10.8 Circulatory System Disorders Flashcards
What is atherosclerosis?
an accumulation of soft masses of fatty materials, particularly cholesterol, beneath the inner linings of arteries
this is called plaque
What does plaque tend to do?
protrude into the lumen of the vessel and interfere with the flow of blood
When does atherosclerosis begin in most instances?
begins in early adulthood and develops progressively through middle age, but symptoms may not appear until an individual is 50 years or older
What can plaque cause platelets to do?
adhere to the irregular arterial wall, forming a clot
clot remains stationary: THROMBUS
clot dislodges and moves along with the blood: EMBOLUS
What is thromboembolism?
a clot that has been carried in the bloodstream but is now lodged in a blood vessel
MUST BE TREATED OR SERIOUS COMPLICATIONS CAN ARISE
What is hypertension?
high blood pressure
What is considered abnormally high blood pressure under the age of 45? In older people?
under 45: 130/90 mm Hg
older: 140/95 mm Hg
Why is hypertension sometimes called “the silent killer”?
it may not be detected until a stroke or heart attack occurs
When does hypertension most often occur?
secondary to a narrowing of a person’s arteries from atherosclerosis
What does forcing blood through narrowed arteries over time create?
additional pressure on the circulatory system that can damage the blood vessels, heart, and other organs
What medications are used to treat hypertension?
diuretics, vasodilators, and various drugs that improve heart function
What do diuretics do?
reduce the blood volume by increasing urine output
What do vasodilators do?
dilate the blood vessels
How does heart valve disease occur?
- heart valves can be malformed at birth
- more commonly, they degenerate due to age or infections to the point where they no longer prevent the backflow of blood
What is the most common infection that leads to heart valve disease?
a narrowing (stenosis) of the aortic valve opening is the most common, followed by mitral valve prolapse
What is mitral valve prolapse?
abnormally thickened “leaflets” of the mitral valve protrude back into the left ventricle