Circulatory Disease By Dr. Lamarine. “The future’s uncertain and the end is always near…”...
-
Upload
justin-hines -
Category
Documents
-
view
220 -
download
0
Transcript of Circulatory Disease By Dr. Lamarine. “The future’s uncertain and the end is always near…”...
Circulatory Disease
By Dr. Lamarine
“The future’s uncertain and the end is always near…”
-Jim Morrison
HUMAN BODY SYSTEMS
CIRCULATORY DIGESTIVE RESPIRATORY EXCRETORY NERVOUS ENDOCRINE REPRODUCTIVE
HEART ATTACK AND STROKE
75 million people with heart & blood vessel disease; @ 900,000 deaths annually
atherosclerosis major cause serious heart & blood vessel disease
inflammation major cause of plaque ruptures; related to diet (sugar/saturated fats) & bacteriaC reactive peptide (CRP) blood test for inflammation
endothelium, thin film tissue lining blood vessels, protects vs. heart disease & stroke (Teflon like lining for 50,000 miles of BVs)
unhealthy endothelium like Velcro
endothelium health via exercise & diet
BLOOD: @ 5/6 quarts: @ 50% cellular elements(RBCs, WBC, platelets) in plasma
bone marrow: manufactures RBCs; process called hematopoiesis
raw material for RBCs: protein, B12, folic acid*, iron * (neural tube defects)
anemia: “without blood” e.g. iron deficiency anemia; body has @ 4 gm iron (Fe); 75% in hemoglobin
infants need iron supplementation > 6 months
polycythemia: abnormal increase in RBCs
FUNCTIONS OF BLOOD
5-6 quarts of blood:
hematocrit = % by volume of RBCs
Functions of blood:
1. transportation: nutrients, wastes, gases
2. protection: bleeding, infections
3. homeostasis: pH, temp., electrolytes
ABNORMALITIES OF BLOOD COAGULATION
Platelets: 1. seal small breaks in capillaries 2. liberate vasoconstrictors 3. initiate blood coagulation
Thrombocytopenia: decrease in platelets
Hematomas: large areas of hemorrhage (black & blue)
Hemophilia: X-linked hereditary disease of males
SICKLE CELL DISEASE
An inherited blood disease where blood
lacks hemoglobin and RBC have a
sickle shape which can lead to
blood clots and organ damage.
{due to a single amino acid change}
SS (homozygous dominant): no disease
ss (homozygous recessive): disease
Ss (heterozygous): no disease but…
0.15% U.S. blacks have disease
1100 cases/yr; RBCs live 16 days vs.
Normal 120
10% U.S. blacks carriers
Two people who are carriers:
___S_______s___
S SS Ss
s Ss ss ________________
25% have disease: ss50% carriers: Ss25% no disease/not carriers: SS
ANATOMY OF THE HEART
Pumps 1.3 gallons/minute of blood and 5 gallons during peak exercise
Arteries have thick walls and carry blood away from the heartVeins have thin walls and carry blood to the heartMicroscopic capillaries-no cell not touching a capillary (except lens &
cornea)
Heart located in center of chest in thoracic cavity
The right (venous) heart receives deoxygenated blood from the body and delivers it to the lungs
The left heart receives oxygenated blood from the lungs and delivers it to the body
Both sides of the heart have upper (atria) and lower (ventricles) chambers
The coronary arteries supply blood to the heart itself (left & right coronary arteries)
PHYSIOLOGY OF THE HEART
Rests 0.25 seconds per beat
Systole is the active compression or squeezing of the ventricles that pushes blood out to the lungs or the body
Diastole is the relaxation of the ventricles when they are filling with blood
Stroke volume is the amount of blood pumped out of the left ventricle in one stroke
ATHEROSCLEROSIS
Begins with injury to inner lining of blood vessel, the endothelium.
A white blood cell (monocyte) sticks to an endothelial cell after an injury, then enters endothelial space (intima), where it is transformed into a lipid-ingesting macrophage.
The macrophage gorges on fat and turns into a lipid-filled foam cell, one of the main components of the “fatty streak”.
Size of fatty streak increases & may ultimately become mineralized with calcium to form an athrerosclerotic plaque.
Risk Factors for Atherosclerosis:
Elevated blood lipids/cholesterolHigh blood pressureSmokingDiabetesInflammation
Angina pectoris: pain caused by myocardial ischemia
Artherosclerosis can cause:
Cardiac arrest: cessation of normal cardiac contractions “heart attack”, triggered by:
1. sudden blockage of coronary artery2. hemorrhage into an atheromatous plaque (inflammation)3. arterial spasm (cocaine?)4. sudden greatly increased myocardial oxygen requirements
THROMBUS: intravascular clot-thrombosis
EMBOLUS: clot in circulation-embolism-blood clots in legs due to rest or varicose veins-postoperative thrombosis in legs-trauma-pulmonary embolism-estrogen in oral contraceptives-advanced cancer-fat embolism after bone fracture-air embolism after chest wound
MYOCARDITIS: inflammation of heart
CARDIOMYOPATHY: enlarged, weakened heart, (congestive) heart failure
ANEURYSM: wall of artery weakens
VARICOSE VEINS: usually great or small saphenous veins in legs (hemorrhoids/varices/emboli)
MYOCARDIAL INFARCT
Death of heart muscle from severe blood vessel blockages (ischemia)
Infarct is diagnosed by:1. electrocardiogram (EKG) can detect size & location of infarct
2. enzyme tests for aspartate, creatine, & lactic dehydrogenase
Infarct is treated by:
1 thrombolytic (clot dissolving) agents: streptokinase or TPA (tissue plasminogen activator).
2 anticoagulants to reduce future risks (aspirin, heparin)
HYPERTROPHIC CARDIOMYOPATHY (HCM)
JAMA 2007, joggers 7.6X more likely to die early
Incidence cardiac arrest during exercise 25X higher
HCM: unusual thickening of heart muscle 1:500 with HCM (15 deaths/day) First symptom: death
HCM
POSSIBLE EARLY WARNING SIGNS OF HCM
Chest pain: after a meal Racing heart: panic attack Dizziness or blackout: low alcohol
tolerance Shortness of breath: asthma Unexplained death in family: tragic
accident (<50; falls; drowning, cars)
OBESITY30% Americans overweight30% obese5% very obese
Dangers related to obesity:Cardiovascular
raises LDL + triglycerideslowers HDLraises BPraises blood sugarraises insulindiscourages exercisecontributes to stress + depression
Cancer
52% increase in deaths of males62% increase in deaths of femalesobesity accounts for 14% all cancer deaths in males and 20% in females
Body Mass Index (BMI)
BMI = kg/m2 or lbs/in2*703 Normal BMI: 18-25 Overweight: 25-30 Obese: 30-35 Severely obese: 35-40 Morbidly obese: >40
HEART ATTACK RISK FACTORS
1. DIABETES: high insulin high BP
2. SIMPLE CARBS high insulin
3. ARRYTHMIA atrial fibrillation chaotic heartbeat blood swirls & eddies clots (commonly caused by high BP).
4. CARDIOVASCULAR FITNESS: greatest predictor of death from heart attack. IF heart rate
does not drop at least 25 BPM within one minute of finishing intense workout
CORONARY ARTERY DISEASE (CAD)
Dx: arteriogram catheter into aorta & inject radiopaque dye into coronary arteries (coronary angiogram)
Risk factors for CAD:1 high LDL cholesterol2 high blood pressure leads to enlarged heart;
wear & tear on system; kidney failure
(CONGESTIVE) HEART FAILURE
Heart cannot pump enough blood, so blood backs-up outside of heart; sometimes leads to fluid build-up in other parts of the body e.g. legs or lungs (dropsy)-brain thinks you’re dehydrated
*@ 5 million Americans have heart failure each year*80% over 65 years of age
Symptoms:Shortness of breath; persistent coughing; fatigue; swelling in lower
part of body.Rx: digitalis? (foxglove: whip the tired horse)Prevention involves controlling risk factors: CAD; high BP; high
cholesterol; diabetes.
METABOLIC SYNDROME
1. abdominal obesity (waist circumference greater than 40”[35” for women])2. fasting triglyceride levels of 150 mg/dL or higher3. HDL cholesterol levels below 40 mg/dL (50 for women) {NEJM Jan 2011, quality vs. quantity}4. blood pressure of 130/85 mm Hg or higher5. fasting blood sugar of 110 mg/dL or higher
*presence of any three of above & metabolic syndrome diagnosis
Rx for Metabolic Syndrome1. EXERCISE
a. obesityb. triglyceridesc. HDL cholesterold. blood pressuree. blood sugar
2. WEIGHT LOSSa. eat the right carbs (complex)b. eat the right fats (no sat. or trans)c. eat the best for blood pressure (NA)d. drink with extra caree. shun tobacco
3. MEDICATIONa. drugs for blood pressureb. drugs for blood lipids (LDL) (statins e.g. Lipitor)?c. drugs for blood sugar (Avandia) {hurrah for Big Pharma}d. aspirin (81mg/day)
4. SURGERY (gastric) by-pass superior to banding
HEART SCANS
Electrocardiogram (EKG): records electrical impulses that regulate heart rhythm for deviations from normal.
Nuclear stress test: trace radioactive dye through heart to follow blood flow.
Echocardiagram (ECHO): ultrasound to calculate size, shape, & movements of heart.
Coronary angiogram: “gold standard”, catheter to heart injects dye to highlight arteries (1% serious complications).
CT scan: multiple x-rays with contrast dye in arteries to reveal calcium & fat-filled plaques in arteries (not good in obese or high CA).
PET/CT scan: hybrid of positron emission tomography & CT; use CT to locate narrowed arteries & PET to examine nearby heart muscle for damage.
Magnetic Resonance Imaging (MRI): magnets set nuclei of atoms in heart cells vibrating & they emit radio waves used to create 3-D images of heart.
HEART DISEASE TREATMENT
1. standard by-pass surgery
2. off-pump coronary artery by-pass
3. angioplasty
4. angiogenesis (natural vs. artificial)
5. attack vulnerable plaques
6. germ theory: Chlamydia pneumonia
HYPERTENSION
Dr. Riva-Rocci sphygmomanometer, 1896
High BP stroke, heart attack, kidney failure, atrial fibrillation (a-fib),cognitive impairment,premature death
2003 high BP >120/8065 million Americans high BP59 million pre-hypertension
HYPERTENSION (cont.)BLOOD PRESSURE MEDS
1 thiazide diuretics (hydrochlorothiazide)
2 ACE inhibitors (angiotensin converting-enzyme) {e.g. Vasotec: enalapril}
3 ARBs (angiotensin-receptor blockers) {Cozaar: losatan}
4 calcium-channel blockers {Plendil: felodipine}
5 beta blockers* {Inderal: propanolol}
beta blockers not as good at: decreasing risk for diabetes, strokes, and cardiovascular mortality
>75 anti-hypertensive drugs in 9 categories
HEART ATTACK SYMPTOMS
Men & Women1. pain in ctr. chest or squeezing feeling2. shooting pain or numbness left arm3. sweating & nausea
Women Only1. pain in back or neck2. exhaustion & shortness of breath3. stomach discomfort or indigestion4. feelings of anxiety
MEN’S TOP 10 CAUSES OF DEATH RISK COMPARED WITH WOMEN
1. heart disease 1.82. cancer 1.43. stroke 1.14. pulmonary disease 1.45. injury 2.46. pneumonia/flu 1.57. diabetes 1.28. suicide 4.39. kidney disease 1.510.liver disease 2.3
LIFE EXPECTANCY U.S. 2010 {Japan 86/79}
female 81male 76Overall 79
MALE BIOLOGICAL CLOCK
males >35 twice as likely to be infertile as <25 genetic quality of sperm declines with age 1% decline testosterone/year after 30 this may lead to: decreased muscle mass &
bone mineral density & libido; increased fat; insulin resistance; irritability; dysphoria & maybe diabetes & ED
testosterone replacement may have dangers (Also HRT dangerous for women?)
TOP 5 CAUSES OF DEATH FOR WOMEN, 2004
1. heart disease 332,000
2. stroke 91,000
3. lung cancer 68,000
4. COPD 64,000
5. breast cancer 41,000