blood circulationcontrollable and uncontrollable risk factorsdiscuss the major cardiovascular diseasepulmonary circulation – circulation of blood between the heart and lungs; controlled by right side of the heartsystemic circulation – circulation of blood between the heart and rest of the body; controlled by left side of the heartatrium (pl. atria) – upper chambers of the heartventricle – lower chambers of the heartvena cava (pl. venae cavae) – large veins through which blood is returned to right atriumaorta – body’s largest artery; receives blood from left ventricle and distributes to the bodysystole – contraction phase of the heart; blood leaves the heart; BP increase; top number in BP readingdiastole – relaxation phase of the heart; blood enters the heart; BP decrease; bottom number in BPvein – carries blood to the heart (deoxygenated blood in systemic circulation, oxygenated blood in pulmonary); thinner wallsartery – carries blood away from the heart (oxygenated blood in systemic circulation, deoxygenated blood in pulmonary); thicker, elastic walls that expand/relax with the volume of bloodcoronary artery – system of arteries branching from the aorta that supplies blood to the heart musclecapillaries – tiny vessels only one cell thick; deliver oxygen and nutrient-rich blood to the tissues and pick up oxygen-poor, waste-laden blood for returnplatelets – cells in the blood that are necessary for formation of blood clotslow-density lipoprotein (LDL) – contains a moderate amount of protein and a large amount of cholesterol, which tends to become deposited on artery walls, increasing the risk of CVD; considered “bad” cholesterolhigh-density lipoprotein (HDL) – contains relatively little cholesterol that helps transport cholesterol out of the arteries, protecting against CVD; considered “good” cholesterolhypertrophy – abnormal enlargement of an organangina pectoris – pain in the chest, and often in left arm and shoulder, usually brought on by exercise or stress; caused by heart muscle not receiving enough bloodarrhythmia – a change in the heartbeat’s normal patternsudden cardiac death – a nontraumatic, unexpected death from sudden cardiac arrest; most often due to arrhythmia; most victims have underlying heart diseasestroke – impeded blood supply to some part of the brain, resulting in destruction of brain cells; also referred to as a cerebrovascular accidentischemic stroke – caused by obstruction of a blood vessel by a clothemorrhagic stroke – caused by rupture of a blood vesselthrombus – blood clot in a blood vessel that remains at location of formationformation of deep vein thrombosis:žhttp://www.youtube.com/watch?v=eK5MeJuUQbsembolus – blood clot that breaks away from place of origin and travels through the bloodstreamaneurysm – a sac, or blood-filled pocket, that bulges out of the artery wall due to weakness in the wall of the vesseltransient ischemic attack (TIA) – a small stroke; a temporary interruption of blood supply to the brain, causing numbness or difficulty with speechatherosclerosis – a form of CVD in which the inner layers of artery walls are made thick and irregular by plaque deposits; arteries become clogged and narrow, reducing blood supplyheart surgery for atherosclerosis:http://www.youtube.com/watch?v=SGjHjdEY0vAPATH OF BLOOD FLOW:venae cavae (deoxygenated blood returning to heart from body)right atriumright ventriclepulmonary arteryto the lungspulmonary veinsleft atriumleft ventricleaorta (oxygenated blood leaves heart to rest of body)CARDIOVASCULAR DISEASE (CVD)leading cause of death in the U.S.stroke is 4thaffects more than 81 million Americansclaims one life every 38 sec, nearly 2300 Americans every dayhigh rate of CVD is primarily caused by people’s lifestyleRISK FACTORSMajor risk factors that CAN be changedtobacco use (#1 preventable cause of CVD)high BP/hypertensionunhealthy blood cholesterol levels (hyperlipidemia)physical inactivity/sedentary lifestylehigh BMI, obesitydiabetesTOBACCO USEsmoking increases risk and severity of heart attacka pack a day  2X the risk2+ packs a day  3X the riskheart attack victims who smoke  2-3X more likely to diedoubles the risk of strokeharmful effects of smoking on the CV systemdamages the lining of arterieslowers HDL, raises LDL and triglyceridesnicotine increases BP and HRCO displaces O2causes platelets to become sticky, leading to clottingspeeds the development of fatty deposits in the arteriescan also affect those exposed to 2nd hand smokeenvironmental tobacco smoke (ETS) exposure increases the risk of developing heart disease up to 30%46000 nonsmokers die from heart disease each year as a result of exposure to ETSHIGH BLOOD PRESSUREboth a risk factor for many forms of CVD, and is itself considered the most prevalent form of CVDshort periods of high BP is normal, but chronically high BP is a health riskhypertension = too much pressure against arterial wallsprimary (essential) hypertension – 90% of the cases, cause is unknown; due to a mixture of factorssecondary hypertension – remaining 10%, caused by an underlying illnesscauses:increased output of blood by the heartincreased resistance to blood flow in the arteriesconstriction of smooth muscleatherosclerosisprevalence:33% of Americans have high BP22% of them aren’t aware of their conditionAfrican Am. have highest rate of hypertension (41%)often more severe, more resistant to treatment, more likely to be fatal at an early age*category goes by the higher of the two #sHIGH CHOLESTEROLcholesterol – fatty, wax-like substance that circulates through the bloodstreamimportant component of cell membranes, hormones, fluid that coats the lungs, protective sheaths around nerves, etcexcessive cholesterol  clogs the arteries  increased risk of CVDgood vs. badLDL = bad; shuttles cholesterol from the liver to the organs and tissues; excess accumulates in the blood vesselsHDL = good; shuttles unused, excess cholesterol back to the liver for recyclingPHYSICAL INACTIVITY40-60 million Americans are so sedentary that they are at high risk for developing CVDexercise = magic bullet against heart diseasedecreases BP and resting HRincreases HDL levelsmaintains desirable weightimproves the condition of blood vesselsprevents or controls diabetesdecreases platelet aggregation**A minimum of 30 min a day of moderate physical activity is recommended; for those attempting to manage weight, prevent weight