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cardiovascular disease (CVD)
any disease involving the heart and / or blood vessels
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- tobacco use, physical inactivity, and poor diet.
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cardiovascular system
- network of blood vessels (arteries, veins, and capillaries) and a pump ( the heart) that circulate the blood throughout the body
- -heart is fist sized muscle with four chambers : right and left atria: righ and left ventricles: separated from one another by valves.
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right side of the heart is involved in pulmonary circulation
-pumping oxygen poor blood to the lungs and oxygen poor blood to the heart
- left side of the heart is involved in systemic circulation
- -pumping oxygen rich blood to the rest of the body and returning oxygen poor blood to the heart
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Pulmonary circulation
oxygen poor or deoxygenated blood returning from the body to the heart enters the right atrium via large veins called the inferior and superior vena cava.
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after the right atrium fills, it contracts and moves the blood into the right ventricle
the right ventricle fills and contracts, moving blood into the lungs via the right and left pulmonary arteries
- the pulmonary artery branches into a network of smaller arteries and arterioles that eventually become the pulmonary cappilaries
- capillaries are the smallest blood vessels; some capillary walls are only one cell think, readily allowing the exchange of gases and molecules.
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in thw network of capillaries=red blood cells in the blood pick up oxygen and discard carbon dioxide, a waste product from the cells. capillaries then unite and form venules, and venules join to become pulmonary veins.
pulmonary veins return oxygen-rich blood from the lungs to the left atrium of the heart.
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systemic circultaion
- left atrium fills and contracts to move oxygen-ricfh blood into the left ventricle
- the left ventricle fills, contracts, and moves oxygen-rich blood into the body via the aorta
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aorta--- the largest artery in the body. the aorta branches into smaller and smaller arteries, and eventually, oxygen-rich nutrient-rich blood enters the capillaries located throughout the body
at these sites, red blood cells release oxygen and nutrients to the tissues and pick up carbon dioxide to be carried back to the lungs.
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capillaries unite to form veins and eventually connnect to the inferior and superior vena cava
vena cava returns the oxygen-poor blood to the heart..cycle repeats
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sinus node--or sinoatrial (sa) node in the right atrium
- the signal spreads through a defined course leading first to contraction of the right and left atria, then to contraction of the right and left ventricles
- the contraction and relaxation of the ventricles is what we feel and hear as the heartbeat. contraction phases systole and relaxation phases diastole
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leading cause of death in us..36.3 all deaths
1.4 mill americans...for men it is decreasing over past thirty years
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cardiovascular disease
heart attack, stroke, peripheral atery disease, congestive heart failure,
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atherosclerosis
years to develop..young age starts..a thickening or hardening of the arteries due to the buildup of fats, cholesterol, cellular waste products, calcium, and other substances in artery walls
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atherosclerosis starts with damage to the inner lining and the formation of a fatty streak in an atery
fatty streaks consist of an accumulation of lipoproteins--conbo of proteins, phosholipids (fat molecules wiht phosphate groups chemically attached ) and cholesterol (waxy , fatlike substance )..lipo carry choles and fats through the blood stream
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inner lining of artery wall damaged by tobacco smoke, high bp, lesion..
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plaque- accumulation of debris in an artery wall..consisting of lipoproteins, white blood cells, collagen, and other substances
aneurysm- weak or stretched spot in an artery wall that can tear or rupture, causing sudden death
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ischemia
coronary artery be-comes narrowed or blocked, the heart muscle does not get enought oxygen rich blood
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myocardial infarction
lack of blood to the heart muscle death of heart tissue..heart attack..artery is completely blocked
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coronary thrombosis
sudden death..
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angina
pain, pressure, heaviness, tightness in the center of the chest..
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sinus node- 60-100 beats per minute
arrhythmia- irregular or disorganized heartbeat
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ventricular fibrillation
particular arrhythmia ..ventricles contract rapidly and erratically.
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blocked blood flow- stroke, CVA..3rd leading cause of death.
ischemic strokes 87 percent of all strokes and occur when an artery in the brain becomes blocked the same way that a heart attack occurs when a coronary artery is blocked, and prevents the brain from recieving blood flow.
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thrombus
blood clot that develops in a narrowed artery or an embolism ..clot that develops elsewhere often in the heart , travels to the brain, and lodges in an artery
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hemorrhagic strokes
13 percent of strokes and occur when a brain artery reptures, bleeds into the surrounding area, and compresses brain tissue
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2 types of hemorrhagic stroke
tracerebral hemorrhagic--10 percent and occur when the ruptured artery is within brain tissue. subarachnoid hemmorhagic strokes accounts for 3 percent and occur when the ruptured artery is on the brains surface and blood accumulates between the brain and the skull
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hemmorrhagic strokes may be due to a head injusy or a ruptured anerurysm
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