Chronic rejection in a cardiac allograft manifests histologically as concentric intimal hyperplasia of coronary arteries causing diffuse stenosis. This process differs from atherosclerosis chiefly because it involves:

• A Lipid-laden foam cells within the intima
• B Fibrinous pericarditis with vessel wall necrosis
• C Diffuse circumferential involvement including intramyocardial branches, driven by chronic immune-mediated injury ✓
• D Isolated proximal epicardial plaque rupture

Explanation

Transplant coronary artery disease, the hallmark of chronic rejection, produces smooth muscle proliferation and myointimal thickening diffusely along vessels including distal branches, driven by ongoing alloimmune injury to endothelium. Conventional atherosclerosis is focal, proximal, eccentric and lipid driven with foam cells, sparing small intramyocardial branches. The diffuse pattern explains why angiography underestimates the disease and why retransplantation may be needed.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.