Transcript Cardiovascular Disease Cardiovascular Disease

Cardiovascular
Disease
Cardiovascular Disease
• The number one cause of death in the
United States
• Caused the death of over 900,000
Americans each year
• Economic cost of over $351 billion
dollars
• Since 1960, a gradual decline in
morbidity and mortality due to
cardiovascular disease
The Leading Causes of Death
From Cardiovascular Disease
Data from American Heart Association, 2006.
Factors Contributing
to Decline in Deaths
• Improved public awareness (e.g., concept of risk
factors)
• Increased use of preventive measures, including
lifestyle changes
• Better and earlier diagnosis
• Improved drugs for specific treatment
• Better emergency and medical care
Your risk for developing
cardiovascular disease is
reduced when you don’t
smoke, get regular exercise,
eat well, maintain a healthy
body weight, and manage
stress.
Anatomy and Function of the
Cardiovascular System
Cardiovascular Diseases
•
•
•
•
•
•
Coronary artery disease (CAD)(CHD)heart
Hypertension
Stroke
Heart failure
Peripheral vascular disease
Valvular, rheumatic, and congenital heart disease
Heart Attack
• Coronary thrombosis or
myocardial infarction
• Lack of blood flow or supply
to areas of the heart
Coronary Artery Disease
Coronary artery disease (CAD): involves
atherosclerosis in the coronary arteries
Atherosclerosis: progressive narrowing of the arteries
due to plaque formation
Ischemia: a deficiency of blood flow to the heart
caused by CAD
Angina pectoris: chest pain
Myocardial infarction: a heart attack due to ischemia
leading to irreversible damage and necrosis
Blood Flow Blockage in the Coronary Arteries
Warning signs of a heart attack
include uncomfortable pressure or
pain in the center of the chest that
lasts 2 minutes or longer; pain that
spreads to the shoulders, neck or
arms; or severe pain, dizziness,
fainting, sweating, nausea, or
shortness of breath. If you
experience any of these signs, you
should seek medical help
immediately.
Percentages of the U.S. Population at
Increased Risk for Coronary Artery
Disease Based on Primary Risk Factors
Reproduced from Caspersen, C.J.: Physical activity and coronary heart disease. Physicians Sportsmedicine 1987;
15(11): 43-44.
Atheresclerosis
Angina Pectoris
• Chest pain
• Lack of blood flow and oxygen
to areas of the heart
• Increased risk of heart attack
Other Types of
Cardiovascular Disease
• Congenital heart defects—abnormal
heart structures, vessels, and valves
at time of birth
• Rheumatic heart disease—bacterial
infection of the heart that damages
heart valves
• Congestive heart failure—condition
that occurs when other diseases have
damaged the heart and limited its function
(continued)
Other Types of
Cardiovascular Disease
• Bacterial endocarditis—infection of the
lining or valves of the heart
• Aneurysms—a weakness or bulge in
an artery that can burst and lead to
massive internal bleeding(動脈瘤)
Risk Factors for CHD
Major alterable
Major unalterable
Contributing
Hypertension
Age
Stress
Tobacco smoking
Genetics
Excessive
alcohol
Cholesterol
Gender
Physical inactivity
Obesity
Diabetes
Major Unalterable Risk
Factors for CHD
• Heredity—family history and race
• Gender—males are at higher risk
• Age—increased age relates to
increased risk
Hypertension
• About one in every three adult Americans has
hypertension
• Causes the heart to work harder
• Strains the systemic arteries and arterioles
• Can lead to atherosclerosis, heart attacks, heart failure,
stroke, and renal failure
Reducing the Risk of Hypertension
Through Exercise
• People who are active and those who are fit have
reduced risk for developing hypertension
• Resting blood pressure decreases by training in
people with hypertension(aerobic and endurance ex)
Controllable Risk Factors
for Hypertension
•
•
•
•
•
•
•
Insulin resistance
Obesity and overweight
Diet (sodium, alcohol)
Use of oral contraceptives
Use of tobacco products
Stress
Physical inactivity
Pathophysiology of Hypertension
More than 90% of people with hypertension have
essential hypertension
Risk factors
– Heredity, including race
– Increasing age and male sex
– Sodium sensitivity
– Excessive alcohol consumption and use of tobacco
products
– Obesity and overweight
– Diabetes or insulin resistance
– Physical inactivity
– Oral contraceptives
– Pregnancy
– Stress
High Blood Cholesterol
• Cholesterol is a fatlike substance found
in the body’s cells and bloodstream.
• The body produces cholesterol primarily
through the liver; we also consume
cholesterol through our diet.
• Two types relevant to CHD are high
density lipoprotein (HDL-C) and low
density lipoprotein (LDL-C).
• HDL-C decreases the risk of CHD.
• LDL-C increases the risk of CHD.
Americans with High Cholesterol
Standards for Cholesterol
Total Cholesterol (TC)
Desirable: less than 200mg/dl
Borderline high: between 200 and 239mg/dl
High: 240mg\dl or higher
LDL-C
Optimal: less than 100mg/dl
Borderline high: between 130 and 159mg/dl
High: between 160mg/dl and 189mg/dl
HDL-C
Low: less than 40mg/dl
The Cholesterol Ratio
Cholesterol ration = TC ÷ HDL - C
Example: TC = 140, HDL - C = 40
Cholesterol Ratio = 180 ÷ 40 = 4.5
The American Heart Association
recommends a cholesterol ratio of less
than 3.5.
The Cholesterol Ratio and Risk of CHD
Your total cholesterol level
should be below 200
milligrams per deciliter of
blood. Your LDL-C count
should be less than 130
milligrams per deciliter. It’s
desirable that your ratio of
total cholesterol to HDL-C
be 3.5 or less.
Other Major Risk
Factors for CHD
• Smoking—doubles the risk for CHD
• Diabetes—inability to control blood
levels increases the risk of CHD
• Obesity—related to many health
problems and greatly increases the
risk of CHD
Physical Inactivity:
A Major Risk Factor for CHD
• In 1992, the American Heart Association
classified physical inactivity as a major
risk factor for CHD.
• Low levels of physical activity and
cardiorespiratory fitness can double the
risk of CHD.
There are a number of CHD risk
factors that you can control: high
blood pressure, high blood
cholesterol, elevated
triglycerides, smoking, diabetes,
excessive fat, and physical
inactivity. Inactive people are
twice as likely as active people to
die from cardiovascular disease.
Contributing Risk
Factors for CHD
• Excessive and prolonged stress can
increase the risk of CHD.
• Personality traits of anger and hostility
can increase the risk of CHD
• Excessive use of alcohol
Epidemiological Evidence
• Physical inactivity doubles the risk of CAD
• Low-intensity physical activity is sufficient to reduce the
risk of this disease
• Health benefits do not require high-intensity exercise
• More vigorous exercise likely provides even greater
benefits
Physical Activity vs. Physical Fitness
Dose–Response Curve
Reprinted, by permission, from P.T. Williams, 2001, "Physical fitness and activity as separate heart disease risk
factors: A metaanalysis," Medicine and Science in Sports and Exercise 33: 754-761.
Aerobic Training Adaptations
• Produce larger coronary arteries which increases the
capacity for blood flow to the heart
• Increased cardiac pumping capacity
• Improved collateral circulation in the heart
• Improved endothelial function
• Reduce blood pressure (~7 mmHg) in individuals with
mild to moderate hypertension
• Improves cholesterol ratio
• Weight reduction
• Improves insulin sensitivity
• Stress management
Comparison of the Left Main Coronary
Artery in (a) Sedentary and (b) Exercising
Monkeys on Atherogenic Diets
Stroke: Brain Attack
• Cerebral thrombosis—blockage of
blood flow to the brain.
• Cerebral hemorrhage—bursting of an
aneurysm or a blow to the head that
cause bleeding into the cranium.
The severity of a stroke relates to the
amount of brain tissue affected.
Risk Factors for Stroke
Unalterable
• Heredity—Family history and race.
African-Americans have a much higher
risk of stroke than white Americans do.
• Gender—Males have a higher risk
than females.
• Age—As age increases the risk of
stroke increases.
Risk Factors for Stroke
Alterable
• Hypertension—The major risk factor
for stroke.
• Smoking
• History of transient ischemic attacks
(ministrokes)
• High red blood cell counts
Risk Factors for Stroke
Contributing
• High blood cholesterol and triglycerides
• Physical inactivity
• Obesity