Management of internal carotid artery near-occlusion: the need for updated evidence

Carotid Near-Occlusion: Surgical or Conservative Management? Retrospective Multicenter Study

BACKGROUND

Carotid near-occlusion (CNO) represents an anatomical-functional condition characterized by severe (more than 90%) internal carotid artery stenosis which can lead to a distal lumen diameter greater or less than 2 mm. CNO can be divided into a less severe subgroup (without lumen full collapse: diameter >2 mm) and a more severe subgroup (with lumen full collapse: diameter <2 mm). The decision for revascularization is still highly debated in Literature. The aim of the present multicenter retrospective study is to analyze the incidence of perioperative (30 days) and follow-up complications in 2 groups of patients with or without distal internal carotid lumen full collapse.

METHODS

Between January 2011 and March 2023, in 5 Vascular Surgery Units, 67 patients (49 male, 73% and 18 females, 27%) with CNO underwent carotid endarterectomy: 28 (41.7%) with lumen diameter <2 mm and 39 (58.3%) with diameter >2 mm. 19 patients were symptomatic and 48 asymptomatic. The outcomes considered for comparative analysis were: perioperative neurological and cardiac complications, carotid restenosis or occlusion at follow-up. Both groups were homogeneous in terms of risk factors, morphological features and pharmacological treatments.

RESULTS

In the group with lumen <2 mm, 3 perioperative major events (10.7%) occurred (1 ischemic stroke, 1 hemorrhagic stroke, 1 myocardial infarction) and 2 (7.1%) at follow-up (average 11 ± 14.5 months; 1 asymptomatic carotid occlusion, 1 hemodynamic restenosis treated with stenting). No event was recorded in the group with lumen >2 mm.

CONCLUSIONS

According to our results CNO patients show different complication risk according to the presence or not of distal lumen collapse. The later seems to play a significant role in perioperative and follow-up complication rate. These results therefore support a surgical treatment only in patients with CNO without lumen full collapse.

Cartoid Near Occlusion: Time to Re-think Endarectomy?

OBJECTIVES

Carotid near occlusion (CNO) treatment is still controversial. In the discussion of surgical revascularization of these patients, periprocedural complications and technical failure should be considered in addition to the long-term results. We examined the efficacy and safety of surgical treatment in CNO and non-CNO patients undergoing carotid endarterectomy (CEA).

METHODS

Data from 152 patients (118 male and 34 female) who underwent isolated CEA between January 2018 and June 2020 without critical contralateral lesions were retrospectively analyzed. Patients were divided into 2 groups: CNO (n = 52) and non-CNO (n = 100). The groups were compared regarding postoperative transient ischemic attack (TIA), ipsilateral ischemic stroke, and mortality.

RESULTS

The success rate of the procedure was 100% in the CNO group and 99% in the Non-CNO group. In the Non-CNO group, 1 patient had ipsilateral ischemic stroke on postoperative day 0, and this patient was treated with carotid artery stenting. While the number of patients who died in the non-CNO group was 3 (3%) overall, the exitus rate was 1 (1.9%) in the CNO group (P >.05). In the CNO group, retinal TIA was observed in 1 patient (1.9%), ischemic stroke in 2 patients (3.8%), and TIA in 1 patient (1.9%). In the non-CNO group; Retinal TIA was observed in 1 patient (1.0%), ischemic stroke in 2 patients (2.0%), and TIA in 2 patients (2.0%). There was no statistically significant difference between the groups in terms of postoperative neurologic complications and primary endpoints at 12-month follow-up (P >.05).

CONCLUSIONS

Carotid endarterectomy is a safe, feasible, and advantageous procedure in selected CNO patients, as in non-CNO carotid artery patients. Therefore, we recommend a surgical approach to prevent neurological events in CNO patients.

Effect of Treatment Choice on Short-Term and Long-Term Outcomes for Carotid Near-Occlusion: A Meta-Analysis

OBJECTIVE

Current guidelines recommend best medical treatment (BMT) over revascularization for carotid near-occlusion (CNO); however, it remains unclear whether BMT, carotid artery stenting (CAS), or carotid endarterectomy (CEA) is the optimal treatment strategy. The present meta-analysis aimed to compare outcomes among patients with CNO receiving BMT, CAS, or CEA.

METHODS

PubMed, Web of Science, Scopus, and Embase were searched. English studies with ≥1 month follow-up, that used established CNO diagnostic guidelines, that provided outcomes by treatment, and in which 95% confidence intervals (CIs) were calculable were included. Studies on acute ischemic stroke (AIS) requiring emergent reperfusion therapy, nonatherosclerotic lesions, nonprimary research articles, non-English, and nonhuman studies were excluded. Outcomes were mortality, AIS, transient ischemic attack, myocardial infarction within and beyond 30 days, and restenosis. A generalized linear mixed model, subgroup analysis, and meta-regression were used to compare outcomes.

RESULTS

Thirty-eight studies were included. Pooled rates for AIS beyond 30 days were 9.90% (95% CI, 4.31%-21.16%), 0.79% (95% CI, 0.24%-2.53%), and 0.80% (95% CI, 0.15%-4.07%) for BMT, CAS, and CEA, respectively. Subgroup analysis was statistically significant (P < 0.001). Meta-regression showed lower incidence favoring procedural intervention (CAS vs. BMT, P = 0.001; CEA vs. BMT, P = 0.003). Subgroup analysis for mortality beyond 30 days was also significant (P = 0.016) but meta-regression did not favor one treatment over another. Other outcomes were not statistically significant.

CONCLUSIONS

Revascularization for CNO may decrease long-term stroke rates. Given that current guidelines are based on randomized controlled trials from the 1990s, updated randomized trials are warranted to determine the optimal treatment for CNO.

Endarterectomy, Stenting, or Medical Treatment for Symptomatic Carotid Near-Occlusion: Results from CAOS, a Multicenter Registry Study

BACKGROUND AND PURPOSE

The treatment of symptomatic carotid near-occlusion is controversial. Our aim was to analyze the results of carotid endarterectomy and carotid artery stent placement in patients with symptomatic carotid near-occlusion and to identify factors related to technical failure, periprocedural complications, and restenosis.

MATERIALS AND METHODS

We conducted a multicenter, prospective nonrandomized study. Patients with angiography-confirmed carotid near-occlusion were included. We assessed the revascularization rate and periprocedural stroke or death. Twenty-four-month clinical and carotid imaging follow-up was performed, and rates of carotid restenosis or occlusion, ipsilateral stroke, and mortality were analyzed. Carotid artery stent placement, carotid endarterectomy, and medical treatment were compared.

RESULTS

One hundred forty-one patients were included. Forty-four carotid artery stent placement and 23 carotid endarterectomy procedures were performed within 6 months after the event. Complete revascularization was achieved in 83.6%, 81.8% in the carotid artery stent placement group and 87% with carotid endarterectomy (P = .360). Periprocedural stroke or death occurred in 6% (carotid artery stent placement = 2.3%; carotid endarterectomy = 13%; P = .077) and was not related to revascularization failure. The carotid restenosis or occlusion rate was 8.3% (5% restenosis, 3.3% occlusion); with carotid artery stent placement it was 10.5%; and with carotid endarterectomy it was 4.5% (P = .419). The 24-month cumulative rate of ipsilateral stroke was 4.8% in the carotid artery stent placement group, 17.4% for carotid endarterectomy, and 13.1% for medical treatment (P = .223). Mortality was 12%, 4.5%, and 5.6%, respectively (P = .422). Revascularization failure and restenosis occurred more frequently in patients with full collapse compared with patients without full collapse (33.3% versus 5.6%, P = .009; 21.4% versus 2.9%, P = .032, respectively).

CONCLUSIONS

Carotid artery stent placement and carotid endarterectomy are associated with high rates of failure and periprocedural stroke. Carotid near-occlusion with full collapse appears to be associated with an increased risk of technical failure and restenosis. Carotid near-occlusion revascularization does not seem to reduce the risk of stroke at follow-up compared with medical treatment.

Carotid Endarterectomy for the Treatment of Carotid Near-Occlusion With Recurrent Symptoms

Objective

Report our preliminary experience of carotid endarterectomy (CEA) for the treatment of carotid near-occlusion (CNO) with recurrent symptoms.

Materials and Methods

Retrospectively analyze the demographics, treatment detail, and outcomes data of 122 patients with CNO from 2014 to 2020. According to whether distal full collapse exists, patients were classified into the full collapse group and the non-full collapse group. The incidence of death, myocardial infarction, stroke, and other variables were compared between the two groups.

Results

A total of 122 patients with CNO and recurrent symptoms were enrolled. The demographics were comparable between the two groups. Thirty-day incidence of primary endpoints was 1.85% in the full collapse group and 4.41% in the non-full collapse group. Twelve-month incidence of primary endpoints was 7.41% in the full collapse group and 4.41% in the non-full collapse group. One re-stenosis occurred in the non-full collapse group 8 months after CEA.

Conclusion

For patients with CNO with recurrent symptoms, CEA is not worse than the results described in historical control groups, despite whether distal full collapse exists. The shunt is important to avoid intraoperative hypoperfusion and postoperative hyperperfusion. The long-term results should be further evaluated.

The periprocedural and 30-day outcomes of carotid stenting in patients with carotid artery near-occlusion

The safety of endovascular revascularization in patients with carotid artery near occlusion (CANO) is unknown. We aimed to evaluate the peri-procedural risk in CANO patients receiving carotid artery stenting (CAS). A prospective data base with retrospective review was performed to identify patients who underwent CAS with CANO from July 2006 to July 2020, and had at least 1-month clinical follow-up data. The primary endpoints were stroke, hyperperfusion syndrome, and death within 30 days after CAS. A total of 198 patients with carotid artery stenosis were enrolled including 92 patients with CANO and 106 age and sex-matched patients with 70–99% conventional carotid stenosis. Full distal carotid collapse was found in 45 CANO patients (45/92, 49%). The technical success rate was 100%. The CANO patients had significantly longer lesion lengths compared with those of the non-CANO group. The incidence of hyperperfusion syndrome was comparable (CANO: 2.2%, non-CANO: 0.9%, P = 0.598). The risks of ischemic stroke and death within 30 days were 1.1% and 0% in the CANO group; and 1.9% and 0.9%, in the non-CANO group, respectively, without statistical difference. In conclusion, CAS is safe for patients with CANO, with a similar low 30-day peri-procedural event rate comparable to those of non-CANO.

Near-Occlusion is a Common Variant of Carotid Stenosis: Study and Systematic Review

BACKGROUND

Symptomatic carotid near-occlusion is often described as rare. Recent studies have shown that near-occlusions are overlooked, especially near-occlusion without full collapse (with a small but normal-appearing distal internal carotid artery).

OBJECTIVE

To assess the prevalence of near-occlusion among symptomatic ≥50% carotid stenosis, incidence of symptomatic near-occlusion, and review the literature.

METHODS

Prospective controlled single-center cross-sectional study. Consecutive cases with symptomatic ≥50% carotid stenosis were examined with computed tomography angiography (CTA). The CTAs were assessed for near-occlusion by two observers. A systematic literature review was performed with emphasis on how study design affects prevalence estimate.

RESULTS

Totally, 186 patients with symptomatic ≥50% carotid stenosis were included, 34% (n = 63, 95% CI 27, 41) had near-occlusion. The incidence of symptomatic near-occlusion was 3.4 (95% CI 2.5, 4.2) per 100,000 person-years. Inter-rater κ was 0.71. The average prevalence of near-occlusion among symptomatic ≥50% carotid stenosis was higher in studies with good design (30%, range 27%-34%) than studies without good design (9%, range 2%-10%).

CONCLUSIONS

Near-occlusion is common variant of symptomatic ≥50% carotid stenosis, both in the current study and in all previous studies of good design. Studies that suggest that near-occlusion is rare have had methodological issues.