Preventing Cardiovascular Disease

Chapter 2

• Leading cause of death in the U.S.— 35.3% of all deaths

• Approximately 25% of Americans have one or more forms of heart or blood vessel disease. (80 Million People)

Cardiovascular Disease

• Approximately 445,687 people die annually of coronary heart disease (CHD).

• Cardiovascular disease rare 100 years ago

• Reached epidemic proportions during the middle 20 century

• 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 problems leading up to them begin as early as adolescence

Cardiovascular Disease

Cardiovascular Disease

• Slow progressive inflammatory disease of the arteries characterized by the deposition of plaque beneath the lining of the artery

• Americans as young as 8 have obstructions in their coronary arteries caused by atherosclerosis

• Consists of cardiac muscle

• Weighs 8 to 10 ounces

• Has two halves (pumps)

• Divided by the septum

• Halves are divided into upper chambers (atria) and lower chambers (ventricles)

The Heart

• The left side of the heart (systemic pump) receives the oxygenated blood from the lungs and pumps it to all the tissues in the body

• The right side of the heart (pulmonary pump) receives deoxygenated blood from the body and pumps it to the lungs

Circulationprovides constant supply of blood and nutrients to cells while removing waste products

• The heart has its own conduction system

• The beating rate and rhythm are established by the sinoatrial (SA) node (pacemaker)

• The electrical contraction pauses at the atrioventricular (AV) node, allowing the ventricles to fill with blood

CIRCULATION

• The heart is supplied with blood from coronary circulation after it has been ejected from the heart

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

CIRCULATION

• 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

Myocardial InfarctionMedical term for heart attack

• Strokes are caused by: a thrombus, an embolus (70% to 80%), a cerebral hemorrhage

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

• Strokes have similar risk and prevention factors as heart disease

• Full blown strokes may be preceded by transient ischemic attack (TIA) “mini strokes”

• Produce stroke-like symptoms, temporary, and usually no lasting damage

• People who have one or more TIA more likely to suffer stroke

Stroke

• Age

• 55% of 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 & Race

• Family history of cardiovascular disease

• African Americans have high incidence of hypertension

• Mexican Americans, Native Americans, Nativre Hawiaiians & some Asians Americans have high rate of CVD because of obesity

Uncontrollable Risk Factors forHeart Disease

CONTROLLABLE RISK FACTORS

• Cholesterol• Blood Pressure• Cigarette Smoking/Tobacco Use• Physical Inactivity• Obesity• Diabetes• Stress

Preventable/Changeable Risk Factors:

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

• 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

CHOLESTEROL

• 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

• Cigarette smoke, lack of exercise, hypertension, high cholesterol, excessive weight, unhealthy diet, and rapid heart rate result in continued inflammation and growth of plaque

• High–density lipoproteins (HDL) are invoved in reverse transport of cholesterol – transfer to liver

• Cholesterol removed from the blood helping to prevent and reduce plaque

CHOLESTEROL

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

• Recorded in millimeters of mercury (mmHg)

• High blood pressure (hypertension) has no signs or symptoms

• An estimated 90% to 95% of hypertension is essential (of unknown origin)

• Approximately 73,600,000 American adults have hypertension

• Prehypertension includes blood pressures ranging from 120/80 to 139/89

• Estimated that 56,600,000

• Hypertension= 140/90 mmHg

Blood Pressure

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

• Hypertension is the most important risk factor for strokes

• Treatment include some or all of the following:

• Weight loss

• Salt and alcohol restriction

• Adequate intake of calcium, potassium, & magnesium

• Relaxation Techniques

• Exercise

• medications

Blood Pressure cont’d

• Cigarette smoking is considered to 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

• Loss of life from smoking represents a life expectancy drop of ~18%

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

Tobacco Use

• Harmful products in cigarettes

• Nicotine

• Carbon monoxide

• Poisonous gases, tars, chemical additives

• Harmful effects of smoking are insidious and take time to appear

• Quitting is vital

• Smoking increases the risks for many chronic diseases

• Smoking encourages the accumulation of visceral fat (abdominal fat)

• Visceral fat leads to a constellation of risk factors called the metabolic syndrome or insulin-resistance syndrome

Tobacco Use cont’d

• 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• But physical fitness is an important factor in cardiovascular

health

Sedentary Lifestyle

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

• Sedentary death syndrome (SeDS) created to illustrate the burgeoning lists of health disorders that are exacerbated by a lack of physical activity

• Relates to 23 diseases

• Elevated blood fats, Type II diabetes, hypertension, heart disease, obesity, osteoporosis, resting tachycardia, etc.

• “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)

Sedentary Lifestyle cont’d

•Obese people who have no other risk factors are still more likely to develop heart disease or stroke.

•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

•Obesity among children and teenagers has been increasing the last few decades

Obesity

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

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

• It is being seen more and more in children, adolescents, and young adults

• Diabetes increases the risk of coronary artery disease 2 to 4 times that of non-diabetics

Diabetes

• 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

Stress

•Distress - negative stress

•Eustress - positive stress

• Exercising regularly

• Maintaining an optimal body wt

• Practicing sound nutrition

• Nonuse of tobacco and other drugs

• Nonuse or moderate use of alcohol

• Dealing constructively with stress

• Periodic medical examinations

PREVENTING HEART DISEASE INCLUDES:

• Following a healthy diet

• Stopping tobacco use

• Managing stress

• Exercising consistently at a moderately intense level

REVERSING HEART DISEASE INCLUDES:

• Medical examination and patient history

• Exercise stress tests

• Thallium treadmill test

• Echocardiography

• Cardiac catheterization

Diagnostic Techniques

• Low-dose aspirin therapy

• Coronary artery bypass surgery

• Balloon angioplasty

• Coronary stent

• Artificial valves

• Left ventricular assist devices

• Heart transplants

Medical Treatment