A lipid-poor plaque and asymptomatic status in women are associated with higher peak systolic velocity on duplex ultrasound after carotid endarterectomy

A systemic review into carotid plaque features as predictors of restenosis after carotid endarterectomy

OBJECTIVE

Restenosis after carotid endarterectomy (CEA) limits its long-term efficacy for stroke prevention. Thus, it is of utmost importance to identify the factors that predispose a patient to restenosis after CEA. This systemic review aims to survey the current literature regarding restenosis after CEA and discuss the predictive value of carotid plaque features.

METHODS

A systemic review of studies on the predictive value of carotid plaque features for restenosis after CEA was conducted according to the PRISMA guidelines. PubMed/MEDLINE and Embase databases were searched up to March 20, 2020. Two authors independently extracted the data and assessed the risk of bias with the Quality in Prognosis Studies tool. Given the heterogeneity in the measurement of prognostic factors, types of CEA, and clinical outcomes, a qualitative synthesis was performed.

RESULTS

Twenty-one articles with a sample size that ranged from 11 to 1203 were included in this systematic review. Based on the presence of calcification in original carotid plaques, two progression patterns of restenosis were hypothesized: patients with calcified plaques may experience a temporary increase in the intima-media thickness (IMT) followed by a decrease in IMT after CEA, whereas patients with noncalcified plaques may experience a gradual increase in IMT after CEA. Accordingly, patients with a high calcium score may have a high restenosis rate within 6 months after CEA and a low restenosis rate thereafter. Thus, the late restenosis rate in patients with uniformly echogenic plaques was lower than that in patients with uniformly echolucent plaques. Pathologically, a lipid-rich, inflammatory carotid plaque is associated with a decreased risk of restenosis within 1 year after CEA, mainly owing to the relatively mild reactive intimal hyperplasia at the surgical site and active inflammation in the remaining media and adventitia. Molecular predictors for restenosis included a Mannose-binding lectin 2 genotype, preoperative C-reactive protein, serum homocysteine, apolipoprotein J, vitamin C, and telomere length of carotid plaques.

CONCLUSIONS

This review demonstrated that carotid plaque features, including imaging features, cellular composition, and molecular features, are correlated with the risk of restenosis after CEA. A comprehensive evaluation of plaque characteristics may help to stratify the risk of restenosis after CEA.

Echolucent carotid plaque is associated with restenosis after carotid endarterectomy

OBJECTIVE

The mechanism of carotid endarterectomy (CEA) restenosis remains unclear. Our research aimed to investigate the relationship between the carotid plaque grayscale median (GSM) value and restenosis after CEA.

METHODS

Between January 2010 and January 2018, 1280 consecutive patients underwent CEA at our institution; 32 patients were diagnosed with restenosis by ultrasound at 1 year after CEA. The correlations between plaque GSM, plaque echogenicity, clinical manifestations, shunting, and restenosis were analyzed.

RESULTS

In total, 829 patients were ultimately enrolled; 32 (4%) presented diagnoses of restenosis (mean age 67.3 ± 8.0 years, 81.2% men). The GSM value was lower in the restenosis group (68.1 ± 19.9 vs 59.9 ± 14.7, p = 0.02). After multiple logistic regression analysis, the GSM value was found to be an independent risk factor for restenosis (OR 0.976, 95% CI 0.957-0.995). Shunting was another significant independent risk factor for restenosis (OR 2.39, 95% CI 1.07-5.34). The GSM cutoff value for predicting restenosis was 75 (sensitivity 0.38, specificity 0.84, area under the curve 0.62). We separated the patients into 2 groups by GSM (GSM ≤ 75 and GSM > 75 subgroups). Comparison of the 2 groups indicated that symptomatic manifestation was related to restenosis in the subgroup with GSM ≤ 75, indicating predominantly echolucent plaques, but not in the subgroup with GSM > 75, indicating predominantly echogenic plaques.

CONCLUSIONS

Predominantly echolucent carotid plaques, as measured by GSM, had a higher restenosis risk at 1 year than echogenic plaques.

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.

Preeclampsia and coronary plaque erosion: Manifestations of endothelial dysfunction resulting in cardiovascular events in women

Atherosclerosis is the major underlying pathology of cardiovascular disease (CVD). The risk for CVD is increased in women with a history of preeclampsia. Multiple studies have indicated that accelerated atherosclerosis underlies this increased CVD risk. Furthermore, it has been suggested that endothelial dysfunction and inflammation play an important role in the increased CVD risk of women with preeclampsia. Rupture or erosion of atherosclerotic plaques can induce the formation of thrombi that underlie the onset of acute clinical CVD such as myocardial infarction and stroke. In relatively young women, cardiovascular events are mainly due to plaque erosions. Eroded plaques have a distinct morphology compared to ruptured plaques, but have been understudied as a substrate for CVD. The currently available evidence points towards lesions with features of stability such as high collagen content and smooth muscle cells and with distinct mechanisms that further promote the pro-thrombotic environment such as Toll Like Receptor (TLR) signaling and endothelial apoptosis. These suggested mechanisms, that point to endothelial dysfunction and intimal thickening, may also play a role in preeclampsia. Pregnancy is considered a stress test for the cardiovascular system with preeclampsia as an additional pathological substrate for earlier manifestation of vascular disease. This review provides a summary of the possible common mechanisms involved in preeclampsia and accelerated atherosclerosis in young females and highlights plaque erosion as a likely substrate for CVD events in women with a history of preeclampsia.

Clinical Risk Factors and Plaque Characteristics Associated with New Development of Contralateral Stenosis in Patients Undergoing Carotid Endarterectomy

BACKGROUND

Following carotid endarterectomy (CEA), cerebrovascular hemodynamic may be hampered by ipsilateral restenosis or development of contralateral stenosis. It remains to be clarified if these patients need follow-up for identifying development of contralateral stenosis. Identification of risk factors contributing to development of contralateral stenosis could allow more specific follow-up. In this current study, we assessed clinical risk factors and plaque characteristics of patients undergoing CEA with development of new contralateral stenosis during mid-term follow-up.

METHODS

Seven hundred and sixty patients undergoing CEA between 2003 and 2011 at UMC Utrecht were included. Atherosclerotic plaques were excised and analyzed for smooth muscle cells (SMCs), collagen, macrophages, lipid core, plaque hemorrhage and vessel density. Patients underwent clinical and duplex ultrasound follow-up at 3 and 12 months and yearly thereafter. Association between plaque- and patient characteristics with development of contralateral stenosis ≥50% was assessed with univariate and multivariate analysis. Clinical outcome during follow-up was associated with development of new contralateral stenosis.

RESULTS

After a median follow-up time of 2.5 years, development of contralateral stenosis was observed in 108 patients (20%). Presence of high collagen (p = 0.025) and high SMC (p = 0.027) was associated with development of new contralateral stenosis, whereas large lipid core was negatively associated with new development of contralateral stenosis (p = 0.034). The same plaque characteristics were related to contralateral occlusion. History of coronary artery disease (p = 0.031) and asymptomatic presentation (p = 0.000) were univariably associated with development of contralateral stenosis. Multiple regression analysis indicated that asymptomatic status was independently associated with contralateral stenosis (p = 0.001). Patients with new development of contralateral stenosis more often showed symptoms during follow-up (p = 0.049).

CONCLUSION

Dissection of a lipid-poor, collagen-rich or SMC-rich plaque yielded an association with development of new contralateral stenosis during mid-term follow-up after CEA. Asymptomatic patients had a significantly higher risk for development of contralateral stenosis. New contralateral stenosis was related to the presence of new cerebral symptoms. These findings may help to develop individual treatment algorithms for patients with cerebrovascular atherosclerotic burden.