Intimal thickening during injury is not completely reversible; recurrent injury can lead to which change?

• A. Thrombosis
• B. Aneurysm
• C. Hemorrhage
• D. Stenosis

Answer: (D)

Intimal thickening after injury represents an ongoing remodeling response in which endothelial damage triggers smooth muscle cells to migrate into the intima and proliferate, depositing extracellular matrix. This increases the thickness of the intima and narrows the vessel lumen. If injury happens repeatedly, the thickening accumulates, leading to progressive luminal narrowing—stenosis. This mechanism explains why recurrent injury leads to stenosis rather than acute clotting, dilation, or bleeding.

Thrombosis involves a clot forming in the lumen, which is an acute event. An aneurysm is a dilation or ballooning of the vessel wall due to weakening. Hemorrhage refers to bleeding. The process described—repeated intimal hyperplasia causing tightening of the channel—best fits stenosis.