmless OR pumps insufficient blood flow to the brain or other organs
May be treated with medications OR may require surgery -> artificial pacemaker
Pacemaker = small device emitting an electrical impulse to control the rate of heartbeats when heartbeat is abnormal
Signals the atria, ventricles or both
Pacemakers are attached just under the skin of the chest and usually includes a sensor that monitors the heart

9. Congenital Heart Defects
A defect in the heart present from birth -> may cause cardiovascular problems
Includes: problems in the walls dividing the chambers, in valves, and in the structure of blood vessels near the heart
Heart murmur = abnormalities in blood flow through the heart, such as 1+ valves not opening or closing properly
Valve defects are heard with a stethoscope
Acquired heart defect rather than congenital
Stethoscopes allows us to hear the whooshing or rasping sound, which occurs when blood leaks out from the valve

10. Continued…
Surgeons can repair or reduce damage caused by congenital heart defects
Digitizing technology uses CT scan data OR MRI scan and create an exact model (plastic or wax) of a body part such as a heart
Surgeons use models to plan and practice the surgery beforehand
The internet allows surgeons from around the world to input data and create models for patients
CT = computed tomography

11. Stroke
Arteries supplying blood to the brain are damaged, cutting off oxygen and nutrients to brain tissue
Ischemic stroke = clot in a blood vessel blocks flow of blood to the brain
Hemorrhagic stroke = blood vessel bursts in the brain and blood flows into surrounding regions of the brain
Both types kill brain cells in the affected area
-death occurs when nerve control to vital organs is affected
The longer without O2 = greater risk or permanent brain damage (varies from partial paralysis to death)

12. Continued…
Treatment MUST start within a few hours of symptoms in order to be effective!
3 emergency treatments:
Clot busters (drugs)
Surgery
Non-surgical procedures
-method of treatment depends on the type of stroke, how serious the stroke is, the age and general health of the patient, and how soon treatment is started

13. Diagnosing Circulatory System Disorders

14. Done to determine cause of stroke and risk of blood clots
Coronary angiography = mapping coronary arteries via X-rays and the use of liquid dye -> determines blockage
Echocardiogram (ECHO) = an ultrasound creates a picture of the heart using sound waves
Done to determine cause of stroke and risk of blood clots
Exercise electrocardiogram (ECG) also known as a coronary stress test = measures the hearts electrical activity, blood pressure, and heart rate while exercising
-ECHO = sound waves determine the shape and movement of heart valves, the size of the heart chambers, how well the heart is functioning
-ECG = measures heart’s response to stress of exercise …performed to determine unexplained chest pain, or whether the person is experiencing irregular heartbeats, excessive dizziness, or fatigue

15. usually used in conjunction with other tests, such as an angiography
Holter monitor = wear over 24 to 48 hour period, and is attached to the chest via small electrodes
Event monitor = small device, similar to a wristwatch, that you activate when symptoms occur
Cardiac catheterization = thin, flexible tube called a catheter is inserted through an artery into the groin or the arm -> guided through the body to the heart -> X-ray taken with inserted dye
usually used in conjunction with other tests, such as an angiography
Note: heart monitors are used when disturbances in heart rhythms are detected
-holter monitor devices record the person while the person goes about their day and produces a diagnostic pattern to be later analyzed by a computer to determine the possible cause of the problem
-event monitor devices record the person’s reading and the wearer then phones the reading in to a special monitoring station o

16. Blood Disorders

17. Hemophilia Inherited, life-threatening condition
Rare, usually in males
Caused by insufficient clotting proteins in the blood
Person will bleed for a long time and is at risk of dying from a minor injury
Some can be treated with an
injection of the missing protein
factor VIII
-think internal bleeding

18. Anemia
Fairly common but often mild and short term, and easily treatable with supplements
Blood contains fewer than normal healthy RBC’s
Can be caused by blood loss or when RBC’s do NOT contain enough hemoglobin (carries O2)
Symptoms:
Dizziness, fatigue, shortness of breath, headache, cold hands and feet
Can be life-threatening if lack of O2 in blood damages the brain, heart and other organs -> may lead to death

19. Leukemia Cancer of WBC’s Two main types:
Myeloid = presence of too many leukocytes, which are immature and unable to fight infection
Also crowd out RBC’s causing anemia and fatigue
lymphoid = cancer of lymphocytes, but symptoms are VERY similar to myeloid leukemia

20. Continued… Both types of leukemia occur in 1 of 2 states…
Acute: symptoms appear suddenly, death follows quickly
Chronic: may go undetected for months or years
Treatment:
Blood transfusions to increase # of RBC’s and healthy WBC’s
Chemotherapy
Bone marrow transplant -> healthy marrow allows WBC’s to grow
-20 years ago children diagnosed with leukemia had less than 50% of survival but survival rat enow is 85%-bone marrow is the soft t issue in the large bones where blood cells are formed

21. Other treatment methods

22. Xenotransplants = transplanting cells, tissues, and
organs from between species
Transplanted organs are called grafts
Chemically treated, not living, functional tissue
Risk of transmitting diseases and risk of rejection
BIG difference between organ donation and human trafficking (Black Market)
Artificial hearts = artificial, self-contained mechanical pumps
Made of titanium and plastic, weighs less than 1Kg
Uses a hydraulic pump -> pumps more than 10L blood/minute
Powered by batteries (1 is external in a belt pack, 1 is internal)
Electronic controller in the abdomen monitors and controls the pump speed of the heart
-graft example includes pig heart valves in humans to replace damaged valves
-prior to synthetic material such as gore-tex and dacron, blood vessels from cows were often used to replace damaged human blood vessels
-many health, safety, legal, ethical, and regulatory issues to consider beforehand
-rejection will occur if the recipients immune system won’t function with the new tissues
-artificial hearts are now being used because of faulty human hearts and is a way of addressing the rising demand for donor organs
-the outside battery transmits wireless energy across the skin to the recharble battery inside the persons abdomen…this allows a person to take it off and shower whiel the other body is inside

23. Medical applications of nanotechonology -> use of microscopic structures (fractions of a width of human hair)
Detects changes in cells and molecules by detecting biomarkers
help in diagnosing cardiovascular and other disease quickly and
accurately -> earlier detection, more individualized patient care, reduced costs
Target drug delivery
Ex. chemotherapy = use of drugs that kill cancer cells -> also kill healthy cells and produce unpleasant side effects
Nanotechnology technique use cancer enzymes as biomarkers to target and deliver = localized drug therapy
Microscopic containers of drugs, made of biodegradable gels -> injected into body and drug is only released upon certain enzyme contact
Nanovalve = drug delivery system to released drugs having a basic pH
Biomarkers = molecules that point to the development of particular diseases
-can detect heart disease within 30mins from the time a blood sample is taken
-localized drug therapy will NOT touch the healthy cells in the surrounding area because cancer cells produce a different enzyme than the healthy cell surrounding it
-pH of a healthy tissue varies from that of diseased tissue, so the nanovalve opens to release the drug when the body’s internal environment is at a basic pH

24. Homework Review 12.3 Work on your project!!
STUDY FOR YOUR QUIZ ON TOMORROW!!