Cardiovascular Health Chapter 12

Cardiovascular System and How it Works: Blood Red blood cells (carry oxygen) Plasma (transports gases) Platelets (clotting factor) White blood cells (protect body from infection) Cardiovascular System and How it Works: Blood

Cardiovascular System and How it Works: Blood Vessels Carry blood away from the heart Branch into smaller blood vessels called arterioles, which branch into smaller vessels called capillaries Arteries Permeate tissues Allow substances such as nutrients and oxygen to move out of blood and waste products and carbon dioxide to move into blood Capillaries Return blood to the heart Have thinner walls than arteries Have one-way valves which help prevent the back-flow of blood Veins Cardiovascular System and How it Works: Blood Vessels

The Major Arteries of the Body - The heart is located to the left of the midline in the chest cavity. - The arteries take blood away from the heart and are shown in red. - Veins return blood to the heart and are shown in blue.

Cardiovascular System and How it Works: Heart Four chambers Two atria Two ventricles Coronary arteries supply heart with blood

Cardiovascular System and How it Works: Blood Vessels Coronary arteries Arise from the base of the aorta Bring freshly oxygenated blood to heart muscle The left and right coronary arteries are the two main coronary arteries. Branch into multiple arteries that supply the entire heart with blood

Cardiovascular Diseases Hypertension (chronic high blood pressure) Stroke (blood vessel disease of the brain) Rheumatic heart disease Atherosclerosis (blood vessel disease) Coronary artery disease and stroke result from atherosclerosis

Cardiovascular Disease: Atherosclerosis Plaques (fatty deposits) develop inside arteries. May begin with an injury to the artery lining Lipids, especially cholesterol, accumulate at injury sites and cling to the interior of the blood vessel walls. Scar tissue forms and calcium is deposited, hardening the artery. Blood clots sometimes develop at this site. Blood clots are often the cause of heart attack or stroke. Incidence increases with age. Not all elderly have extensive plaques and some young people do.

Cardiovascular Disease: Coronary Artery Disease (CAD) Blocked coronary arteries Result in heart attack Angina pectoris (chest pain) One out of every three Americans has one or more forms of CVD. In CAD, coronary vessels become partly or completely blocked by plaque and/or blood clots. Peripheral blood vessel disease—blockages occurring in organs and tissues other than the heart

Cardiovascular Disease: Coronary Artery Disease (CAD) Blockage or spasm reduces blood flow to heart muscle and results in angina pectoris. Angina is felt beneath the breastbone and extends into left shoulder and down left arm. May also be felt in jaw, neck, or back Angina pain is described as aching, squeezing, burning, heaviness, or pressure. Thrombus—stationary blood clot; can block blood vessel where it forms. Coronary thrombosis—the development of a thrombus that blocks a coronary artery Embolus—floating blood clot; forms and floats until it blocks a blood vessel downstream Coronary embolism—produced when an embolus blocks a coronary artery downstream from where it was formed

Cardiovascular Disease: Heart Attack One-third to one-half of people with CAD are stricken suddenly and unexpectedly with a heart attack (myocardial infarction). An infarction is an area of tissue that dies due to insufficient blood flow and lack of oxygen. Arrhythmias Heart failure Cardiac arrest Death Cardiovascular Disease: Heart Attack

Cardiovascular Disease: Heart Attack Congestive heart failure Heart cannot pump effectively and veins bringing blood to the heart become overfilled with blood. Causes include CAD, heart defects, and rheumatic heart disease. Primary signs and symptoms are shortness of breath, retention of fluid, congestion of lungs, and fatigue.

Cardiovascular Disease: Heart Attack Cardiac arrest May occur as a result of heart attack Heart suddenly stops beating Immediate defibrillation is needed to avoid death. About 380,000 persons in the United States experience sudden cardiac death each year.

Cardiovascular Disease: Heart Attack Signs and Symptoms Pressure or heaviness in the chest Shortness of breath Profuse sweating Weakness Anxiety Nausea Cardiovascular Disease: Heart Attack Signs and Symptoms

Cardiovascular Disease: Stroke A stroke occurs when arteries that supply brain become blocked, preventing blood flow. May also occur if a blood vessel in the brain bursts (cerebral hemorrhage) Aneurysm—swollen, weakened blood vessel; may rupture

Cardiovascular Disease: Stroke Signs and Symptoms Weakness, numbness, or paralysis on one side of the body Loss or dimming of vision Loss of speech or difficulty speaking or understanding speech Sudden severe headache Sudden dizziness, unsteadiness, or episodes of falling Cardiovascular Disease: Stroke Signs and Symptoms

Risk Factors for Cardiovascular Disease Modifiable Unmodifiable Cigarette smoking Obesity Chronic high blood pressure Sedentary lifestyle Diabetes mellitus Anxiety and stress Abnormal blood lipids Male gender Increasing age Family history of cardiovascular disease

Risk Factors for Cardiovascular Disease: Blood Lipids Helps remove cholesterol from the body High levels of HDL lower risk of CAD HDL or “good” cholesterol Carries cholesterol to the cells, including those that line arteries High levels of LDL raise risk of CAD LDL or “bad” cholesterol Risk Factors for Cardiovascular Disease: Blood Lipids

Risk Factors for Cardiovascular Disease: Cigarette Smoking Significantly increases the risk of heart attack and stroke (2 to 4 times) Tend to have reduced HDL levels and increased LDL Tend to have increased levels of clotting factors Compounds in cigarette smoke damage blood vessels, leading to atherosclerosis. Risk Factors for Cardiovascular Disease: Cigarette Smoking

Risk Factors for Cardiovascular Disease: High Blood Pressure Normal pressure is less than 120/80 mm Hg. Systolic BP—pressure exerted on artery walls when the heart’s left ventricle contracts Diastolic BP—pressure exerted on artery walls when left ventricle relaxes Prehypertension—systolic pressure reading between 120 and 139 or diastolic pressure is between 80 and 89 Stage 1 hypertension—systolic reading between 140 and 159 or a diastolic reading of 90 to 99 Stage 2 hypertension—systolic reading of 160 or more or a diastolic reading of 100 or more Persistently high arterial blood pressure contributes to the development of atherosclerosis. Risk Factors for Cardiovascular Disease: High Blood Pressure

Risk Factors for Cardiovascular Disease: Physical Inactivity 150 minutes/week of physical activity lowers the risk of heart disease and stroke. More than 50% of American adults do not get enough physical activity; 25% are not active at all during leisure time. Sedentary people are twice as likely to develop CAD as active people. Risk Factors for Cardiovascular Disease: Physical Inactivity

Risk Factors for Cardiovascular Disease Obesity Obesity doubles the risk of CAD; even being mildly overweight increases this risk. Diabetes mellitus Elevated blood glucose levels damage heart muscle, small coronary arteries, and major arteries. Atherosclerosis occurs more frequently and at an earlier age in diabetics, especially women. Anxiety and stress Stress can result in spasms of the coronary arteries, which can contribute to angina attacks. People with anxiety disorders are 2–6 times as likely to die from a heart attack as people without. Elevated C-reactive protein An elevated blood level C-reactive protein can be a positive risk factor for CVD.

Maintaining Cardiovascular Health Refrain from smoking. Maintain a healthy weight. Exercise regularly. Maintain healthy blood pressure levels. Maintain healthy blood cholesterol levels. Eat less fat and more fiber, practice relaxation, and reduce sodium intake as necessary.