neointimal hyperplasia
Abnormal proliferation of smooth muscle cells within the arterial intima, typically occurring after vascular interventions.
Full Definition
Neointimal hyperplasia represents an exaggerated healing response following arterial injury, characterized by smooth muscle cell migration from the media to the intima, proliferation, and extracellular matrix deposition. This process is a major cause of restenosis following angioplasty, stenting, and bypass grafting. The response is triggered by endothelial damage and involves inflammatory mediators, growth factors, and mechanical factors. Drug-eluting stents and antiproliferative medications have been developed to inhibit this process and improve long-term patency.
Usage
Usage note: Distinguish from intimal hyperplasia, which is a more general term.
In Context
- "Neointimal hyperplasia was identified as the cause of in-stent restenosis on follow-up angiography." — Catheterization report
- "Drug-eluting stents reduce neointimal hyperplasia compared to bare metal stents." — Device selection rationale