Granulomatous 'foreign body reactions' contribute to exaggerated in-stent restenosis.

Abstract

BACKGROUND:

Results of previous studies with stents coated with 'biocompatible' polymers showed that severe inflammatory reaction and subsequent in-stent restenosis may occur.

OBJECTIVE:

To evaluate the contribution of granulomatous reaction from uncoated stents to formation of in-stent neointimal hyperplasia.

METHODS:

Uncoated stainless-steel stents were implanted into 21 porcine coronary arteries without oversizing and harvested after 2 months (n = 6) or 6 months (n = 7). We compared the stents with granulomatous reaction with those without foreign-body reaction.

RESULTS:

Granulomatous reactions occurred in five 21 stents and resulted in there being significantly greater in-stent neointimal hyperplasia than there was with stents without foreign-body reaction (angiographic diameter stenosis 45 +/- 36 versus 16 +/- 16%, area of neointimal 3.30 +/- 1.4 versus 1.22 +/- 0.4 mm2, thickness of neointima 0.46 +/- 0.29 versus 0.11 +/- 0.09 mm, stenosed area 56 +/- 24 versus 20 +/- 7%, P < 0.01 for each comparison). This increase in amount of neointima was accompanied by significantly greater proliferating cell nuclear antibody staining (15 +/- 5 versus 3 +/- 2%, P < 0.05) in the presence of a granuloma near the stent struts.

CONCLUSIONS:

A localized granulomatous reaction is associated with a significant increase in amount of stent neointima and proliferation of cells. Thus, permanent stent implants may provoke granulomatous vascular reactions that may affect late-healing responses and clinical outcomes.

• Authors: R Kornowski, M K Hong, R Virmani, R Jones, Y Vodovotz, M B Leon
• Journal: Coronary artery disease (Coron Artery Dis) Vol. 10 Issue 1 Pg. 9-14 ( 1999) ISSN: 0954-6928 [Print] England
• PMID: 10196682 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Proliferating Cell Nuclear Antigen
• Stainless Steel

Topics

• Animals
• Coronary Disease (pathology, therapy)
• Coronary Vessels (pathology)
• Granuloma, Foreign-Body (pathology)
• Hyperplasia
• Proliferating Cell Nuclear Antigen (analysis)
• Recurrence
• Stainless Steel
• Stents
• Swine
• Tunica Intima (pathology)