Deferred Urgency Carotid Artery Stenting in Symptomatic Patients: Clinical Lessons and Biomarker Patterns from a Prospective Registry

Clinical Outcomes of Second- versus First-Generation Carotid Stents: A Systematic Review and Meta-Analysis

Background: Single-cohort studies suggest that second-generation stents (SGS; “mesh stents”) may improve carotid artery stenting (CAS) outcomes by limiting peri- and postprocedural cerebral embolism. SGS differ in the stent frame construction, mesh material, and design, as well as in mesh-to-frame position (inside/outside). Objectives: To compare clinical outcomes of SGS in relation to first-generation stents (FGSs; single-layer) in CAS. Methods: We performed a systematic review and meta-analysis of clinical studies with FGSs and SGS (PRISMA methodology, 3302 records). Endpoints were 30-day death, stroke, myocardial infarction (DSM), and 12-month ipsilateral stroke (IS) and restenosis (ISR). A random-effect model was applied. Results: Data of 68,422 patients from 112 eligible studies (68.2% men, 44.9% symptomatic) were meta-analyzed. Thirty-day DSM was 1.30% vs. 4.11% (p < 0.01, data for SGS vs. FGS). Among SGS, both Casper/Roadsaver and CGuard reduced 30-day DSM (by 2.78 and 3.03 absolute percent, p = 0.02 and p < 0.001), whereas the Gore stent was neutral. SGSs significantly improved outcomes compared with closed-cell FGS (30-day stroke 0.6% vs. 2.32%, p = 0.014; DSM 1.3% vs. 3.15%, p < 0.01). At 12 months, in relation to FGS, Casper/Roadsaver reduced IS (−3.25%, p < 0.05) but increased ISR (+3.19%, p = 0.04), CGuard showed a reduction in both IS and ISR (−3.13%, −3.63%; p = 0.01, p < 0.01), whereas the Gore stent was neutral. Conclusions: Pooled SGS use was associated with improved short- and long-term clinical results of CAS. Individual SGS types, however, differed significantly in their outcomes, indicating a lack of a “mesh stent” class effect. Findings from this meta-analysis may provide clinically relevant information in anticipation of large-scale randomized trials.

Timing of Carotid Intervention in Symptomatic Carotid Artery Stenosis: A Systematic Review and Meta-Analysis

OBJECTIVE

This review aimed to analyse the timing of carotid endarterectomy (CEA) and carotid artery stenting (CAS) after the index event as well as 30 day outcomes at varying time periods within 14 days of symptom onset.

METHODS

A systematic review was performed according to the Preferred Reporting Items for Systematic reviews and Meta-analysis statement, comprising an online search of the Medline and Cochrane databases. Methodical quality assessment of the included studies was performed. Endpoints included procedural stroke and/or death stratified by delay from the index event and surgical technique (CEA/CAS).

RESULTS

Seventy-one studies with 232 952 symptomatic patients were included. Overall, 34 retrospective analyses of prospective databases, nine prospective, three RCT, three case control, and 22 retrospective studies were included. Compared with CEA, CAS was associated with higher 30 day stroke (OR 0.70; 95% CI 0.58 - 0.85) and mortality rates (OR 0.41; 95% CI 0.31 - 0.53) when performed ≤ 2 days of symptom onset. Patients undergoing CEA/CAS were analysed in different time frames (≤ 2 vs. 3 - 14 and ≤ 7 vs. 8 - 14 days). Expedited CEA (vs. 3 - 14 days) presented a sampled 30 day stroke rate of 1.4%; 95% CI 0.9 - 1.8 vs. 1.8%; 95% CI 1.8 - 2.0, with no statistically significant difference. Expedited CAS (vs. 3 - 14 days) was associated with no difference in stroke rate but statistically significantly higher mortality rate (OR 2.76; 95% CI 1.39 - 5.50).

CONCLUSION

At present, CEA is safer than transfemoral CAS within 2/7 days of symptom onset. Also, considering absolute rates, expedited CEA complies with the accepted thresholds in international guidelines. The ideal timing for performing CAS (when indicated against CEA) is not yet defined. Additional granular data and standard reporting of timing of intervention will facilitate future monitoring.

In-Hospital Outcomes of Urgent, Early, or Late Revascularization for Symptomatic Carotid Artery Stenosis

BACKGROUND AND PURPOSE

Advancements in carotid revascularization have produced promising outcomes in patients with symptomatic carotid artery stenosis. However, the optimal timing of revascularization procedures after symptomatic presentation remains unclear. The purpose of this study is to compare in-hospital outcomes of transcarotid artery revascularization (TCAR), transfemoral carotid stenting (TFCAS), or carotid endarterectomy (CEA) performed within different time intervals after most recent symptoms.

METHODS

This is a retrospective cohort study of United States patients in the vascular quality initiative. All carotid revascularizations performed for symptomatic carotid artery stenosis between September 2016 and November 2019 were included. Procedures were categorized as urgent (0-2 days after most recent symptom), early (3-14 days), or late (15-180 days). The primary outcome of interest was in-hospital stroke and death. Secondary outcomes include in-hospital stroke, death, and transient ischemic attacks. Multivariable logistic regression was used to compare outcomes.

RESULTS

A total of 18 643 revascularizations were included: 2006 (10.8%) urgent, 7423 (39.8%) early, and 9214 (49.42%) late. Patients with TFCAS had the highest rates of stroke/death at all timing cohorts (urgent: 4.0% CEA, 6.9% TFCAS, 6.5% TCAR, P=0.018; early: 2.5% CEA, 3.8% TFCAS, 2.9% TCAR, P=0.054; late: 1.6% CEA, 2.8% TFCAS, 2.3% TCAR, P=0.003). TFCAS also had increased odds of in-hospital stroke/death compared with CEA in all 3 groups (urgent adjusted odds ratio [aOR], 1.7 [95% CI, 1.0-2.9] P=0.03; early aOR, 1.6 [95% CI, 1.1-2.4] P=0.01; and late aOR, 1.9 [95% CI, 1.2-3.0] P=0.01). TCAR and CEA had comparable odds of in-hospital stroke/death in all 3 groups (urgent aOR, 1.9 [95% CI, 0.9-4], P=0.10), (early aOR, 1.1 [95% CI, 0.7-1.7], P=0.66), (late aOR, 1.5 [95% CI, 0.9-2.3], P=0.08).

CONCLUSIONS

CEA remains the safest method of revascularization within the urgent period. Among revascularization performed outside of the 48 hours, TCAR and CEA have comparable outcomes.

Association between high sensitivity C-reactive protein (hs-CRP) levels and the risk of major adverse cardiovascular events (MACE) and/or microembolic signals after carotid angioplasty and stenting

Background

To evaluate the association between pre/post-procedural high sensitive C-reactive protein (hs-CRP) level and hs-CRP difference, and the risk of major adverse cardiovascular events (MACE) or new diffusion-weighted MRI lesions after carotid angioplasty and stenting (CAS).

Methods

In this study, conducted in 2016 in Shiraz (Iran), patients who underwent diagnostic angiography and CAS were recruited. CAS was performed with distal embolic protection device on patients with both standard and high risk of endarterectomy. Pre/post-procedural hs-CRP, and hs-CRP difference were determined by immunoenzymometric assay method.

Results

A total of 50 patients with diagnostic angiography and 60 patients with CAS were enrolled. No death, myocardial infarction, ischemic or hemorrhagic stroke, and need to revascularization occurred during the 30-days of the post-procedural period. Accordingly, the statistical evaluation in associating MACE and hs-CRP levels was impossible. Angioplasty was associated with higher frequency of elevated post-procedural hs-CRP in comparison to angiography (P=0.003). The higher age, symptomatic lesions, negative history of hypertension, and hs-CRP difference had significant association with the presence of new DWI lesions in univariate analysis (all P<0.05). Angioplasty of left carotid bulb and post-procedural hs-CRP levels was very close to the level of significance (P=0.06). But only left sided lesions had positive association (P=0.037) and hypertension had negative association (P=0.037) in multivariate regression analysis. There were significant association between post-procedural hs-CRP level (P=0.02) and hs-CRP difference (P=0.003), and the number of new lesions; and the hs-CRP difference and the accumulated lesion surface area (P=0.009).

Conclusion

Post-procedural hs-CRP and hs-CRP difference may predict embolic complications of CAS.

Early carotid artery stenting after onset neurologic symptoms

Multicenter clinical trials level 1 evidence favors the application of carotid endarterectomy in symptomatic patients, especially the in the elderly cohort. Carotid artery stenting has been proposed as a possible early alternative in selected patients after onset of ipsilateral neurologic symptoms. It is well known that treatment of acute stroke is time-dependent in patients with acute ischemic stroke caused by high-grade stenosis of the internal carotid artery, but intensive medical treatment in conjunction with intervention to improve stroke severity and clinical outcomes has not been established. Two major clinical concerns exist: (1) the risk of hemorrhagic infarction after cerebral revascularization in the acute stage and (2) application of carotid stenting in the acute embolic stage, which may be associated with continued embolic risk after carotid artery stenting compared to carotid endarterectomy, which removes the symptomatic plaque. This review summarizes the indications and results of early carotid artery stenting after onset of neurologic symptoms, considering the new carotid stents and cerebral protection systems available for clinical use and enhanced stenting techniques.

Research Progress on the Risk Factors and Outcomes of Human Carotid Atherosclerotic Plaques

Objective:

Atherosclerosis is an inflammatory process that results in complex lesions or plaques that protrude into the arterial lumen. Carotid atherosclerotic plaque rupture, with distal atheromatous debris embolization, causes cerebrovascular events. This review aimed to explore research progress on the risk factors and outcomes of human carotid atherosclerotic plaques, and the molecular and cellular mechanisms of human carotid atherosclerotic plaque vulnerability for therapeutic intervention.

Data Sources:

We searched the PubMed database for recently published research articles up to June 2016, with the key words of “risk factors”, “outcomes”, “blood components”, “molecular mechanisms”, “cellular mechanisms”, and “human carotid atherosclerotic plaques”.

Study Selection:

The articles, regarding the latest developments related to the risk factors and outcomes, atherosclerotic plaque composition, blood components, and consequences of human carotid atherosclerotic plaques, and the molecular and cellular mechanisms of human carotid atherosclerotic plaque vulnerability for therapeutic intervention, were selected.

Results:

This review described the latest researches regarding the interactive effects of both traditional and novel risk factors for human carotid atherosclerotic plaques, novel insights into human carotid atherosclerotic plaque composition and blood components, and consequences of human carotid atherosclerotic plaque.

Conclusion:

Carotid plaque biology and serologic biomarkers of vulnerability can be used to predict the risk of cerebrovascular events. Furthermore, plaque composition, rather than lesion burden, seems to most predict rupture and subsequent thrombosis.

Usefulness of Early Stenting for Symptomatic Extracranial Carotid Stenosis

BACKGROUND

While carotid angioplasty and stenting (CAS) have become an established procedure, outcomes of early CAS for symptomatic extracranial carotid stenosis (SECS) remain poorly understood. The present study aimed at determining the effectiveness of early CAS in SECS.

METHODS

Herein, 224 SECS patients underwent elective CAS between January 2008 and June 2015. The study population was stratified based on the time from symptom onset to the procedure (early CAS group: within 14 days; delayed CAS group: later than 14 days). Subgroup analysis (chi-square test, Mantel-Haenszel chi-square test, and analysis of covariance) evaluated the demographics, incidence of periprocedural thromboembolic complications, cerebral hyperperfusion syndrome (CHS), intracranial bleeding, and treatment outcomes on the modified Rankin Scale (mRS).

RESULTS

Symptomatic thromboembolic complications and CHS were noted in 2.68% and 0.89% of patients, respectively. The initial National Institutes of Health Stroke Scale (NIHSS) score was significantly higher in patients who underwent early CAS than in those who underwent delayed CAS (2.50 ± 3.97 vs. 0.97 ± 2.08, P = 0.001). After adjusting for age, duration of preprocedural dual antiplatelet therapy, initial NIHSS score, and preprocedural NIHSS score, the groups did not differ significantly regarding the incidence of symptomatic thromboembolic complications (P = 0.195), incidence of CHS (P = 0.950), incidence of intracranial bleeding (P = 0.970), 30-day mRS score (P = 0.124), and mRS score at final follow-up (P = 0.132).

CONCLUSIONS

For SECS patients who cannot undergo early carotid endarterectomy, early CAS is effective and safe if selectively indicated considering disease severity. Early and delayed CAS provide comparable mRS scores, incidence of symptomatic thromboembolic complications, CHS, and intracranial bleeding.

Association of thrombelastographic parameters with post-stenting ischemic events

BACKGROUND AND PURPOSE

Thrombelastography (TEG) is widely used for the measurement of platelet function. However, few studies have investigated the TEG parameters in patients receiving extracranial or intracranial artery stenting for ischemic cerebrovascular disease. This study sought to describe the association of TEG parameters before the procedure with post-procedural ischemic events after extracranial or intracranial artery stenting.

METHODS

Patients in whom stenting was performed for extracranial or intracranial artery stenosis (70-99%) were recruited into the study. Blood samples were obtained for TEG to assess platelet function before stenting. The primary endpoint was ischemic stroke or transient ischemic attack in the territory of the stented artery.

RESULTS

A total of 218 patients were included in the study. During a mean follow-up period of 132 days (range 98-226 days), 18 (8.3%) primary endpoint events were recorded. Compared with patients without ischemic events, the ADP-induced platelet-fibrin clot strength (MA_ADP) was significantly higher (41.57±15.10 vs 33.50±13.86, p=0.020) and the ADP inhibition rate (ADP%) was significantly lower in patients with ischemic events (39.54±23.15 vs 55.29±24.43, p=0.009). Multivariate analysis identified MA_ADP and ADP% as significant independent predictors of subsequent ischemic events with HRs of 1.036 and 0.965, respectively. From receiver operating characteristic curve analysis, MA_ADP >49.95 mm had the best predictive value of ischemic events.

CONCLUSIONS

Our study suggests that TEG parameters MA_ADP and ADP% are associated with subsequent ischemic events in patients with extracranial or intracranial stents.

CLINICAL TRIAL NUMBER

NCT01925872.

Serum Levels of IL-1 β , IL-6, TGF- β , and MMP-9 in Patients Undergoing Carotid Artery Stenting and Regulation of MMP-9 in a New In Vitro Model of THP-1 Cells Activated by Stenting

Inflammation plays an important role in the pathophysiological process after carotid artery stenting (CAS). Monocyte is a significant source of inflammatory cytokines in vascular remodeling. Telmisartan could reduce inflammation. In our study, we first found that, after CAS, the serum IL-1β, IL-6, TGF-β, and MMP-9 levels were significantly increased, but only MMP-9 level was elevated no less than 3 months. Second, we established a new in vitro model, where THP-1 monocytes were treated with the supernatants of human umbilical vein endothelial cells (HUVECs) that were scratched by pipette tips, which mimics monocytes activated by mechanical injury of stenting. The treatment enhanced THP-1 cell adhesion, migration and invasion ability, and the phosphorylation of ERK1/2 and Elk-1 and MMP-9 expression were significantly increased. THP-1 cells pretreated with PD98095 (ERK1/2 inhibitor) attenuated the phosphorylation of ERK1/2 and Elk-1 and upregulation of MMP-9, while pretreatment with telmisartan merely decreased the phosphorylation of Elk-1 and MMP-9 expression. These results suggested that IL-1β, IL-6, TGF-β, and MMP-9 participate in the pathophysiological process after CAS. Our new in vitro model mimics monocytes activated by stenting. MMP-9 expression could be regulated through ERK1/2/Elk-1 pathway, and the protective effects of telmisartan after stenting are partly attributed to its MMP-9 inhibition effects via suppression of Elk-1.

Urgent Carotid Surgery: Is It Still out of Debate?

Patients with symptomatic tight carotid stenosis have an increased short-time risk of stroke and an increased long-term risk of ischaemic vascular events compared with the general population. The aim of this study is to assess the safety, efficacy, and limitations of urgent CEA or CAS, in patients with carotid stenosis greater than 70% and clinically characterized by recurrent TIA or brain damage following a stroke (<2.5 cm). This study involved 28 patients divided into two groups. Group A consisted of sixteen patients who had undergone CEA, and group B consisted of twelve patients who had undergone CAS. Primary endpoints were mortality, neurological morbidity (by NIHSS) and postoperative hemorrhagic cerebral conversion, at 30 days. Ten patients (62.5%) of group A experienced an improvement in their initial neurological deficit while in 4 cases (26%) the deficit remained stable. Two cases of neurologic mortality are presented. At 1 month, 9 patients (75%) of group B experienced an improvement in their initial neurological deficit while 3 patients (25%) had a neurological impairment. Urgent or deferred surgical or endovascular treatment have a satisfactory outcome considering the profile in very high-risk patient population. Otherwise in selected patients CEA seems to be preferred to CAS.

Nontraditional Risk Factors in Carotid Artery Disease

Carotid atherosclerosis (AS) is one of the main risk factors for ischemic stroke. Our aim is to evaluate the nontraditional biochemical markers in asymptomatic and symptomatic patients with carotid artery plaque. This study was conducted on 55 patients: 43 with symptomatic and 12 with asymptomatic carotid artery disease. Lipoprotein (a) (Lp(a)), homocysteine, adiponectin, nitric oxide (NO), and tumor necrosis factor α (TNF-α) levels were measured in the plasma. The mean of total cholesterol, triglyceride, and homocysteine levels was significantly elevated in the symptomatic group as compared with the asymptomatic group (P = .03). In the asymptomatic group, adiponectin and NO levels showed elevations as compared with the symptomatic group but this increase was not significant (P > .05). Lipoprotein (a) and TNF-α levels acted inversely with adiponectin and NO. There was an insignificant decline in Lp(a) and TNF-α levels in the asymptomatic group as compared with the symptomatic group (P > .05).

Outcome of Carotid Endarterectomy for Acute Neurological Deficit

We reviewed our experience with urgent carotid intervention in the setting of acute neurological deficits. Between June 1992 and August 2008, a total of 3145 carotid endarterectomies (CEA) were performed. Twenty-seven patients (<1.0%) were categorized as urgent. The mean age was 74.1 years (range 56-93 years) with 16 (60%) men, and 11 (40%) women, Symptoms included extremity weakness or paralysis (n = 13), amaurosis fugax (n = 6), speech difficulty (n = 2), and syncope, (n = 3). Three patients exhibited a combination of these symptoms. Three open thrombectomy were performed. Regional anesthesia was used in 13 patients (52%). Seventeen patients (67%), required shunt placement. At 30-days, 2 patient (7%) suffered a stroke, and 1 (4%) died. Urgent CEA can be performed safely. A stroke rate of 7% is acceptable in those who may otherwise suffer a dismal outcome without intervention.