Effective Stroke Prevention in Patients with Symptomatic Carotid Stenosis

Safety of Carotid Endarterectomy for Symptomatic Stenosis by Age: Meta-Analysis With Individual Patient Data

BACKGROUND

There is uncertainty whether elderly patients with symptomatic carotid stenosis have higher rates of adverse events following carotid endarterectomy. In trials, recurrent stroke risk on medical therapy alone increased with age, whereas operative stroke risk was not related. Few octogenarians were included in trials and there has been no systematic analysis of all study types. We aimed to evaluate the safety of carotid endarterectomy in symptomatic elderly patients, particularly in octogenarians.

METHODS

We did a systematic review and meta-analysis of studies (from January 1, 1980 through March 1, 2022) reporting post carotid endarterectomy risk of stroke, myocardial infarction, and death in patients with symptomatic carotid stenosis. We included observational studies and interventional arms of randomized trials if the outcome rates (or the raw data to calculate these) were provided. Individual patient data from 4 prospective cohorts enabled multivariate analysis.

RESULTS

Of 47 studies (107 587 patients), risk of perioperative stroke was 2.04% (1.94-2.14) in octogenarians (390 strokes/19 101 patients) and 1.85% (1.75-1.95) in nonoctogenarians (1395/75 537); P=0.046. Perioperative death was 1.09% (0.94-1.25) in octogenarians (203/18 702) and 0.53% (0.48-0.59) in nonoctogenarians (392/73 327); P<0.001. Per 5-year age increment, a linear increase in perioperative stroke, myocardial infarction, and death were observed; P=0.04 to 0.002. However, during the last 3 decades, perioperative stroke±death has declined significantly in octogenarians (7.78% [5.58-10.55] before year 2000 to 2.80% [2.56-3.04] after 2010); P<0.001. In Individual patient data multivariate-analysis (5111 patients), age ≥85 years was independently associated with perioperative stroke (P<0.001) and death (P=0.005). Yet, survival was similar for octogenarians versus nonoctogenarians at 1-year (95.0% [93.2-96.5] versus 97.5% [96.4-98.6]; P=0.08), as was 5-year stroke risk (11.93% [9.98-14.16]) versus 12.78% [11.65-13.61]; P=0.24).

CONCLUSIONS

We found a modest increase in perioperative risk with age in symptomatic patients undergoing carotid endarterectomy. As stroke risk increases with age when on medical therapy alone, our findings support selective urgent intervention in symptomatic elderly patients.

Influences of age and gender on operative risks following carotid endarterectomy: A systematic review and meta-analysis

OBJECTIVES

This review aims to undertake a comprehensive review of the literature and investigate associations of age and gender on 30 days post carotid endarterectomy (CEA) and up to 5 years post CEA stroke, death, and combined stroke and death.

DESIGN

A systematic review and meta-analysis.

METHODS

Three main electronic databases including the Cochrane Library, MEDLINE, and Embase were searched from their inception to July 2022. Studies examining operative risks (i.e., stroke, death, and combined stroke and death following CEA) linked to age or gender were included. Two independent reviewers were responsible for study selection, quality assessment, and data extraction. Odds ratio (OR) and 95% confidence interval (CI) of all outcomes were calculated.

RESULTS

44609 studies were retrieved from the search. There were 127 eligible studies (80 studies of age, 72 studies of gender, 25 studies of age and gender) for pooling in the meta-analysis. With regards to stroke and death risks within 30 days post CEA; patients aged ≥75 had higher death (OR 1.38; 95% CI 1.10-1.75) than patients aged <75. Patients aged ≥80 had higher stroke risk (OR 1.17; 95% CI 1.07-1.27) and death risk (OR 1.85; 95% CI 1.48-2.30) particular in asymptomatic patients (OR 2.4; 95% CI 1.56-3.81). Pooled effect estimates by gender, at 30 days post CEA, showed that female was associated with increased risk of stroke (OR 1.28; 95% CI 1.16-1.40), with more risk in asymptomatic female patients (OR 1.51; 95% CI 1.14-1.99).

CONCLUSIONS

This meta-analysis highlights that older people is associated with increased stroke risk, particularly asymptomatic octogenarians who had higher likelihood of death within 30 days post CEA. In addition, female especially those with asymptomatic carotid stenosis had greater likelihood of stroke within 30 days post CEA surgery.

Modifications in Near Infrared Spectroscopy for Cerebral Monitoring During Carotid Endarterectomy in Asymptomatic and Symptomatic Patients

BACKGROUND

To evaluate trends and differences in Near Infrared Spectroscopy (NIRS) monitoring during carotid endarterectomy (CEA) in patients affected by asymptomatic and symptomatic carotid artery stenosis, to predict postoperative neurological complications (PNCs).

METHODS

NIRS data of CEAs performed in a University Hospital were retrospectively reviewed. All the interventions were performed under general anesthesia and patients with intraoperative complications were excluded. Mean regional Oxygen Saturation Index (rSO₂), pre-clamp values (mean baseline value, MBv and Single Mark Baseline value, SMBv) were collected and compared to the lowest rSO₂ values during carotid cross-clamp (LSO₂v) calculated within 3 min (percentage drop, PD). ROC curve analysis with Youden's Test was performed to determine the best threshold value of PD, in order to identify PNCs in both asymptomatic and symptomatic groups.

RESULTS

Between 2007 and 2015, a total of 399 CEAs were consecutively performed with NIRS monitoring. Three-hundred-seventy-two CEAs in 355 patients were reviewed. Asymptomatic stenoses were 291 (81.9%), eleven (2.9%) PNC were registered (5 in asymptomatic and 6 in symptomatic group). Asymptomatic and symptomatic diseases had different MBv (69.5 ± 7.5 vs. 71.8 ± 6.9, respectively; P = 0.011) and similar rSO₂ value during carotid clamping (63.7 ± 8.0 vs. 63.7 ± 6.7, respectively: P = 0.958). Asymptomatic patients experiencing PNCs had a greater PD than non-PNCs group (20.5 ± 10.2% vs. 12.5 ± 7.6%, respectively using MBv as baseline value; P = 0.002), in contrast, in symptomatic patients, in which a low PD was associated with PNCs, it does not reach statistical significance (using MBv, 12.6 ± 5.4% vs. 14.8 ± 6.7%, respectively; P= 0.476). In order to detect PNCs, ROC analysis revealed an optimal PD cut-off value of -17% in asymptomatic CEAs. (Sensibility (Se) 0.80, Specificity (Sp) 0.76, PPV 0.05, NPV 0.99, Youden's index 0.56; P = 0.020) In symptomatic a threshold value of -9% was found, without reaching statistical significance.

CONCLUSIONS

NIRS as cerebral monitoring during CEA can predict PNCs in asymptomatic stenosis. Asymptomatic and symptomatic groups differ in baseline and intraprocedural cut-off values to detect an augmented PNCs risk.

Asymptomatic and symptomatic carotid stenosis: an obsolete classification?

Since many years, clinical decisions about the management of patients with carotid stenosis have been based on the distinction between "asymptomatic" and "symptomatic" presentations. This was also reflected by the design of previous studies on the surgical versus conservative treatment and of current studies on interventional treatment versus surgery. Both terms, however, only address different phases of activity of the one and the same condition and blur the significant message that carotid stenosis is a most important marker of systemic atherosclerosis, which is accompanied by a much higher risk of cardiovascular events rather than stroke. As a consequence, early diagnosis and followup during best medical treatment, life-style management, regular cardiovascular assessment, and good control of all vascular risk factors should be recommended in all patients with carotid stenosis-whether identified in the long-lasting "silent" or short-lasting "vulnerable" period lasting only a few weeks after cerebral ischemia. Patients in this short time window benefit from additional carotid intervention, under the condition of an individually favorable benefit-risk ratio ("individual vulnerability").

Early acute hemispheric stroke after carotid endarterectomy. Pathogenesis and management

PURPOSE

A major stroke after carotid endareterectomy (CEA) is an event that should be managed according to a planned strategy. Literature data on this issue are not definitive. We reviewed our series in the attempt to define an algorithm of treatment if this complication occurs.

METHODS

A consecutive series of 413 CEAs in 390 patients was considered. All operations were performed under general anaesthesia and EEG monitoring. An indwelling shunt was inserted only according to EEG changes. Direct closure of the arteriotomy was performed in all cases. Intraoperative ultrasound was not routinely employed before 2004. Patients who suffered from the new onset of an ischaemic hemispheric deficit or the worsening of a pre-existing deficit within 72 h after surgery were included in the present study.

RESULTS

Sixteen patients (3.9%) suffered from perioperative stroke. Seven patients presented neurological deficits that rapidly and spontaneously resolved. In nine cases (2.2%) a major stroke occurred. Acute occlusion of the internal carotid artery (ICA), with or without embolic blocking of the omolateral M1 segment, occurred in eight cases; in one case a patent ICA was associated with the occlusion of two frontal branches of the omolateral middle cerebral artery. Seven cases were reoperated on. The ICA was reopened in all these cases except one. Among these seven cases, three (42%) had a good outcome.

CONCLUSIONS

A major stroke after CEA is caused, in most of cases, by the acute ICA occlusion with or without intracerebral embolic occlusion. Reopening of the occluded ICA gives good results when intracerebral vessels are patent and when the occluded ICA is satisfactorily reopened. An algorithm of planned reactions in case of perioperative stroke is finally proposed.

[Carotid stenosis: is the distinction between "symptomatic" and "asymptomatic" obsolete?]

Carotid stenosis is common, especially among patients with vascular risk factors. The usual distinction between "symptomatic" and "asymptomatic" corresponds to older studies on the surgical vs. conservative treatment and to newer studies on interventional treatment (angioplasty with/without stent vs. surgery). However, both forms only describe different stages of activity of the same disease. They are markers of a systemic atherosclerosis, which results in a high risk of cardiovascular events in particular. All patients with carotid stenosis profit from regular clinical and duplexsonographic follow-up-studies of the brain arteries, cardiovascular assessment and good control of all vascular risk factors. Patients with carotid stenosis may profit from carotid intervention, if this takes place shortly after onset of associated cerebral ischemia and/or if there is a favorable benefit-risk ratio.

Carotid Endarterectomy: Is It Still a Gold Standard?

Extracranial internal carotid artery stenosis accounts for 15-20% of ischemic strokes. Carotid endarterectomy has high efficacy in stroke prevention in selected patients with symptomatic (age <80 years) and asymptomatic carotid stenosis (age <75 years). Randomized clinical trials demonstrated that carotid endarterectomy reduces the stroke risk, compared to medical therapy alone, for patients with 70-99% symptomatic stenosis with 16% absolute risk reduction at 5 years. The benefit for patients with 50-69% symptomatic stenosis is lower i.e. absolute risk reduction 4.6% at 5 years. Endarterectomy is not indicated for symptomatic patients with <50% stenosis. There is no need for time-delay for surgery in patients after transient ischemic attack or minor stroke. Patients with more extensive strokes or hemorrhage should undergo surgery after 4-6 weeks following initial symptoms. Carotid endarterectomy for asymptomatic stenosis reduces the risk of ipsilateral stroke, and any stroke, by approximately 30% over 3 years. However, the absolute risk reduction is small over the first few years and decision should be based on individual institutional experience. In all situations, the best medical therapy should accompany surgery. In the recent years, appearance of angioplasty, stenting, and distal protection procedures provides competitive alternatives to classical endarterectomy. However, long-term benefits of carotid angioplasty should be confirmed by bigger, randomized, comparative clinical trials.

Reproducibility of histological assessment of carotid plaque: implications for studies of carotid imaging

BACKGROUND

Thromboembolism from carotid plaque is an important cause of stroke. Identification of unstable plaque would therefore be clinically useful. Unfortunately, studies of carotid plaque imaging have shown poor agreement with histology. However, this may be due to inconsistent methods and the variability of assessments of carotid plaque histology, rather than inadequate imaging.

METHODS

We assessed the reproducibility of histological assessment in 60 plaques, and section-to-section variability along the length of 26 plaques.

RESULTS

Kappa values ranged from 0.35 to 0.89 and from 0.44 to 0.68, respectively, for intra- and inter-observer reproducibility. There was considerable section-to-section variability within plaques.

CONCLUSIONS

The accuracy of imaging of carotid plaque morphology will be underestimated unless variability in the histology assessment is taken into account.