Preventing Cardiovascular Disease

1. Preventing Cardiovascular Disease Chapter 2

2. Cardiovascular Disease • the leading cause of death in the U.S.— 37.3% of all deaths • Approximately 25% of Americans have one or more forms of heart or blood vessel disease. • Approximately 330,000 people die annually of coronary heart disease (CHD).

3. The Heart • 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)

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

5. Circulation • 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

6. 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

7. Cardiovascular Disease • 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

8. 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

9. Cardiovascular Disease (2) • Americans as young as 8 have obstructions in their coronary arteries caused by atherosclerosis

10. Stroke (Brain Attack) • Strokes 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 • Strokes have similar risk and prevention factors as heart disease

11. Unchangeable Risk Factors for Heart Disease • 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

12. Major Risk Factors That Can Be Changed • 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

13. Major Risk Factors That Can Be Changed • 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

15. More Risk Factors That Can Be Changed:

16. Blood 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 • An estimated 90% to 95% of hypertension is essential (of unknown origin) • Prehypertension includes blood pressures ranging from 120/80 to 139/89 • Hypertension= 140/90 mmHg

17. Blood Pressure (2) • 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

18. Cigarette Smoking/Tobacco Use • 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

19. Physical 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 • But physical fitness is an important factor in cardiovascular health

20. Physical 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)

22. Obesity • 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

23. Diabetes Mellitus • 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

24. 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

25. Preventable / Changeable Risk Factors: • Cholesterol • Blood Pressure • Cigarette Smoking/Tobacco Use • Physical Inactivity • Obesity • Diabetes Mellitus • Stress

26. Preventing and Reversing Heart Disease Preventing includes: • Exercising regularly • Maintaining an optimal body weight • Practicing sound nutrition • Nonuse of tobacco and other drugs • Nonuse or moderate use of alcohol • Dealing constructively with stress • Periodic medical examinations

27. Preventing and Reversing Heart Disease Reversing includes: • Following a low-fat diet • Stopping tobacco use • Managing stress • Attending support group meetings regularly • Exercising consistently at a moderately intense level

28. Other Risk Factors Other factors include: • Iron-enriched blood • Homocysteine • Lipoprotein • High Sensitivity C-Reactive Protein • Fibrinogin

29. Diagnostic Techniques • Medical examination and patient history • Exercise stress tests • Thallium treadmill test • Echocardiography • Cardiac catheterization

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

31. Preventing Cardiovascular Disease Chapter 2