Preventing Cardiovascular Disease

Cardiovascular disease is the leading cause of death in the U.S.— 42% of all deaths

Approximately 1.5 million heart attacks occur each year—500,000 are fatal

About 50% of people whohave heart attacks wait 2 hours before seeking medical attention

Circulation

The primary function of circulation is to provide a constant supply of blood and nutrients to cells while removing their waste products

Blood is so important to the heart that every muscle fiber is supplied by at least one capillary

Cardiovascular Disease (1)

Coronary heart disease (coronary artery disease; CAD) is diagnosed when any artery is narrowed by 60% or more

A myocardial infarction (heart attack; death of the heart muscle) occurs when blood flow to the heart muscle is disrupted

Most heart attacks occur after age 65, but the process begins as early as adolescence

Myocardial Infarction

The medical term for heart attack is myocardial infarction (MI)

Up to one third of all heart attacks are silent—without obvious signs or symptoms

Silent ischemia, reduced blood flow, can initiate heart attacks without warning

Most heart attacks are obvious

Cardiovascular Disease (2)

Heart disease is an acquired disease that is preventable

Americans as young as 18 have obstructions in their coronary arteries caused by atherosclerosis

Atherosclerosis, characterized by plaque beneath artery linings, is responsible for 80% of CAD deaths in the U.S.

Brain Attack (Stroke)

Brain attacks are caused by a thrombus or an embolus (70% to 80%) or a cerebral hemorrhage

Brain cells die, causing loss of function of some parts of the body

Brain attacks have the same risk factors and prevention factors as heart disease

Unchangeable Risk Factors for Heart Disease (AHA)

Age—80% of fatal heart attacks occur after age 65

Male gender—Heart disease is the leading cause of death for both males and females» Females have a lower rate than males

» Rate is increasing among females, particularly those who smoke and use oral contraceptives

Heredity and Race—A tendency toward heart disease appears to be hereditary

Changeable Risk FactorsCholesterol (1)

A certain amount of cholesterol is necessary for good health

The best way to lower serum (blood) cholesterol is to reduce intake of saturated fat

Saturated fat increases the liver’s production of cholesterol

Changeable Risk FactorsCholesterol (2)

Cholesterol is a steroid that does not dissolve in blood, so it is transported to cells by protein packages

Low-density lipoproteins (LDL), the primary transporters of cholesterol, are the most capable of producing atherosclerosis

People with low blood levels of LDL (less than 100 mg/dl) rarely have heart attacks

Changeable Risk FactorsBlood Pressure (1)

Blood pressure is the force exerted against artery walls as blood travels through the circulatory system

High blood pressure (hypertension) has no signs or symptoms

High BP= 140/90 mmHg

Changeable Risk FactorsBlood Pressure (2)

Long-term uncontrolled hypertension increases the work of the heart, causes it to hypertrophy, and leads to congestive heart failure

Hypertension damages the arteries, accelerates atherosclerosis, and is the most important risk factor for brain attacks

Changeable Risk FactorsTobacco

Cigarette smoking may be the most harmful of the preventable risk factors for chronic illness and premature death

These illnesses include chronic bronchitis, emphysema, strokes, and 87% of all lung cancers

Passive smoking, inhaling the smoke of others, causes the deaths of 38,000 to 43,000 nonsmokers annually

Changeable Risk FactorsPhysical Inactivity

Physical inactivity increases the risk of coronary heart disease by 1.5 to 2.4 times

The greatest health benefits are gained when people expend 1500 to 2000 calories (walk 15 to 20 miles) per week

Exercise for health does not have to be as strenuous as exercise for physical fitness

Changeable Risk FactorsPhysical Inactivity

Physical activity is any physical movement that results in energy expenditure—walking, mowing the lawn, vacuuming

“Every U.S. adult should accumulate 30 minutes or more of moderate intensity physical activity on most, preferably all, days of the week.” (ACSM/CDC statement)

Changeable Risk FactorsObesity

Obesity contributes to about 300,000 deaths per year

Fat that accumulates in the upper half of the body (central abdominal obesity) is significantly more likely to contribute to heart disease

A 5% to 10% weight loss that is maintained can significantly reduce the risk of heart disease

Changeable Risk FactorsDiabetes Mellitus

Diabetes is a metabolic disorder in which the body cannot properly use sugar (glucose) as fuel

Type II (90% of all diabetes) occurs in older, overweight, sedentary adults

Diabetes increases the risk of coronary artery disease 2 to 3 times in men and 3 to 7 times in women

Changeable Risk FactorsStress

Stress elevates heart rate, blood pressure, breathing rate, and blood sugar levels, activates the immune response, and causes other physiological changes

Chronic (long-term) distress significantly strains the body

Prevention of Heart Disease

Prevention includes: Regular exercise Optimal body weight Sound nutritional practices Nonuse of tobacco and other drugs Nonuse or moderate use of alcohol Dealing constructively with stress Periodic medical examinations

Diagnostic Techniques

Medical examination and patient history

Exercise stress tests

Thallium treadmill test

Echocardiography

Cardiac catheterization

Medical Treatment

Low-dose aspirin therapy Coronary artery bypass surgery Balloon angioplasty Coronary stent Artificial valves Left ventricular assist devices Heart transplants