The Healthy Heart Figure 14.1

Chambers of the Heart Left Atrium Receives oxygenated blood from the lungs. Right Atrium Receives blood through the superior and inferior vena cava. Left Ventricle Pumps blood rich in oxygen through the aorta to the arteries to nourish the body systems. Right Ventricle Pumps blood in need of oxygen to the lungs.

Development of Atherosclerosis Fatty Streaks Develop on the Arterial Walls at Injury Spots Growth and Hardening of Fatty Streaks Plaque Formation (well developed by age 30) Narrowing and Loss of Elasticity of the Arteries Restriction of Blood Flow to the Heart or Brain Limited Oxygen Delivery to the Heart or Brain Blood Pressure Elevation Blood Clot Formation and Thrombosis Angina, Heart Attack and/or Stroke Atherosclerosis usually begins with the accumulation of soft fatty streaks along the inner arterial walls, esp at branch points The initiating step in the process of atherosclerosis is some form of injury or inflammation of the arterial wall High BP, high chol levels, cigarette smoking are potential sources of injury Raised LDL chol levels are a sign of high heart attack risk b/c LDLs in the blood tend to deposit cholesterol in the arteries Researchers now theorize that LDL cholesterol is damaging to the artery walls once it has been oxidized Circulating LDL is more likely to settle along the linings of the artery walls after it first reacts with an unstable form of oxygen to become oxidized LDL cholesterol Researchers believe that scavenger cells from the immune system (macrophages) ingest more and more of the oxidized LDL particles and eventually become foam cells These foam cells eventually burst and deposit their accumulated cholesterol as debris in the arterial wall, leading to the development of fatty streaks These fatty streaks gradually enlarge and become hardened with minerals forming plaques Most people have well developed plaques by age 30 The progression of atherosclerosis in the coronary arteries may restrict blood flow to the heart muscle and limit the delivery of oxygen A diet high in saturated fat is a major contributor to the development of plaques and the progression of atherosclerosis Small, cell-like bodies in the blood, known as platelets, cause clots to form whenever they encounter injuries in blood vessels Clots usually form and dissolve all the timein atherosclerosis, clots form faster than they dissolve b/c the platelets respond to plaques as they normally do to injury A blood clot can stick to a plaque in an artery and gradually grow large enough to restrict or close off a blood vessel (thrombosis) A clot may also break free from the artery wall and travel through the circulatory system until it lodges in a small artery and suddenly shuts off flow to the tissues fed by the artery These actions rob the tissue of oxygen and nutrients and the tissue may eventually die When arteries are narrowed by plaques or clots, blood flow is restricted, and the heart must generate more pressure to deliver blood to the tissuesthe higher blood pressure further damages artery walls and plaques and clots are more apt to form at the sites of injuries Heart attack (coronary thrombosis)blocks blood flow through an artery that feeds the heart muscle Stroke or cerebrovascular accident (cerebral thrombosis)blocks blood flow through an artery that feeds the brain

The Atherosclerotic Process Figure 11.7

Blood Pressure the vessels by the blood flowing through them. Definition: A measure of the force exerted against the walls of the vessels by the blood flowing through them. Systolic Blood Pressure Pressure exerted by blood against walls of the arteries during forceful contraction of the heart. Diastolic Blood Pressure Pressure exerted by blood against the walls of the arteries during relaxation of the heart. Sphygmomanometer & Stethoscope

What Is a Healthy Blood Pressure? 115/75 mm Hg HEALTHY READING 120-139/80-90 mm Hg PREHYPERTENSION 140-159/90-99 mm Hg 160+/100+ mm Hg HYPERTENSION

Preventing Hypertension Lifestyle Changes Losing weight. Regular exercise. Dietary Approaches To Stop Hypertension (DASH Diet). Restriction of daily sodium intake.

Risk Factors for Cardiovascular Disease Factors You Can Control Physical Inactivity Tobacco Obesity Blood Fats Metabolic Syndrome Diabetes Mellitus Factors You Can’t Control Heredity Race and Ethnicity Age Gender Bacterial Infection

Tobacco and Heart Disease Smoking is the single most significant risk factor for CV disease and peripheral vascular disease. Each year smoking causes 250,000+ deaths from cardiovascular disease. Active vs. passive smoking. How Smoking Damages The Heart: Nicotine overstimulates the heart. Carbon monoxide reduce the oxygen supply to the heart. Tars and other smoke residues increase the risk of cholesterol build-up in the arteries. Smoking increases blood clotting. Smoking causes irreversible damage to the arteries.

Understanding Blood Lipids Low Density Lipoproteins (LDL) - Fatty substances produced by the liver that carry cholesterol to arterial walls: “bad” cholesterol High Density Lipoproteins (HDL) – Fatty substance that picks up cholesterol in the bloodstream and returns it to the liver; “good cholesterol Triglycerides – Fats that flow through the blood after meals and have been linked to increased risk of coronary artery disease

Serum Cholesterol Guidelines Amount Rating Total Cholesterol <200 mg/dl 200-239 mg/dl >240 mg/dl Desirable Borderline High High Risk LDL Cholesterol Less than 100 mg/dl 100-129 mg/dl 130-159 mg/dl 160-189 mg/dl 190+ mg/dl Optimal Near Optimal High Very High HDL cholesterol >45 mg/dl 36-44 mg/dl <35 mg/dl

The Lifestyle Syndrome Definition: A cluster of conditions and diseases that result from: Consuming too many calories. Ingesting too much saturated fat, sodium, and alcohol. Not burning up enough calories. Smoking or being exposed to tobacco smoke. Consequences: Hypertension, metabolic syndrome, obesity, high cholesterol, cardiovascular disease, cancer, osteoarthritis, depression, sexual dysfunction, and diabetes mellitus.

Unclogging The Arteries Cholesterol-lowering drugs Low-fat diet Dean Ornish Diet (without medications) Very low-fat diet (8% of total daily calories) Moderate exercise for 1 hour three times per week. Stress counseling. One hour of yoga, meditation, breathing, and progressive relaxation per day.

Heart-Smart Strategies For Life Don’t smoke Watch your weight Cut down on saturated fat and cholesterol Get moving Lower your stress levels Know your family history Get your blood pressure checked regularly Tame your temper Get a lipoprotein profile Take appropriate medications