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