Risk Prediction Tools to Improve Patient Selection for Carotid Endarterectomy Among Patients With Asymptomatic Carotid Stenosis

Systemic immune-inflammation index for predicting poor outcome after carotid endarterectomy: A novel hematological marker

OBJECTIVE

To investigate the predictive role of systemic immune-inflammation index (SII) on postoperative poor outcome in patients undergoing carotid endarterectomy (CEA).

METHODS

A total of 347 patients undergoing elective isolated CEA between March 2010 and April 2022 were included in this multicenter retrospective observational cohort and risk-prediction study and were divided into two groups as poor outcome group (n = 23) and favorable outcome group (n = 324). Poor outcome was defined as the presence of at least one of the complications within 30 days of surgery including stroke, myocardial infarction, and death. The patients' baseline clinical characteristics, comorbidities, and hematological indices were derived from the complete blood count (CBC) analysis, and perioperative data, outcomes, and complications were screened, recorded, and then compared between the groups. Multivariate logistic regression and receiver-operating characteristic (ROC) curve analyses were conducted following univariate analyses to detect the independent predictors of poor outcome as well as the cutoff values with sensitivity and specificity rates.

RESULTS

A total of 23 patients out of 347 (6.6%) manifested poor outcome; and stroke, myocardial infarction, and death occurred in 13, 3, and 7 cases, respectively. There were no significant differences between the groups in terms of basic clinical characteristics, comorbidities, and perioperative data, except for lengths of intensive care unit and hospital stays. Although the median values of PLT, PLR, NLR, and SII of the poor outcome group were found to be significantly higher than the favorable outcome group in univariate analysis, only SII was detected to be a significant and independent predictor of poor outcome in multivariate logistic regression analysis (OR = 1.0008; 95% CI: 1.0004-1.0012; p = 0.002). ROC curve analysis revealed that SII of 1356 × 103/mm3 constituted the cutoff value for predicting poor outcome with 78.3% sensitivity and 64.5% specificity (AUC = 0.746; 95% CI: 0.64-0.851).

CONCLUSIONS

Our study revealed for the first time in the literature that SII significantly predicted poor outcome after CEA.

Cost-Effectiveness of Screening Asymptomatic Carotid Stenosis by Atherosclerotic Cardiovascular Risk

Importance

Extracranial internal carotid artery stenosis (50-99% arterial narrowing) is an important risk factor for ischemic stroke. Yet, the benefits and harms of targeted screening for asymptomatic carotid artery stenosis (ACAS) have not been assessed in population-based studies.

Objective

To estimate the cost-effectiveness of one-time, targeted ACAS screening stratified by atherosclerotic cardiovascular disease (ASCVD) risk using the American Heart Association's Pooled Cohort Equations.

Design Setting and Participants

We developed a lifetime microsimulation model of ACAS and stroke for a hypothetical cohort representative of US adults aged 50-80 years without stroke history. We used the Cardiovascular Health Study to estimate the probability and severity of ACAS based on individual characteristics (e.g., age, sex, smoking status, blood pressure, and cholesterol). Stroke risks were functions of these characteristics and ACAS severity. In the model, individuals testing positive for >70% stenosis with Duplex ultrasound and a confirmatory diagnostic test undergo revascularization, which may reduce the risk of stroke but also introduces complication risks. Diagnostic performance parameters, revascularization benefits and risks, utility weights, and costs were estimated from published sources. Cost-effectiveness was assessed from the health care sector perspective using a $100,000/quality-adjusted life year (QALY) threshold.

Main Outcomes and Measures

Estimated stroke events prevented, lifetime costs, QALYs, and incremental cost-effectiveness ratios (ICERs) associated with ACAS screening. Costs (2023 USD) and QALYs were discounted at 3% annually.

Results

We found that screening individuals with a 10-year ASCVD risk >30% was the most cost-effective strategy, with an ICER of $89,000/QALY. This strategy would make approximately 11.9% of the population eligible for screening, averting an estimated 24,084 strokes. Results were sensitive to variations in the efficacy and complication risk of revascularization. In probabilistic sensitivity analysis, screening those in lower ASCVD risk groups (0-20%) only had a 0.6% chance of being cost-effective.

Conclusion and Relevance

A one-time screening may only be cost-effective for adults at a relatively high ASCVD risk. Our findings provide a framework that can be adapted as future clinical trial data continue to improve our understanding of the role of revascularization and intensive medical therapy in contemporary stroke prevention secondary to carotid disease.

Investigation of Combined Carotid Endarterectomy and Coronary Artery Bypass Graft Surgery Outcomes and Adverse Event Risk Factors in the Vascular Quality Initiative

OBJECTIVE

The purpose of this study was to investigate outcomes of simultaneous CEA and CABG utilizing the Vascular Quality Initiative (VQI). Additionally, we seek to investigate risks for both perioperative and long-term mortality and adverse neurological outcomes.

METHODS

All carotid endarterectomies in the VQI between January 2003 and May 2022 were queried. We identified 171,816 CEA in the database. We extracted 2 cohorts from these CEA. The first group was patients who underwent simultaneous carotid endarterectomy (CEA) and coronary artery bypass (CABG) (N = 3137). The second group encompassed patients who underwent CABG or percutaneous coronary artery angioplasty/stent within 5 years of ultimately undergoing CEA (N = 27,387). We investigated the following outcomes in a multivariable fashion: 1. Risks for mortality in long term follow-up for both cohorts combined; 2. Risks for ischemic event in the cerebral hemisphere ipsilateral to the CEA site after index hospital admission in follow up for both cohorts combined. Tertiary outcomes are also investigated in the manuscript.

RESULTS

On multivariable analysis, patients undergoing simultaneous combined CEA and CABG had equivalent long-term survival to patients who underwent coronary revascularization within 5 years of ultimately undergoing CEA. Five-year survival is noted to be 84.5% vs 86% with a Cox regression non-significant P-value (.203). Significant multivariable risks for reduced long term survival (P < .03 for all) included: advancing age (HR 2.48/year); smoking history (HR 1.26); Diabetes (HR 1.33); history of CHF (HR 1.66); history of COPD (HR 1.54); baseline renal insufficiency at the time of surgery (HR 1.30); anemia (HR1.64); lack of preoperative aspirin (HR 1.12); and lack of preoperative statin (HR 1.32); lack of patch placement at CEA site (HR 1.16); perioperative MI (HR 2.04); perioperative CHF (1.66); perioperative dysrhythmia (HR 1.36); cerebral reperfusion injury (HR 2.23); perioperative ischemic neurological event (HR 2.48); and lack of statin at discharge (HR 2.04). Amongst patients with documented neurological status in follow up, combined CEA and CABG had over 99% freedom from ischemic cerebral event ipsilateral to the CEA site after discharge.

CONCLUSIONS

Combined CEA and CABG provides excellent long-term mortality prevention in patients with co-existing severe coronary and carotid atherosclerosis. Simultaneous CEA and CABG provides equivalent stroke prevention and long-term survival to both a cohort of patients undergoing coronary revascularization within 5 years of CEA and patients undergoing isolated CEA or CABG in the literature. The two most impactful modifiable risk factors towards long-term stroke and mortality prevention for patients undergoing simultaneous CEA-CABG are patch placement at CEA site and adherence to statin medication therapy.

Carotid calcium burden derived from computed tomography angiography as a predictor of all-cause mortality after carotid endarterectomy

OBJECTIVE

Carotid endarterectomy (CEA) aims to reduce the risk of stroke in patients with atherosclerotic carotid disease. Preoperative risk assessments that predict complications are needed to optimize the care in this patient group. The current approach, namely relying solely on symptomatology and degree of stenosis, is outdated and calls for innovation. The Agatston calcium score was applied in several vascular specialties to assess cardiovascular risk profile but has been little studied in carotid surgery. It is hypothesized that a higher calcium burden at initial presentation equates to a worse prognosis attributable to an increased cerebrovascular and cardiovascular risk profile. The aim was to investigate the association between preoperative ipsilateral calcium score and postoperative all-cause mortality in patients undergoing CEA.

METHODS

This single-center retrospective cohort study included 89 patients who underwent CEA at a tertiary referral center between 2010 and 2018. Preoperative calcium scores were measured on contrast-enhanced computed tomography images with patient-specific Hounsfield thresholds at the level of the carotid bifurcation. The association between these calcium scores and all-cause mortality was analyzed using multivariable adjusted Cox proportional hazard analysis.

RESULTS

Cox proportional hazard analysis demonstrated a significant association between preoperative ipsilateral carotid calcium score and all-cause mortality (hazard ratio, 1.10; 95% confidence interval, 1.03-1.16; P = .003). After adjusting for age, preoperative estimated glomerular filtration rate, and diabetes mellitus, a significant association remained (hazard ratio, 1.07; 95% confidence interval, 1.00-1.15; P = .05).

CONCLUSIONS

A higher calcium burden was predictive of worse outcome, which might be explained by an overall poorer health status. These results highlight the potential of calcium measurements in combination with other traditional risk factors, for preoperative risk assessment and thus for improved patient education and care.

Diabetes mellitus and adverse outcomes after carotid endarterectomy: A systematic review and meta-analysis

BACKGROUND

There is still uncertainty regarding whether diabetes mellitus (DM) can adversely affect patients undergoing carotid endarterectomy (CEA) for carotid stenosis. The aim of the study was to assess the adverse impact of DM on patients with carotid stenosis treated by CEA.

METHODS

Eligible studies published between 1 January 2000 and 30 March 2023 were selected from the PubMed, EMBASE, Web of Science, CENTRAL, and ClinicalTrials databases. The short-term and long-term outcomes of major adverse events (MAEs), death, stroke, the composite outcomes of death/stroke, and myocardial infarction (MI) were collected to calculate the pooled effect sizes (ESs), 95% confidence intervals (CIs), and prevalence of adverse outcomes. Subgroup analysis by asymptomatic/symptomatic carotid stenosis and insulin/noninsulin-dependent DM was performed.

RESULTS

A total of 19 studies (n = 122,003) were included. Regarding the short-term outcomes, DM was associated with increased risks of MAEs (ES = 1.52, 95% CI: [1.15-2.01], prevalence = 5.1%), death/stroke (ES = 1.61, 95% CI: [1.13-2.28], prevalence = 2.3%), stroke (ES = 1.55, 95% CI: [1.16-1.55], prevalence = 3.5%), death (ES = 1.70, 95% CI: [1.25-2.31], prevalence =1.2%), and MI (ES = 1.52, 95% CI: [1.15-2.01], prevalence = 1.4%). DM was associated with increased risks of long-term MAEs (ES = 1.24, 95% CI: [1.04-1.49], prevalence = 12.2%). In the subgroup analysis, DM was associated with an increased risk of short-term MAEs, death/stroke, stroke, and MI in asymptomatic patients undergoing CEA and with only short-term MAEs in the symptomatic patients. Both insulin- and noninsulin-dependent DM patients had an increased risk of short-term and long-term MAEs, and insulin-dependent DM was also associated with the short-term risk of death/stroke, death, and MI.

CONCLUSIONS

In patients with carotid stenosis treated by CEA, DM is associated with short-term and long-term MAEs. DM may have a greater impact on adverse outcomes in asymptomatic patients after CEA. Insulin-dependent DM may have a more significant impact on post-CEA adverse outcomes than noninsulin-dependent DM. Whether DM management could reduce the risk of adverse outcomes after CEA requires further investigation.

Assessment of extracranial carotid artery disease using digital twins - A pilot study

To improve risk stratification in extracranial internal carotid artery disease (CAD), patients who would benefit maximally from revascularization must be identified. In cardiology, the fractional flow reserve (FFR) has become a reference standard for evaluating the functional severity of coronary artery stenosis, and noninvasive surrogates thereof relying on computational fluid dynamics (CFD) have been developed. Here, we present a CFD-based workflow using digital twins of patients' carotid bifurcations derived from computed tomography angiography for the noninvasive functional assessment of CAD. We reconstructed patient-specific digital twins of 37 carotid bifurcations. We implemented a CFD model using common carotid artery peak systolic velocity (PSV) acquired with Doppler ultrasound (DUS) as inlet boundary condition and a two-element Windkessel model as oulet boundary condition. The agreement between CFD and DUS on the PSV in the internal carotid artery (ICA) was then compared. The relative error for the agreement between DUS and CFD was 9% ± 20% and the intraclass correlation coefficient was 0.88. Furthermore, hyperemic simulations in a physiological range were feasible and unmasked markedly different pressure drops along two ICA stenoses with similar degree of narrowing under comparable ICA blood flow. Hereby, we lay the foundation for prospective studies on noninvasive CFD-based derivation of metrics similar to the FFR for the assessment of CAD.

Role of risk scoring systems in predicting life expectancy after carotid endarterectomy in asymptomatic patients

OBJECTIVE

The aim of this study is to compare and to test the performance of all available risk scoring systems (RSSs) designed to predict long-term survival rate in asymptomatic candidate patients for carotid endarterectomy (CEA) for significant carotid artery stenosis.

METHODS

Data on asymptomatic patients who underwent CEA in three high-volume centers were prospectively recorded. Through literature research using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations, six RSSs were identified for the intent of the study. Primary endpoints were 3- and 5-year survival rates after CEA. All items used as variables to compose multiple RSSs were applied to every patient in the study population. The 3- and 5-year mortality prediction rates for each score were assessed by sensitivity, specificity, and predictive negative and positive value calculation, as well as univariable Cox proportional hazard models with the Harrell C index.

RESULTS

During the study period, 825 CEAs in 825 asymptomatic patients were analyzed. All items used in RSSs were available in the dataset, with some concerns regarding their definition and application among RSSs. The 3- and 5-year survival rates of the study cohort were 94.5% and 90.3%, respectively. Among the six RSSs analyzed, no RSS demonstrated optimal results in terms of mortality rate prediction accuracy, although some scores had good diagnostic and risk of death precision.

CONCLUSIONS

RSSs, when used alone, fail to optimally detect postoperative life expectancy in asymptomatic CEA patient candidates. Further prospective controlled studies are needed to compose and validate RSSs with better calibration to predict outcomes.

Predictive Value of Complete Blood Count-Derived Inflammatory Markers for 5-Year Survival After Carotid Endarterectomy: Implications for Practice

Complete blood count inflammatory markers (CBC-IMs) have been associated with cardiovascular diseases and mortality. We aimed to evaluate the relationship between preoperative CBC-IMs and 5-year survival after carotid endarterectomy (CEA). Retrospective analysis of 411 consecutive patients who underwent CEA between 2004 and 2018 was done. CBC-IM included the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), lymphocyte-to-monocyte (LMR) ratio, and systemic immune-inflammation index (SII). Survival rate at 5 years was 79.8%. Age (hazard ratio (HR) = 1.05, P = .003), hemoglobin (HR = 0.78, P < .001), heart failure (HR = 2.91, P = .005), American Society of Anesthesiologists (ASA)-IV score (HR = 2.41, P = .043), and active neoplastic disease (HR = 2.61, P = .028) were independently related to survival. The discrimination of this model (C-statistic) was 0.698. Spline analysis showed a linear relationship between survival and NLR (P < .001), PLR (P < .001), and SII (P < .001). After adjusting for the baseline predictive score, there was a significant relationship between survival and NLR (HR = 1.191, P = .001), PLR (HR = 1.004, P = .017), and SII (HR = 1.001, P < .001). The addition of NLR, PLR, and SII to the survival model improved the continuous net reclassification index (c-NRI) by 0.29 (P = .028), 0.347 (P = .008), and 0.481 (P < .001), respectively, but not the C-statistic. CBC-IMs show a linear and independent relationship with 5-year survival after CEA and may moderately contribute to patient selection for this preventive intervention.

Gene polymorphism in tissue epidermal growth factor receptor (EGFR) influences clinical and histological vulnerability of carotid plaques

INTRODUCTION

Different models have been proposed for the prediction of the risk/benefit ratio of surgery in patients with carotid atheromasic disease, mainly based on clinical patients' characteristics and risk factors, but no definite biological markers predictive of plaque instability and disease evolution have emerged so far, able to help the surgeon in the choice and timing of treatment. The main purpose of the present study was to assess the role of the polymorphism for genes commonly implicated in cell proliferation and neoangiogenesis in the clinical and histopathological carotid plaque vulnerability.

MATERIALS AND METHODS

We retrospectively studied 29 consecutive patients who underwent carotid endarterectomy in 6 months. All histological variables were collected, as well as patients' cardiovascular risk factors, clinical presentation, and brain computed tomography (CT) for the presence of ischemic lesions. Next-Generation Sequencing (NGS) was performed on 10-µm FFPE sections by means of a multi-gene panel used for sequencing 343 amplicons in 28 genes.

RESULTS

Among the gene variants observed, the polymorphism p.(Gln787=) in the EGFR gene was inversely correlated with intraplaque hemorrhage (p = 0.014), but also with the presence of ischemic brain lesions at CT (p = 0.001). Also p.(Gly105=) polymorphism in the IDH1 gene was inversely correlated with the presence of ischemic brain lesions (p = 0.038).

CONCLUSIONS

The variant p.(Gln787=) in the EGFR gene seems to play a role in plaque stability in patients with carotid atheromasic disease, on both histopathological and clinical grounds, probably acting on plaque matrix remodeling. This can open new scenarios on the pre-surgical management of these patients.

External Validation of Risk Prediction Models to Improve Selection of Patients for Carotid Endarterectomy

BACKGROUND AND PURPOSE

The net benefit of carotid endarterectomy (CEA) is determined partly by the risk of procedural stroke or death. Current guidelines recommend CEA if 30-day risks are <6% for symptomatic stenosis and <3% for asymptomatic stenosis. We aimed to identify prediction models for procedural stroke or death after CEA and to externally validate these models in a large registry of patients from the United States.

METHODS

We conducted a systematic search in MEDLINE and EMBASE for prediction models of procedural outcomes after CEA. We validated these models with data from patients who underwent CEA in the American College of Surgeons National Surgical Quality Improvement Program (2011-2017). We assessed discrimination using C statistics and calibration graphically. We determined the number of patients with predicted risks that exceeded recommended thresholds of procedural risks to perform CEA.

RESULTS

After screening 788 reports, 15 studies describing 17 prediction models were included. Nine were developed in populations including both asymptomatic and symptomatic patients, 2 in symptomatic and 5 in asymptomatic populations. In the external validation cohort of 26 293 patients who underwent CEA, 702 (2.7%) developed a stroke or died within 30-days. C statistics varied between 0.52 and 0.64 using all patients, between 0.51 and 0.59 using symptomatic patients, and between 0.49 to 0.58 using asymptomatic patients. The Ontario Carotid Endarterectomy Registry model that included symptomatic status, diabetes, heart failure, and contralateral occlusion as predictors, had C statistic of 0.64 and the best concordance between predicted and observed risks. This model identified 4.5% of symptomatic and 2.1% of asymptomatic patients with procedural risks that exceeded recommended thresholds.

CONCLUSIONS

Of the 17 externally validated prediction models, the Ontario Carotid Endarterectomy Registry risk model had most reliable predictions of procedural stroke or death after CEA and can inform patients about procedural hazards and help focus CEA toward patients who would benefit most from it.

A single center's 15-year experience with palliative limb care for chronic limb threatening ischemia in frail patients

OBJECTIVE

Our institution's multidisciplinary Prevention of Amputation in Veterans Everywhere (PAVE) program allocates veterans with critical limb threatening ischemia (CLTI) to immediate revascularization, conservative, primary amputation or palliative limb care based on previously published criteria. These four groups align with the approaches outlined by the Global Guidelines for management of CLTI. The current study delineates the natural history of the palliative limb care group of patients and quantifies procedural risks and outcomes.

METHODS

Veterans prospectively enrolled into the palliative limb cohort of our PAVE program between January 2005 and January 2020 were analyzed. The primary outcome was mortality. Secondary outcomes included overall and limb-related readmissions, limb loss and wound healing. Clinical Frailty Score (CFS) was calculated and 5-year expected mortalities were estimated using the Veterans Administration Quality Enhancement Research Initiative (VA QUERI) tool. Regression analysis was performed to establish associations among the following variables: mortality, WIfI score, Clinical Frailty Score, overall admissions and limb-related admissions.

RESULTS

The PAVE program enrolled 1158 limbs over 15 years. 157 (13.5%) limbs in 145 patients were allocated to the palliative limb care group. The overall mortality of the group was 88.2% (median 3.5 months; range 0-91 months). Of the patients that expired, 50% (n=64) died within 3 months of enrollment. The predicted 5-year mortality for the group was 66%. The average frailty score of the group was 6.2, denoting someone who is moderately to severely frail. Based on CFS, 106 patients were considered frail while 39 were considered not frail. There was no difference in mortality between frail and non- frail patients, however there was a statistically significant difference in early mortality (<3 months), 56.2% vs 37.5% (p = 0.032), respectively. The 30-day limb-related readmission rate was 4.7%. Eventual major amputation was necessary in 18 (11.5%) limbs. Wound healing occurred in 30 patients (20.6%). Regression analysis demonstrated no association between frailty score and mortality (r = 0.55, p = 0.159) or between WIfI score and mortality (r = 0.0165, p = 0.98). There was a significant association between WIfI score and limb-related admissions (r = 0.97, p <0.001).

CONCLUSION

Frail, chronic limb threatening ischemia patients have a high early mortality and a low risk of limb-related complications. They also have a low incidence of deferred primary amputation or limb-related readmissions. In our cohort, the vast majority of patients died within a few months of enrollment without needing an amputation. A comprehensive approach to the management of CLTI patients should include a palliative limb care option as a significant proportion of these patients have limited survival and can potentially avoid unnecessary surgery or major amputation.

Hypothesis of "stroke-stop" formula: a tool for risk index determination in development of acute cerebrovascular disease in asymptomatic individuals with carotid stenosis

Background

Extracranial carotid artery disease is considered a risk factor for developing acute cerebrovascular diseases. The paper suggests the “Stroke-Stop” formula as hypothesis for the determination of the risk of developing stroke in asymptomatic individuals with carotid stenosis. The formula is based on a mathematical calculation of the major risk factors for stroke: the degree of ICA (internal carotid artery) stenosis, the morphological structure of the atherosclerotic plaque and the level of lipoprotein-associated phospholipase A2 (Lp-PLA2) concentration.

Methods

The cross sectional study included 70 patients with atherosclerotic ICA stenosis. Among vascular inflammatory markers, Lp-PLA2 was determined with concentration 252.7–328.6 mg/l. The obtained results were evaluated using descriptive statistics (the frequency, percentage ratio) as well as the one-way analysis of variance (ANOVA) and chi-square test.

Results

The risk of stroke development is eminently increasing with the progression of ICA stenosis and elevation of Lp-PLA2 levels. In patients with echolucent plaque, the risk of stroke development was significantly higher in correlation with patients with echogenic plaque. Based on calculations using “Stroke-Stop” formula, three main groups were generated: low (< 70 points), medium (70–100 points) and high (> 100 points) risk of stroke development.

Conclusions

Hypothesis of “Stroke-Stop” formula is proposed for better selection of patients who should be indicated for surgical treatment and will be evaluated in prospective study. In order to verify this hypothesis, we plan to do prospective study using “Stroke-Stop” formula for ipsilateral annual stroke rate in asymptomatic individuals with carotid stenosis who receive conservative therapy.

Stenosis, ulceration of the atherosclerotic plaque and Lp-PLA2 concentration are calculated

3 groups of stroke risk development were set (low, medium and high)

Proposed formula form personalized approach to the diagnosis and prevention of stroke

Management of patients with asymptomatic carotid stenosis may need to be individualized: a multidisciplinary call for action. Republication of J Stroke 2021;23:202-212

The optimal management of patients with asymptomatic carotid stenosis (ACS) is the subject of extensive debate. According to the 2017 European Society for Vascular Surgery guidelines, carotid endarterectomy should (Class IIa; Level of Evidence: B) or carotid artery stenting may be considered (Class IIb; Level of Evidence: B) in the presence of one or more clinical/imaging characteristics that may be associated with an increased risk of late ipsilateral stroke (e.g. silent embolic infarcts on brain computed tomography/magnetic resonance imaging, progression in the severity of ACS, a history of contralateral transient ischemic attack/stroke, microemboli detection on transcranial Doppler, etc.), provided documented perioperative stroke/death rates are <3% and the patient's life expectancy is >5 years. Besides these clinical/imaging characteristics, there are additional individual, ethnic/racial or social factors that should probably be evaluated in the decision process regarding the optimal management of these patients, such as individual patient needs/patient choice, patient compliance with best medical treatment, patient sex, culture, race/ethnicity, age and comorbidities, as well as improvements in imaging/operative techniques/outcomes. The present multispecialty position paper will present the rationale why the management of patients with ACS may need to be individualized.

Management of Patients with Asymptomatic Carotid Stenosis May Need to Be Individualized: A Multidisciplinary Call for Action

The optimal management of patients with asymptomatic carotid stenosis (ACS) is the subject of extensive debate. According to the 2017 European Society for Vascular Surgery guidelines, carotid endarterectomy should (Class IIa; Level of Evidence: B) or carotid artery stenting may be considered (Class IIb; Level of Evidence: B) in the presence of one or more clinical/imaging characteristics that may be associated with an increased risk of late ipsilateral stroke (e.g., silent embolic infarcts on brain computed tomography/magnetic resonance imaging, progression in the severity of ACS, a history of contralateral transient ischemic attack/stroke, microemboli detection on transcranial Doppler, etc.), provided documented perioperative stroke/death rates are <3% and the patient’s life expectancy is >5 years. Besides these clinical/imaging characteristics, there are additional individual, ethnic/racial or social factors that should probably be evaluated in the decision process regarding the optimal management of these patients, such as individual patient needs/patient choice, patient compliance with best medical treatment, patient sex, culture, race/ethnicity, age and comorbidities, as well as improvements in imaging/operative techniques/outcomes. The present multispecialty position paper will present the rationale why the management of patients with ACS may need to be individualized.

Frailty Measurement and Implications for Cerebrovascular Disease Management in a Veteran Based Population

BACKGROUND

Rapid and objective preoperative assessment of patients undergoing carotid endarterectomy (CEA) remains difficult and variable. The Risk Analysis Index (RAI) is a validated medical record-based assessment of frailty that has been used to predict clinical outcomes for patients undergoing surgical procedures including CEA. We applied RAI to a veteran population following CEA for asymptomatic cerebrovascular disease and examined the factors related to post-operative morbidity and mortality.

METHODS

After obtaining IRB approval, Veteran Affairs Surgical Quality Improvement Program data was queried for CEA procedures from 2002 to 2015 for ICD-9 codes indicating asymptomatic patients. RAI was then calculated based on Veteran Affairs Surgical Quality Improvement Program variable medical record extraction. Three groupings of patients were undertaken including non-frail (RAI < 30), frail (RAI 30-34) and very frail (RAI ≥ 35). Chi squared and ANOVA were used to assess cohort differences. Binary logistic regression was used to evaluate predictors of post-operative stroke, myocardial infarction (MI), any complication, and death.

RESULTS

Between 2002 and 2015, 37,873 asymptomatic patients underwent CEA. Over 98% (37,266) of the patients were male with an average age of 68.3 ± 8.55 years. The cohorts contained 82.8% (n = 31,362), 12.4% (n = 4,678), and 4.8% (n = 1,833) for the non-frail, frail and very frail groups respectively. Frailty was associated with increased rates of post-operative stroke, MI, any complication, death, and longer hospital length of stay (P< 0.001). Operative time did not significantly differ between the groups. Increasing frailty was associated with having one or more complications (OR 1.69, 95% CI 1.50-1.90 for frail and OR 2.79, 95% CI 2.41-3.24 for very frail, (P< 0.001), post-operative stroke in frail (OR 1.33 95% CI 1.06-1.67) and very frail (OR 1.57 1 95% CI 1.14-2.16) patients, and MI in both frail (OR 1.68, CI 1.17-2.43) and very frail (OR 3.73, CI 2.52-5.51) patients. Frailty was also significantly associated with death with in very frail patients (OR 4.14, 95% CI 3.00-5.71, P< 0.001).

CONCLUSION

Increasing frailty as determined by RAI was associated with worse post-operative outcomes in asymptomatic patients undergoing CEA. Higher RAI score cohorts were associated with higher rates of postoperative stroke, MI, complications, and death. We recommend the use of this frailty index as a screening tool to guide risk discussions with asymptomatic patients undergoing CEA.

[Asymptomatic carotid stenosis: What is new?]

In industrialized countries, stroke is still the most common disease that leads to permanent disability. Of the 250 000 strokes that occur annually in Germany, in about 80 % are cerebral ischemia. Approximately 15 % of these ischemias are caused by lesions of the extracranial internal carotid artery, so optimal treatment of extracranial carotid stenosis is essential 1. This continues to be the subject of a controversial debate, as optimized drug therapy has led to a significant reduction in risk.In 2020, the multidisciplinary S3 guideline for the management of extracranial carotid stenoses was updated. In the following, current aspects and new recommendations for asymptomatic carotid stenosis are presented and important innovations of the guideline are explained.

Epidemiology of atherosclerotic carotid artery disease

Atherosclerotic carotid artery disease is a significant cause of stroke in the United States and globally. Its prevalence increases with age and it is more prevalent in men and White and Native-American populations. However, the outcomes related to carotid disease are worse in women and Black patients. Research suggests the disparities exist due to a multitude of factors, including disease pathophysiology, access to care, provider bias, and socioeconomic status. The prevalence of carotid stenosis in the general population is low (3%), and routine screening for carotid stenosis is not recommended in adults. Randomized clinical trials have shown benefits of stroke risk reduction with surgery (carotid endarterectomy or stenting) for symptomatic patients. Management is controversial in asymptomatic patients, as modern medical management has results equivalent to those of surgery and ongoing randomized clinical trials will address this important question. Carotid surgery is not appropriate in asymptomatic patients with limited life expectancy. Future work should explore comprehensive care models for care of patients with carotid disease and assessment of patient-reported outcomes to measure quality of care.

Editor's Choice - Development and Validation of a Multivariable Prediction Model of Peri-operative Mortality in Vascular Surgery: The New Zealand Vascular Surgical Risk Tool (NZRISK-VASC)

OBJECTIVE

Risk calculators and prediction models are available to assist clinicians and patients with peri-operative decision making to optimise outcomes. In a vascular surgical setting, the majority of these models is based on open AAA repair outcomes, and in general their clinical use is limited. The objective of this study was to develop and validate a simple and accurate vascular surgical risk prediction model.

METHODS

A national administrative database was accessed to collect information on all adult patients undergoing vascular surgery between 1 July 2011 and 30 June 2016 in New Zealand. The primary outcomes were mortality at 30 days, one year, and two years. Previously established covariables including American Society of Anaesthesiologists (ASA) physical status score, sex, surgical urgency, cancer status and ethnicity were tested, and other covariables such as smoking status, presence of renal failure, diabetes, anatomical site of operation, structure operated, and type of procedures (open or endovascular) were explored. LASSO regression was used to select variables for inclusion in the model.

RESULTS

A total of 21 597 cases formed the final risk prediction models, with covariables including ASA score, gender, surgical urgency, cancer status, presence of renal failure, diabetes, anatomical site, structure operated, and endovascular procedure. The area under the receiver operating curve (AUROC) for 30 day, one year, and two year mortality using L-min model was 0.869, 0.833, and 0.824, respectively, demonstrating very good discrimination. Calibration with the validation dataset was also excellent, with slopes of 0.971, 1.129, and 1.011, respectively, and McFadden's pseudo-R² statistics of 0.250, 0.227, and 0.227, respectively.

CONCLUSION

A simple and accurate multivariable risk calculator for vascular surgical patients was developed and validated using the New Zealand national dataset, with excellent discrimination and calibration for 30 day, one year, and two year mortality.

Meta-Analysis Comparing the Frequency of Carotid Artery Stenosis in Patients With Atrial Fibrillation and Vice Versa

Atrial fibrillation (AF) and carotid stenosis (CS) can coexist and this association has been reported to result in a higher risk of stroke than attributed to either condition alone. Here we aimed to summarize the data on the association of CS and AF. MEDLINE and Embase were searched to identify all published studies providing relevant data through February 27, 2020. Random-effects meta-analysis method was used to pool estimates of prevalence. Heterogeneity was assessed by mean I-squared statistic. Forty-eight studies were included, 20 reporting on the prevalence of carotid disease in a pooled population of 49,070 AF patients, and 28 on the prevalence of AF in a total of 2,288,265 patients with carotid disease. The pooled prevalence of CS in AF patients was 12.4% (95% confidence interval [CI] 8.7 to 16.0, I² 93%; n = 3,919), ranging from 4.4% to 24.3%. The pooled prevalence of carotid plaque was 48.4% (95% CI 35.2 to 61.7, I² = 99%; n = 4292). The prevalence of AF in patients with CS was 9.3% (95% CI 8.7 to 10.0, I² 99%; n = 2,286,518), ranging from 3.6% to 10.0%. This prevalence was much higher (p <0.001) in patients undergoing carotid artery stenting (12.7%, 95% CI 11.3 to 14.02, I² 38.3%) compared with those undergoing carotid endarterectomy (6.9%, 95% CI 8.3 to 10.4, I² 94.1%). There was no difference in AF prevalence between patients with CS, with and without previous cerebrovascular event (p >0.05). In conclusion, AF and CS frequently coexist, with about one in ten patients with AF having CS, and vice versa. In addition, nonstenotic carotid disease is present in about half of AF patients. These findings have important implications for AF screening in patients with CS, stroke prevention, and the opportunities to intervene on common risk factors.

Frailty as measured by the Risk Analysis Index is associated with long-term death after carotid endarterectomy

OBJECTIVE

The role of carotid endarterectomy (CEA) continues to be debated in the age of optimal medical therapy, particularly for patients with limited life expectancy. The Risk Analysis Index (RAI) measures frailty, a syndrome of decreased physiologic reserve, which increases vulnerability to adverse outcomes. The RAI better predicts surgical complications, nonhome discharge, and death than age or comorbidities alone. We sought to measure the association of frailty, as measured by the RAI, with postoperative in-hospital stroke, long-term stroke, and long-term survival after CEA. We also sought to determine how postoperative stroke interacts with frailty to alter survival trajectory after CEA.

METHODS

We queried the Vascular Quality Initiative CEA procedure and long-term data sets (2003-2017) for elective CEAs with complete RAI case information. For all analyses, the cohort was divided into asymptomatic and symptomatic carotid stenosis. Scoring was defined as not frail (RAI <30), frail (RAI 30-34), and very frail (RAI ≥35). Mortality information through December 2017 was obtained from the Social Security Death Index. Multivariable models (logistic and Cox proportional hazards regressions) were used to study the association of frail and very frail patients with the outcomes of interest. In a post hoc analysis, we created Kaplan-Meier curves to analyze patient mortality after CEA as well as after postoperative stroke.

RESULTS

Of the 42,869 included patients, 17,092 (39.9%) were female, and 38,395 (89.6%) were white. There were 25,673 (59.9%) patients assigned to the asymptomatic stenosis group and 17,196 (40.1%) patients in the symptomatic stenosis group. Frailty was not associated with perioperative or long-term postoperative stroke. The risk of long-term mortality was significantly higher for frail (hazard ratio, 1.9 [1.7-2.3]) and very frail (hazard ratio, 3.1 [2.6-3.7]) asymptomatic patients; symptomatic frail and very frail patients also had a two to three times increased risk of long-term mortality. Frail and very frail patients had two to three times the risk for long-term mortality compared with patients who were not frail. Postoperative stroke negatively affected the mortality trajectory for all patients in the cohort, regardless of frailty status.

CONCLUSIONS

RAI score is not associated with postoperative stroke; however, frail and very frail status is associated with decreased long-term survival in an incremental fashion based on increasing RAI. RAI assessment should be considered in the preoperative decision-making for patients undergoing CEA to ensure long-term survival and optimal surgical outcomes vs medical management.

Shifts in gut microbiome and metabolome are associated with risk of recurrent atrial fibrillation

Alternations of gut microbiota (GM) in atrial fibrillation (AF) with elevated diversity, perturbed composition and function have been described previously. The current work aimed to assess the association of GM composition with AF recurrence (RAF) after ablation based on metagenomic sequencing and metabolomic analyses and to construct a GM-based predictive model for RAF. Compared with non-AF controls (50 individuals), GM composition and metabolomic profile were significantly altered between patients with recurrent AF (17 individuals) and non-RAF group (23 individuals). Notably, discriminative taxa between the non-RAF and RAF groups, including the families Nitrosomonadaceae and Lentisphaeraceae, the genera Marinitoga and Rufibacter and the species Faecalibacterium spCAG:82, Bacillus gobiensis and Desulfobacterales bacterium PC51MH44, were selected to construct a taxonomic scoring system based on LASSO analysis. After incorporating the clinical factors of RAF, taxonomic score retained a significant association with RAF incidence (HR = 2.647, P = .041). An elevated AUC (0.954) and positive NRI (1.5601) for predicting RAF compared with traditional clinical scoring (AUC = 0.6918) were obtained. The GM-based taxonomic scoring system theoretically improves the model performance, and the nomogram and decision curve analysis validated the clinical value of the predicting model. These data provide novel possibility that incorporating the GM factor into future recurrent risk stratification.