Distal to a stenosis, flow becomes _____.

Distal to a stenosis, flow becomes _____.

• A. Turbulent
• B. Laminar
• C. Parabolic flow profile
• D. Stenotic flow profile

Answer: (A)

Distal to a stenosis, flow becomes turbulent because the narrowing forces the blood to accelerate, and when that high-velocity jet exits into the wider vessel, it destabilizes and forms eddies and chaotic vortices downstream. This transition raises local inertial effects and disrupts the smooth layering of blood, so the flow is no longer laminar. Laminar flow would be smooth and orderly with a paraboloid velocity profile in a uniform tube, which isn’t the case after a stenosis. The notion of a “stenotic flow profile” isn’t the standard way to describe the downstream state; the key idea is that the flow becomes turbulent downstream of the constriction.

Distal to a stenosis, flow becomes turbulent because the narrowing forces the blood to accelerate, and when that high-velocity jet exits into the wider vessel, it destabilizes and forms eddies and chaotic vortices downstream. This transition raises local inertial effects and disrupts the smooth layering of blood, so the flow is no longer laminar. Laminar flow would be smooth and orderly with a paraboloid velocity profile in a uniform tube, which isn’t the case after a stenosis. The notion of a “stenotic flow profile” isn’t the standard way to describe the downstream state; the key idea is that the flow becomes turbulent downstream of the constriction.