Fibrinogen and high-sensitive C-reactive protein as serologic predictors for perioperative cerebral microembolic lesions after carotid endarterectomy

Biomarkers in unstable carotid plaque: Physiopathology and Prediction

AIMS

To study the role of cytokines and vascular inflammatory biomarkers in unstable carotid plaque.

BACKGROUND

Clinical studies showed that not only the degree of stenosis but also the type of carotid plaque can be responsible for ipsilateral ischemic stroke.

OBJECTIVE

The objective of this study is to suggest a role for vulnerable carotid atherosclerotic disease in the occurrence of ischemic stroke.

METHODS

PubMed, Embase, Cochrane library, and reference lists have been used to evaluate articles published until February 15, 2021.

RESULTS

Several factors may be involved in unstable plaque. Clinical studies support the involvement of brain inflammatory biomarkers as well as cytokines in the unstable carotid plaque.

CONCLUSIONS

Biomarkers could help to stratify patients with a vulnerable carotid plaque and to personalize the drug treatment. In this review, we briefly discuss the characteristics of vulnerable plaque and the role of biomarkers in the vulnerable carotid plaque.

Ultrasound-Based Carotid Plaque Characteristics Help Predict New Cerebral Ischemic Lesions after Endarterectomy

The aim of this study was to identify the ultrasound-based carotid plaque characteristics associated with new cerebral ischemic lesions after carotid endarterectomy (CEA). Between January 2013 and December 2018, carotid duplex ultrasound was performed in 1061 patients who underwent CEA. Brain magnetic resonance diffusion-weighted imaging (DWI) was performed pre-operatively and within 30 d after CEA. New cerebral ischemic lesions on DWI were observed in 169 patients. The cutoff value gray-scale median (GSM) used to distinguish DWI-positive from DWI-negative patients was 30.5, with an area under the receiver operating characteristic curve of 0.837. A larger proportion of multiple DWI lesions were observed in the GSM ≤30.5 group (59.5% vs. 41.5%, p = 0.030). Univariate and multivariate analyses identified GSM ≤30.5, ulcerated carotid plaques and pre-operative ischemic symptoms as predictors of post-operative cerebral DWI lesions. Our results indicate that ultrasound-based carotid plaque characteristics help predict new cerebral ischemic lesions after CEA.

Inflammation of carotid plaques and risk of cerebrovascular events

Carotid atherosclerotic plaques represent a risk for ischemic stroke. The data indicate that the risk for distal embolization from atherosclerotic lesions in internal carotid arteries is not related only to the degree of stenosis but also to the composition of plaques. The stability of atherosclerotic plaque depends on the thickness of the fibrous cap and plaque hemorrhage. Recent research indicated that the inflammatory activity of atherosclerotic lesions is pivotal in the progression of atherosclerotic plaques. It also promotes the development of unstable atherosclerotic lesions and is related to thromboembolic cerebrovascular complications. Inflammation destabilizes atherosclerotic plaques through the degradation of their fibrotic structure. Inflammation of atherosclerotic plaques was confirmed by histopathologic findings and levels of circulating inflammatory markers which were correlated to the intensity of the inflammation in atherosclerotic lesions. Recently, new techniques like fluorodeoxyglucose positron emission tomography (18-FDG PET) were developed for the identification of inflammation of atherosclerotic lesions in the vessel wall in vivo. Systemic inflammatory markers, particularly interleukins, tumor necrosis factor-alpha and metalloproteinases were shown to be related to the intensity of the inflammatory process in atherosclerotic lesions and the cerebrovascular events. Identification of inflamed atherosclerotic plaques may help to identify unstable atherosclerotic lesions and subjects at high risk for cerebrovascular incidents who need intensive preventive measures including anti-inflammatory medication.

BARI 2D: A Reanalysis Focusing on Cardiovascular Events

OBJECTIVE

To reanalyze the Bypass Angioplasty Revascularization Investigation 2 Diabetes trial using a new composite cardiovascular disease (CVD) outcome to determine how best to treat patients with type 2 diabetes mellitus and stable coronary artery disease.

PATIENTS AND METHODS

From January 1, 2001, to November 30, 2008, 2368 patients with type 2 diabetes mellitus and angiographically proven coronary artery disease were randomly assigned to insulin-sensitizing (IS) or insulin-providing (IP) therapy and simultaneously to coronary revascularization (REV) or no or delayed REV (intensive medical therapy [MED]), with all patients receiving intensive medical treatment. The outcome of this analysis was a composite of 8 CVD events.

RESULTS

Four-year Kaplan-Meier rates for the composite CVD outcome were 35.8% (95% CI, 33.1%-38.5%) with IS therapy and 41.6% (95% CI, 38.7%-44.5%) with IP therapy (P=.004). Much of this difference was associated with lower in-trial levels of fibrinogen, C-reactive protein, and hemoglobin A_1c with IS therapy. Four-year composite CVD rates were 32.7% (95% CI, 30.0%-35.4%) with REV and 44.7% (95% CI, 41.8%-47.6%) with MED (P<.001). A beneficial effect of IS vs IP therapy was present with REV (27.7%; 95% CI, 24.0%-31.4% vs 37.5%; 95% CI, 33.6%-41.4%; P<.001), but not with MED (43.6%; 95% CI, 39.5%-47.7% vs 45.7%; 95% CI, 41.6%-49.8%; P=.37) (homogeneity, P=.05). This interaction between IS therapy and REV was limited to participants preselected for coronary artery bypass grafting (CABG). The lowest composite CVD rates occurred in patients preselected for CABG and assigned to IS therapy and REV (17.3%; 95% CI, 11.8%-22.8%).

CONCLUSION

In the Bypass Angioplasty Revascularization Investigation 2 Diabetes trial, the IS treatment strategy and the REV treatment strategy each reduces cardiovascular events. The combination of IS drugs and CABG results in the lowest risk of subsequent CVD events.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00006305.

Silent brain infarcts on diffusion-weighted imaging after carotid revascularisation: A surrogate outcome measure for procedural stroke? A systematic review and meta-analysis

Aim

To investigate whether lesions on diffusion-weighted imaging (DWI+) after carotid artery stenting (CAS) or endarterectomy (CEA) might provide a surrogate outcome measure for procedural stroke.

Materials and Methods

Systematic MedLine® database search with selection of all studies published up to the end of 2016 in which DWI scans were obtained before and within seven days after CAS or CEA. The correlation between the underlying log odds of stroke and of DWI+ across all treatment groups (i.e. CAS or CEA groups) from included studies was estimated using a bivariate random effects logistic regression model. Relative risks of DWI+ and stroke in studies comparing CAS vs. CEA were estimated using fixed-effect Mantel-Haenszel models.

Results

We included data of 4871 CAS and 2099 CEA procedures (85 studies). Across all treatment groups (CAS and CEA), the log odds for DWI+ was significantly associated with the log odds for clinically manifest stroke (correlation coefficient 0.61 (95% CI 0.27 to 0.87), p = 0.0012). Across all carotid artery stenting groups, the correlation coefficient was 0.19 (p = 0.074). There were too few CEA groups to reliably estimate a correlation coefficient in this subset alone. In 19 studies comparing CAS vs. CEA, the relative risks (95% confidence intervals) of DWI+ and stroke were 3.83 (3.17-4.63, p < 0.00001) and 2.38 (1.44-3.94, p = 0.0007), respectively.

Discussion

This systematic meta-analysis demonstrates a correlation between the occurrence of silent brain infarcts on diffusion-weighted imaging and the risk of clinically manifest stroke in carotid revascularisation procedures.

Conclusion

Our findings strengthen the evidence base for the use of DWI as a surrogate outcome measure for procedural stroke in carotid revascularisation procedures. Further randomised studies comparing treatment effects on DWI lesions and clinical stroke are needed to fully establish surrogacy.

Hidrocortisona reduz as concentrações séricas dos biomarcadores inflamatórios séricos em pacientes submetidos a endarterectomia de carótida

ResumoContextoA hidrocortisona pode reduzir a concentração dos biomarcadores inflamatórios séricos e teciduais.ObjetivoAnalisar a atividade inflamatória da proteína C-reativa ultrassensível (PCR-US), do fator de necrose tumoral (FNT)-alfa e do fator de crescimento do endotélio vascular (FCEV) séricos e teciduais, mediante administração intraoperatória de hidrocortisona, após endarterectomia de artéria carótida (EAC).MétodoVinte e dois pacientes foram divididos em Grupo Controle (5 assintomáticos e 6 sintomáticos) – não foi administrada hidrocortisona – e Grupo 1 (4 assintomáticos e 7 sintomáticos) – foram administrados 500 mg intravenoso de hidrocortisona. O PCR-US, o FNT-alfa e o FCEV séricos foram dosados no pré-operatório e em 1 hora, 6 horas e 24 horas após a EAC. Na placa carotídea, mensuramos os níveis de FNT-alfa e FCEV.ResultadosO grupo 1 exibiu menor concentração sérica de FNT-alfa em 1 hora (p=0,031), 6 horas (p=0,015) e 24 horas (p=0,017) após a EAC, e menor concentração de FCEV em 1 hora (p=0,006) e 6 horas (p=0,005) após a EAC, em relação ao grupo controle. Os pacientes sintomáticos do grupo 1 exibiram menor concentração de FNT-alfa em 1 hora e 6 horas após a EAC, e menor concentração de FCEV em 1 hora após a EAC, em relação ao grupo controle. Não houve diferença estatística entre as concentrações teciduais de FNT-alfa e FCEV entre o grupo controle e o grupo 1.ConclusãoA hidrocortisona reduz as concentrações séricas pós-operatórias de FNT-alfa e FCEV, em especial nos sintomáticos; porém, não reduz os níveis teciduais destes biomarcadores.

Current role of biomarkers in carotid disease: a systematic review

BACKGROUND AND PURPOSE

Accumulating evidence suggests that carotid plaque vulnerability can be used as a determinant of ischemic stroke risk stratification and carotid intervention. Novel markers of high-risk carotid plaque in patients are needed.

SUMMARY OF REVIEW

Advances in cellular and molecular pathophysiology, the demand for accurately predicting carotid risk, and choosing the optimal prevention strategy are stimulating great interest in the development of novel surrogate markers. Biomarkers in cardiovascular disease are expected to predict the natural history, clinical outcomes, and the efficacy of disease-modifying interventions. We aimed to review the literature regarding clinical data on novel serum biomarkers related to ischemic cerebrovascular events associated with carotid artery disease. We provide background information on the biomarkers related to all aspects of carotid disease: natural history, carotid intervention strategies for symptomatic and asymptomatic patients, perioperative risk prediction, and their therapeutic implications.

CONCLUSION

At present, heterogeneous data support evidence that biological markers can help existing practices to more accurately assess patients at risk for stroke. Randomized-controlled trials for carotid artery disease and carotid intervention, incorporating biomarkers, are needed.

Patient-related risk factors for postoperative adverse events

PURPOSE OF REVIEW

The risk of adverse outcome in patients undergoing major surgery is affected both by cardiorespiratory fitness, and the presence and severity of comorbidities. Accurate risk stratification is essential for the identification of patients who may benefit from specific perioperative management strategies or from an augmented level of perioperative care. Risk stratification techniques include risk prediction models, assessment of functional capacity and novel biochemical markers. This review examines the evidence for the use of these different techniques in perioperative patients.

RECENT FINDINGS

There remains considerable variation in the predictive ability of risk stratification models, in part due to the subjective nature of some of the component variables. Whereas a basic assessment of functional capacity using structured questionnaires may be helpful, in patients thought to be at high risk, the most accurate technique may be cardiopulmonary exercise testing, although the strength of the hypothesized relationship between functional capacity and perioperative outcome has not been fully defined. There have been advances in the identification and refinement of biochemical markers for risk prediction, in particular, brain natriuretic peptide and C-reactive protein. Currently, few centres routinely systematically utilize these strategies to risk stratify perioperative patients.

SUMMARY

The development of improved risk stratification techniques would be assisted by large-scale epidemiological studies. Improvements to currently used risk prediction models are likely to result from the use of variables which more objectively measure patient health and fitness than current tools, and may use a combination of all the above techniques to improve predictive accuracy.

Evaluation of serum matrix metalloproteinases as biomarkers for detection of neurological symptoms in carotid artery disease

OBJECTIVE

Relevant soluble matrix metalloproteinases (MMPs), their inhibitors, tissue inhibitor of metalloproteinases (TIMPs), and serological factors were analyzed as possible biomarkers for neurological symptoms in patients with carotid artery stenosis.

METHODS AND RESULTS

Asymptomatic (n = 76) and symptomatic (n = 69) patients were evaluated. Serum levels of collagenases (MMP-1, -8), gelatinases (MMP-2, -9), stromelysin (MMP-3), matrilysin (MMP-7), and TIMP-1, -2 were determined by enzyme-linked immunosorbant assay (ELISA). Furthermore, fibrinogen, C-reactive protein (CRP), leukocytes, and further serological parameters were measured. Circulating MMP-7, -8, -9, and TIMP-1 were significantly enhanced in symptomatic individuals with P < .001 for MMP-7 and P < .05 for MMP-8, -9, and TIMP-1. Significant correlations were found between various MMPs with highest correlation coefficient of r = .749 between MMP-8 and -9. In addition, MMP-1, -3, -7, -9 correlated significantly with leukocytes, MMP-1, and TIMP-1 with thrombocytes, MMP-8 with fibrinogen, and MMP-7 with creatinine. Combination of more than one biomarker led to significantly enhanced positive predictive value (PPV) for neurological symptom compared to single MMP (MMP-7 + MMP-9: PPV = 73.1%, MMP-7 + MMP-8 + MMP-9: PPV = 73.8% vs. PPV = 62.5%; P < .001).

CONCLUSIONS

Thus, using appropriate analytical approaches, we showed for the first time the possibility to use set of relevant biomarkers as predictors of neurological symptoms. Such biomarkers together with current diagnostic techniques may further contribute to recognize vulnerable lesions to define patients at risk.

C-reactive protein (CRP): more than just an innocent bystander?

This editorial discusses whether measuring C-reactive protein (CRP) levels can be used as a predictor of vascular risk. The agents that reduce CRP levels and the evidence for a possible causative role of CRP in the pathogenesis of coronary events and atherosclerosis are also considered. There is a need to further elucidate the role of CRP, as well as the clinical relevance, if any, of CRP-lowering agents.