
As the blood passes through this blockage, what happens to the blood pressure?
Arteriosclerotic plaques forming on the inner walls of arteries can decrease the effective crosssectional area of an artery. Even small changes in the effective area of an artery can lead to very large changes in the blood pressure in the artery and possibly to the collapse of the blood vessel.
Imagine a healthy artery, with blood flow velocity of v_0 = 0.14 m/s and mass per unit volume of
P=1050 kg/m^3. This leads to a value for the kinetic energy per unit volume of blood of
2
1/2 pv0 =1/2(1050kg/m^3)(0.14km/s)^2
10Pa.
Imagine that plaque has narrowed an artery to onefifth of its normal crosssectional area (an 80% blockage).
Compared to normal blood flow velocity, v_0, the velocity of blood as it passes through this blockage by 5 v_0.
By factor of 25 the kinetic energy per unit of blood volume change as the blood passes through this blockage.
As the blood passes through this blockage, what happens to the blood pressure?
Does it increase? If so by how much 240Pa? or 40Pa?
Decrease? If so by 240 Pa? or 40 Pa?
Stay the same?
If you a medical profession can you tell me if it increases / decrease/ or stays the same if you don't understand the math?
