Transcript Chapter 4, Heart

Cardiovascular Health
Objectives:
• Describe the incidence, prevalence and
outcomes of Cardiovascular disease.
• Describe the basic anatomy and physiology
of the heart.
• Describe coronary artery disease and its risk
factors.
• Describe how to prevent and reverse heart
disease.
An Epidemiological Overview of
Cardiovascular Disease, CVD:
• CVD, accounts for 50 % of all diseases and
deaths in the U.S.
• More than 2,600 people die each day from
CVD, 945,000 deaths per year.
• Almost 150,000 die before the age of 65 yrs
• The death rate per 100,000: white men:397
African-Am: 510; white women:286; AfAm women: 397
An Epidemiological Overview of
Cardiovascular Disease, CVD:
• Nearly 61 million Americans live with some
kind of CVD.
• Nearly 13 million have a history of heart
attack, chest pain, or both.
• CVD will permanently disable 19% of the
U.S. labor force.
• The best line of defense is PREVENTION!
Anatomy and Physiology of the
heart:
• The heart is a pump for the blood.
• It beats 60-100 beats per minute, average:
70-80.
• There are four chambers: right atrium, left
atrium, right ventricle, left ventricle.
• There are four valves: tricuspid, mitral,
pulmonic and aortic.
Heart structures:
•
A and P cont’d:
• The heart is self regulating.
• The coronary arteries supply blood to the
heart.
• The vena cavae bring deoxygenated blood
to the heart.
• The pulmonary artery takes deoxygenated
blood from the right ventricle to the lungs
for oxygen.
A and P cont’d:
• The pulmonary veins bring oxygenated
blood from the lungs to the left atrium.
• The aorta takes oxygenated blood to the
body from the left ventricle.
Coronary Heart Disease:
• Also known as Coronary Artery Disease
• The diagnosis is made when there is 60%
occlusion of the coronary arteries.
• This may lead to a heart attack or
myocardial infarction (MI).
• Heart Attacks or MIs produce irreversible
injury and myocardial tissue damage.
Coronary Heart Disease con’d:
• The area of dead tissue can no longer
function as an effective pump.
• Although most heart attacks occur after the
age of 65 years, the dysfunction leading to
them begins well before adolescence,
sometimes as early as childhood
Risk Factors include:
• Lifestyle: inactivity, tobacco
• Environmental influences that increase
one’s susceptibility to disease.
• High blood pressure
• High blood fats
• Age, hereditary, and race
• Obesity
• Male gender
Major risk factors that can be
controlled:
• Cholesterol, smoking, and physical inactivity
• What is cholesterol?
• A steroid, wax type substance that is used for the
building of nerve tissue
• Also used for the construction of cell walls
• It helps with the manufacturing of hormones and
bile (for digestion and absorption of fats).
Some more facts on cholesterol
• Consumption should be limited to 200mg/day.
• Is manufactured by the liver, intestines and arterial
walls
• As cholesterol levels rise, atherosclerotic plaque
forms
• When an injury occurs on the arterial walls (by
tobacco smoke, high blood pressure, elevated
LDLs, diabetes, viral or bacterial infections) the
lumen becomes smaller.
Another controllable risk factor Physical
Inactivity
• Behaviors established in childhood and teenage
years carry into adulthood
• Only 50% pf 12-21 year olds participate in regular
physical activity.
• The percentage of overweight children has
doubled since 1980.
• 61% of overweight 5-10 year olds have one or
more risk factors for cardiovascular disease, 27%
have 2 or more
Risk factor: physical inactivity cont’d:
• Endurance exercises can reduce systolic and
diastolic pressures by 10 points with people
with mild hypertension (above 120/80)
• Resistive or strength training does not seem
to lower blood pressure unless it is
accompanied by aerobic exercises.
Why does exercise lower blood
pressure?
• Contributes to weight loss
• Aerobic exercise reduces resistance to blood
flow in arteries, thus lowering the force
required to circulate blood.
:Risk factors cont’d: Hypertension:
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Weight management
Alcohol (no more than 2oz/day)
Salt restriction
Exercise meditation
Yoga
biofeedback
Another risk factor:
Nicotine:
• Increase LDLs and lowers HDLs
• Causes platelets to aggregate, increases
arterial spasms
• Increases the oxygen requirement of cardiac
muscle
• Constricts blood vessels
• Produces irregular heart rate
Nicotine cont’d:
• Is the causative agent in 30% of heart
disease deaths
• Increases blood viscosity
• Decreases oxygen carrying capacity of red
blood vessels.
• Increases the oxygen requirement of the
heart muscle.
Other possible risk factors: (cutting edge kind of info):
• Iron rich blood
• Homocystine-an amino acid, that is a
building block for protein, yet if it is not
broken down it can lead to a higher risk for
heart disease.
• Lipoprotein- a “bad” cholesterol
• High sensitivity C-reactive protein, a test
that indicates inflammation
• Fibrinogen-increases thickness of blood.
Preventing and reversing heart
disease:
• Besides everything we have discussed…
• Dr. Dean Ornish showed that a program
consisting of yoga, low fat diet, smoking
cessation and support groups decrease
atherosclerosis.
Treating coronary artery
occlusion,balloon angioplasty:
• Balloon angioplasty
• Coronary stent-metallic tube
• Coronary bypass surgery
Coronary Artery Bypass:
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Coronary Stent-metallic tube:
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Summary on Heart Attacks:
• 1/3 are silent, with no signs or symptoms
• Symptoms when present include: chest
pain radiating to the left side of the jaw,
nausea
• Warning sign: angina pectoris
• Diagnosis: EKG, enzymes, clinical
presentation
Other types of C VD:
• Angina (pectoris)
• Arrhythmias
• Congenital rheumatic
heart disease
* Stroke
* congestive
heart failure
Summary on how to manage risk factors
for CVD:
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Avoid tobacco
Cut down on cholesterol
Maintain healthy weight
Manage stress
Exercise regularly
Eat low fat, low salt diet
Control blood pressure