Explanation of Hypertension – HBUO

Explanation of Hypertension – HBUO

October 31, 2019 0 By Jose Scott


(Heart beating) Blood pressure is equal to the cardiac output
—the volume of blood pumped out of the
heart per minute—multiplied by the arterial resistance. (Heart beating) Blood flow depends on the rate of heart
beats and the volume of blood pumped out
with each beat. If rate or volume increases, blood pressure goes up. Likewise, increased resistance raises blood
pressure as when arteries downstream from
the heart constrict. Over time, high blood pressure, or
hypertension, damages many organs. First, the heart works harder to pump out
more blood or against higher resistance. The heart, then, requires more oxygen and
is more susceptible to angina, or a heart
attack. Second, arteries or arterials can be
damaged. Arterial sclerosis results when
blood moves through the vessels at high pressure, damaging the protective cells
lining the vessel. White blood cells are drawn to the damaged
area and form plaque. Third, kidneys can be damaged. The capillaries of the kidney are delicate. Continually subjected to high blood pressure
they break down, becoming permeable to
proteins and other molecules. The kidneys’ tubules can become clogged,
decreasing the kidneys’ ability to make urine. Also, the proteins injure the capillaries’
membranes, causing more damage and
worsening the situation. Fourth, the retina of the eye can be injured if
its delicate capillaries are damaged. Localized hemorrhages can occur, causing
scarring and formation of new, more fragile
capillaries to replace the old ones. Finally, the blood vessels of the brain can be
injured. High blood pressure can clots to
break off from atherosclerotic plaques blocking blood flow to the rest of the brain. This is called a thrombotic stroke. Continual exposure to high blood pressure
may also cause a blood vessel to burst,
leading to a hemorrhagic stroke.