Analysis of Recurrent Stenosis After Carotid Endarterectomy Featuring Primary Plaque Calcification

BACKGROUND: The relationship between calcification in primary plaque and restenosis after carotid endarterectomy (CEA) has been seldom investigated. OBJECTIVE: To clarify the relationship between characteristics of calcified carotid plaque and recurrent stenosis after CEA, as well as the disease's natural course. METHODS: Ninety-four plaques out of 107 consecutive CEAs were retrospectively analyzed with regard to calcification, employing calcium score as well as shape, location, and other characteristics of original plaques. CEA was performed in a standard fashion with primary closure using an internal shunt. Restenosis was assessed by direct measurement of stenosis mainly using multidetector row computed tomography (CT) angiography. RESULTS: Univariate analysis revealed that calcium score and calcification circularity score were significantly lower in more than moderate restenosis (≥50%; 422.1 ± 551.6 vs 84.2 ± 92.0, P < .001; 1.8 ± 1.3 vs 1.1 ± 0.3, P < .001, respectively). Receiver operating characteristic analysis demonstrated a calcium score of 80, which was the optimal cutoff value for restenosis over 50% (sensitivity 0.70, specificity 0.68, pseudopositive ratio 0.32, area under curve 0.71, Youden's index 0.38). Low calcium score (OR 2.88, CI 1.06-7.79, P = .04) and low calcification circularity (OR 5.72, CI 1.42-23.1, P = .01) were independent predictors for more than moderate recurrent carotid stenosis 1 year postoperatively. Cases with decreasing tendency of restenosis showed higher calcium scores than those with increasing or unchanged tendency (217.2 ± 245.3 vs 164.5 ± 155.5, P < .001). Lower calcium score cases showed lower restenosis-free survival. CONCLUSION: Carotid plaque calcification may be inversely associated with recurrent stenosis 1 year after CEA or later. Preoperative CT assessment for less calcification will benefit restenosis patients by early prediction and close follow-up.