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A Handbook of Biology

Notes

DÏSØRDËRS ØF ÇÏRÇÜLÅTØRÝ SÝSTËM

Hypertension (High Blood

Pressure) Here, the blood

pressure is higher than normal

systolic (pumping) pressure

(120 mm Hg) and normal

diastolic (resting) pressure

(80mm Hg), i.e. above 120/80mm

Hg. If the BP is 140/90 mm Hg or

above, it is hypertension. It leads

to heart diseases and affects

vital organs (brain, kidney, etc.)

Coronary Artery Disease (CAD)

or Atherosclerosis: Here,

calcium, fat, cholesterol and

fibrous tissue are deposited in

coronary arteries. It makes the

lumen of arteries narrower and

thereby affects the blood supply.

Angina (Angina Pectoris): An

acute chest pain. It occurs due

to improper blood flow to the

heart muscle. It is common

among middle-aged and elderly

people.

Heart Failure (Congestive Heart

Failure): It is the condition in which

heart is not pumping blood

enough to meet the needs of the

body. Congestion of the lungs is

the main symptom. Heart failure is

not same as cardiac attack (heart

stops beating) or a heart attack.

Myocardial infarction, sudden

damage of heart muscle due to

inadequate blood supply.