Atherosclerotic plaque composition and occurrence of restenosis after carotid endarterectomy.
BACKGROUND
Previous studies have assessed the predictive value of clinical and angiographic parameters for development of restenosis after vascular interventions. The composition of the atherosclerotic plaque at the intervention site has had limited evaluated as a marker for restenosis [corrected].


OBJECTIVE
To investigate the relationship between atherosclerotic plaque histology and the occurrence of restenosis after carotid endarterectomy.


METHODS
The Athero-Express study is a longitudinal vascular biobank study that includes the collection of atherosclerotic plaques of patients undergoing primary carotid endarterectomy. Five hundred patients were prospectively followed up between April 1, 2002, and March 14, 2006, to assess carotid artery restenosis measured by duplex ultrasound 1 year after the intervention.


METHODS
Risk of carotid restenosis in relation to predefined histological characteristics (macrophage and smooth muscle cell infiltration, collagen, calcifications, intraplaque bleeding, luminal thrombus, and lipid core size), adjusted for clinical characteristics (multivariate logistic regression analysis).


RESULTS
At 1 year, 85 patients (17%) developed 50% or greater restenosis, including 40 patients (8%) who developed 70% or greater restenosis of the target vessel. Patients whose histological examination of the plaque revealed marked macrophage infiltration (n = 286) had a lower risk than those with none or minor macrophage infiltration (n = 214) of developing 50% or greater restenosis (risk difference, 11.5% vs 24.3%; adjusted odds ratio [OR], 0.43; 95% confidence interval [CI], 0.26-0.72) and a lower risk of developing 70% or greater restenosis (risk difference, 4.5% vs 12.6%; adjusted OR, 0.36; 95% CI, 0.17-0.74). Patients (n = 177) with a plaque having a large lipid core size (>40%) had a lower risk than those (n = 94) with a plaque having a lipid core size of less than 10% of developing 50% or greater restenosis (risk difference, 11.3% vs 25.5%; adjusted OR, 0.40; 95% CI, 0.19-0.81) and a lower risk of developing 70% or greater restenosis (risk difference, 5.6% vs 14.9%; adjusted OR, 0.42; 95% CI, 0.17-1.04), independent of clinical characteristics.


CONCLUSIONS
Plaque composition is an independent predictor of restenosis after carotid endarterectomy. The dissection of a lipid-rich, inflammatory plaque is associated with reduced risk of restenosis.
Hellings
Willem E
WE
Department of Vascular Surgery, University Medical Center, Utrecht, The Netherlands.
Moll
Frans L
FL
De Vries
Jean-Paul P M
JP
Ackerstaff
Rob G A
RG
Seldenrijk
Kees A
KA
Met
Rosemarie
R
Velema
Evelyn
E
Derksen
Wouter J M
WJ
De Kleijn
Dominique P V
DP
Pasterkamp
Gerard
G
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016893:Carotid Stenosis / Q000473:pathology* / Q000503:physiopathology / Q000601:surgery*; D016894:Endarterectomy, Carotid; D005260:Female; D006801:Humans; D050356:Lipid Metabolism; D008137:Longitudinal Studies; D008264:Macrophages; D008297:Male; D008875:Middle Aged; D010587:Phagocytosis; D012008:Recurrence