Cardiovascular Health

1. Cardiovascular Health Chapter 15

2. Introduction • Cardiovascular disease (CVD) • Leading cause of death in the U.S. • Affects nearly 81 million Americans • Claims one life every 38 seconds • About 2,300 Americans die every day • CVD is largely due to our way of life

3. The Cardiovascular System • Consists of the heart and blood vessels • With lungs, known as the cardiorespiratory system • The Heart • Four-chambered, fist-sized muscle located just beneath the sternum • Blood travels through two separate circulatory systems: • Pulmonary circulation • Right side of heart pumps blood to lungs. • Systemic circulation • Left side of heart pumps blood through the rest of the body • Path of blood flow: • Through venae cavae into atrium (right upper chamber) • From atrium to ventricle (right lower chamber) • Pulmonary artery to the lungs • In lungs, picks up oxygen and discards carbon dioxide • Through pulmonary veins into heart’s left atrium • Left atrium fills, pumps blood into left ventricle • When left ventricle full, pumps blood through aorta fordistribution to the rest of the body’s blood vessels

4. Cardiovascular System (continued) • Systole • The heart’s contraction • Diastole • The period of relaxation • Blood pressure • Force exerted by blood on the walls of the blood vessels, created by pumping action of the heart • Heartbeat • Controlled by nerve impulses

5. Cardiovascular System (continued) • Blood Vessels (classified by size and function) • Veins • Carry blood to the heart • Thin walls • Arteries • Carry blood away from the heart • Thick elastic walls expand and relax with the volume of blood • Coronary arteries • Two large vessels that supply blood to the heart • Capillaries • Smallest arteries, only one cell thick • Venules • Blood empties from capillaries into venules that connect to veins that return the blood back to the heart • 150-pound person has about 5 quarts of blood that circulates about once each minute

6. Risk Factors for Cardiovascular Disease • Two categories of increased risk for CVD • Major risk factors • Contributing risk factors • Controllable aspects of lifestyle that can be changed • Major risk factors that can be changed • American Heart Association identifiedsixmajor risk factors. • Tobacco use • High blood pressure • High cholesterol • Physical inactivity • Obesity • Diabetes

7. Tobacco Use • 1 in 5 deaths from CVD is a smoker • Smokers have 2 to 3 times higher risk of death from a heart attack than do nonsmokers • Smoking doubles risk of stroke • Damages the lining of arteries • Reduces HDL (“good” cholesterol) • Raises triglycerides and LDL • Nicotine increases blood pressure and heart rate • CO displaces O2 • Causes platelets to become sticky and increases blood thickness • Speeds the development of fatty deposits in the arteries

8. High Blood Pressure • Hypertension • Too much pressure against blood vessel walls • Short periods of high blood pressure are normal, but chronic high blood pressure is a health risk • Atherosclerosis • Heart has to work harder, weakens, enlarges, arteries narrow, scar, and harden • About 33% (73 million) of adults have hypertension • 37% of adults have prehypertension • Test your blood pressure at least once every two years

9. Table 15.1 Blood Pressure Classification for Healthy Adults

10. High Cholesterol • Fatty, waxlike substance that circulates through the bloodstream • Important component of: • Cell membranes • Sex hormones • Vitamin D • Fluid that coats the lungs • Protective sheaths around nerves • Excessive cholesterol clogs the arteries • Increased risk of CVD • Good versus bad cholesterol • Low –density lipoproteins (LDL) (“bad” cholesterol) • Shuttle cholesterol from the liver to organs and tissues • High-density lipoproteins (HDL) (“good” cholesterol) • Shuttle unused cholesterol back to the liver for recycling • By removing cholesterol from blood vessels, HDL helps protect against atherosclerosis • Recommended blood cholesterol levels • Benefits of controlling cholesterol

11. Table 15.2 Cholesterol Guidelines

12. Physical Inactivity • 40-60 million Americans are so sedentary that they are at high risk for developing CVD • Exercise reducesrisk • Closest thing we have to a magic bullet against heart disease • Controls blood pressure and resting heart rate • Lowers LDL • Increases HDL • Maintains weight • Improves the condition of blood vessels • Helps prevent or controls diabetes

13. Obesity • Risk of death from CVD is two to three times more likely in obese people (BMI ≥ 30) • Increased strain on the heart • Strongly associated with: • Hypertension • High cholesterol • Insulin resistance • Diabetes • Physical inactivity • Increasing age • Endothelial cell dysfunction • Coronary arteries constrict instead of dilate • Hypertrophy (ventricular enlargement)

14. Diabetes • Doubles the risk of CVD for men • Triples the risk of CVD for women • Loss of 5-10 years off your life • Higher risk • Hypertension • Obesity • Unhealthy blood lipid levels • Elevated blood glucose and insulin can damage the endothelial cells lining the arteries • More vulnerable to atherosclerosis

15. Contributing Risk Factors that Can Be Changed • High triglyceride levels • Blood fats that are a reliable predictor of heart disease • Psychological and social factors • Stress • Chronic hostility and anger • Suppressing psychological distress • Depression • Anxiety • Social isolation • Low socioeconomic status • Alcohol and drugs

16. Major Risk Factors that Cannot Be Changed • Heredity • CVD has genetic component; high cholesterol levels, hypertension, diabetes, and obesity • Aging • Over the age of 65 • Being male • Men have higher risk earlier in life • Ethnicity • African Americans higher risk of hypertension; Hispanics greater risk of HBP and angina; Asians lower rates of CVD

17. Possible Risk Factors Currently Being Studied • Insulin resistance and metabolic syndrome • Homocysteine • Amino acid circulating in the blood • Infectious agents • Chlamydia pneumoniae – flulike respiratory infections • Lipoprotein(a) – Lp(a) • Strong genetic component • LDL particle size • Particles differ in shape and size • Blood viscosity (thickness) and iron • Uric acid • Time of day and time of year • More heart attacks and sudden death occur between 6:00AM and noon • 50% more occur in winter months than in summer months

18. Major Forms of Cardiovascular Disease • Atherosclerosis - narrowed by fatty deposits • Plaques accumulate in artery walls • Coronary heart disease (CHD) • Coronary artery disease (CAD) • Peripheral arterial disease (PAD) • Heart attack – heart tissue is damaged and part of it may die from lack of blood • Myocardial infarction (MI) • American Heart Association • 785,000 people have a first heart attack each year • 470,000 people have recurrent attack • 195,000 people suffer a symptomless or “silent” heart attack each year

19. Table 15.5 Deaths from Acute Myocardial Infarction, 2007

20. Symptoms of a Possible Heart Attack • Chest pain or pressure • Arm, neck, or jaw pain • Difficulty breathing • Excessive sweating • Nausea and vomiting • Loss of consciousness

21. Heart Disease and Heart Attack • Angina – arteries narrowed by disease, but under stress heart cannot receive enough oxygen • Angina pectoris • Usually felt as an extreme tightness in the chest and heavy pressure behind the breastbone or in the shoulder, neck, arm, hand, or back • Arrhythmias and sudden cardiac death – electrical conduction system is disrupted • Sudden cardiac death (cardiac arrest) often caused by an arrhythmia called ventricular fibrillation

22. Helping a Heart Attack Victim • Most victims die within 2 hours from initial symptoms • Give one adult aspirin tablet (325 mg) • Cardiopulmonary resuscitation (CPR) • Refer to Take Charge box “What to Do in Case of a Heart Attack, Cardiac Arrest, or Stroke”

23. Detecting and Treating Heart Disease • Electrocardiogram (ECG or EKG) • Electron-beam computed tomography (EBCT) • Echocardiography – sound waves • Multi-slice computed tomography (MSCT) • Magnetic resonance imaging (MRI) • Nuclear myocardial perfusion imaging • Positron Emission Tomography (PET) • Angiogram • Balloon angioplasty • Coronary bypass surgery

24. Stroke or Cerebrovascular Accident (CVA) • 2 million brain cells die per minute during a stroke • Ischemic stroke – blockage in a blood vessel • Thrombotic stroke - clot forms in a cerebral artery • Embolic stroke - wandering blood clot • Hemorrhagic stroke - blood vessel ruptures in the brain • Intracerebral hemorrhage • Subarachnoid hemorrhage • Aneurysm

25. Figure 15.5 Types of Stroke

26. The Effects of a Stroke • Interruption of the blood supply to any area of the brain prevents the nerve cells from functioning, in some cases causing death • Usually suffer some lasting disability • Paralysis • Walking disability • Speech impairment • Memory loss • Changes in behavior

27. Detecting and Treating Stroke • Prompt recognition of symptoms: • Sudden numbness or weakness of face, arm, leg, or one side of the body • Loss of speech or difficulty speaking • “Three Simple Ways to Recognize a Stroke” • Ask the person to smile. If her smile droops on one side, or if she is unable to move or open one side of her mouth, she may be having a stroke. • Ask the person to hold his arms out. If the person cannot move one arm or hold one arm still, it may be a sign of a stroke. • Ask the person to repeat a simple sentence, such as “Take me out to the ball game.” If she has trouble speaking or cannot speak, a stroke is possible.

28. Detecting and Treating Stroke • Transient ischemic attack (TIA) • Temporary stroke-like symptoms (ministroke) • Computed tomography (CT) • MRI • Ultrasound • Drugs • Carotid endarterectomy surgery – plaque is removed from the artery • Rehabilitation • Physical therapy • Speech and language therapy • Occupational therapy

29. Peripheral Arterial Disease (PAD) • PAD – atherosclerosis in the leg (or arm) arteries, which can limit or block the blood flow • Patients typically also have coronary artery disease • About 8 million people in the U.S. have PAD • Risk factors: • Smoking • Diabetes • Hypertension • High cholesterol • Symptoms • Claudication (aching or fatigue in the affected leg) • Rest pain (limb artery cannot supply enough blood at rest)

30. Congestive Heart Failure • Number of conditions • High blood pressure • Heart attack • Atherosclerosis • Alcoholism • Viral infections • Rheumatic fever • Birth defects • Pulmonary edema - fluid accumulates in the lungs • Heart can not maintain regular pumping rate; fluid backs up • Controlled by: • Reducing cardiac load • Eliminating excess fluid • Restriction of salt • Drug therapy

31. Other Forms of Heart Disease • Congenital heart defects • Malformation of the heart or major blood vessel • Hypertrophic cardiomyopathy (HCM) • Occurs in 1 out of 500 people • Most common cause of sudden death in athletes younger than 35 • May be identified by a murmur • Rheumatic heart disease • Streptococcal infections cause damage to the heart muscle and valves • Strep throat needs to be treated • Heart valve disorders • Congenital heart defects and certain types of infections • Mitral valve prolapse

32. Protecting Yourself Against CVD • Eat heart-healthy • Decrease fat and cholesterol • Total fats less than 30% of total calories • Low saturated fats • Increase fiber intake • Decrease sodium intake and increase potassium intake • Moderation of alcohol

33. Other Dietary Factors • Omega-3 fatty acids • Plant stanols and sterols • Folic acid • Vitamins B-6 and B-12 • Calcium • Soy protein • Healthy carbohydrates • Total calories • DASH • Dietary Approaches to Stop Hypertension

34. Protecting Yourself • Moderate physical activity • Avoid tobacco • Know and manage your blood pressure (monitor once every two years) • Know and manage your cholesterol levels • Develop effective ways to handlestress and anger

35. Figure 15.6 Strategies for Reducing Your Risk of CVD

36. Cardiovascular Disease Chapter 15