Abstract 1122‐000227: Stenting Versus Medical Treatment for Chronic Internal Carotid Artery Occlusions: A Systematic Review and Meta‐analysis

Introduction : Chronic internal carotid occlusion is responsible for 10–15% ischemic strokes or transit ischemic attacks (TIA). Subsequent ipsilateral ischemic stroke rate is 5.9% per year. However, this risk can increase up to 23% in two years in a subgroup of patients with poor collaterals regardless of medical therapy with antiplatelet or anticoagulant agents. Prevention of subsequent stroke in patients with carotid artery occlusion remains a difficult challenge. Carotid artery stenting (CAS) has recently been considered in its management. However, there is ambiguity on its safety. We aim to evaluate the safety and feasibility of CAS and compared it with medical management. Methods : We performed a systematic review and meta‐analysis to compare long‐term outcome (stroke recurrence) of current carotid occlusion treatments (CAS vs medical therapy). Two independent reviewers performed the screening, data extraction, and quality assessment. A random effects model was used for analysis. Results : A total of 5720 studies were screened. Of these, 11 studies were included in our systematic review and meta‐analysis of proportions. The CAS group has lower proportions of recurrent strokes (5% vs 30%,) after 30 days than medical therapy alone. Additionally, the proportion of periprocedural intracranial hemorrhage was 4.4% (95% CI 2.5 to 6.8) in the CAS group. Conclusions : CAS of the chronically occluded cervical ICA seems to be a safe procedure with lower rates of recurrent stroke in clinical follow up. Future randomized studies are warranted to guide the optimal management of this complex disease.

Comparison the effects of carotid endarterectomy with carotid artery stenting for contralateral carotid occlusion

Background There have been inconsistent results regarding the use of carotid artery endarterectomy (CEA) versus carotid artery stenting (CAS) for contralateral carotid occlusion (CCO). This study aimed to determine the optimal revascularization technique for patients with CCO. Methods We systematically searched the PubMed, Embase, and Cochrane Library databases to identify eligible studies published from inception to January 2, 2021. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to calculate pooled effect estimates using a random-effects model. Sensitivity, subgroup, and publication bias analyses were also performed. Results Six studies involving 6,953 patients were selected for inclusion in this meta-analysis. Our results showed that while CEA was not associated with an increased risk of stroke compared to CAS (OR: 1.07; 95% CI: 0.75–1.51; P = 0.713), CEA was associated with a reduced risk of death compared to CAS (OR: 0.45; 95% CI: 0.29–0.70; P < 0.001). Furthermore, there were no significant differences between CEA and CAS for the risks of myocardial infarction (OR: 1.38; 95% CI: 0.73–2.62; P = 0.319) or major adverse cardiovascular events (OR: 1.03; 95% CI: 0.56–1.88; P = 0.926). Finally, the risk of myocardial infarction for CEA versus CAS was affected by disease status, while the risk of major adverse cardiovascular events was affected by the proportions of patients with male gender, coronary artery disease, and current or prior smoking. Conclusion This study found that CEA and CAS resulted in similar outcomes for patients with CCO, while the risk of death was reduced in patients treated with CEA. Further high-level evidence should be collected to verify the results of this study.

Temporary application of lower body positive pressure improves intracranial velocities in symptomatic acute carotid occlusion or tight stenosis: A pilot study

Background Patients with isolated cervical carotid artery occlusion not eligible to recanalization therapies but with compromised intracranial hemodynamics may be at risk of further clinical events. Apart from lying flat until spontaneous recanalization or adjustment of the collateral circulation hopefully occurs, no specific treatment is currently implemented. Improving collateral flow is an attractive option in this setting. Lower body positive pressure (LBPP) is known to result in rapid venous blood shift from the lower to the upper body part, in turn improving cardiac preload and output, and is routinely used in acute hemorrhagic shock. We report here cerebral blood flow velocities measured during LBPP in this patient population. Methods This is a retrospective analysis of the clinical, physiological, and transcranial Doppler monitoring data collected during and 15 min after LBPP in 21 consecutive patients (10 females, median age: 54 years) with recently symptomatic isolated carotid occlusion/tight stenosis (unilateral in 18) mostly due to atherosclerosis or dissection. LBPP was applied for 90 min at a median 5 days after symptom onset. Results At baseline, middle-cerebral artery velocities were markedly lower on the symptomatic, as compared to asymptomatic, side. LBPP significantly improved blood flow velocities in both the symptomatic and asymptomatic middle-cerebral artery as well as the basilar artery, which persisted 15 min after discontinuing the procedure. LBPP also resulted in mild but significant increases in mean arterial blood pressure. Conclusions LBPP improved intracranial hemodynamics downstream recently symptomatic carotid occlusion/tight stenosis as well as in the contralateral and posterior circulations, which persisted after LBPP deflation. Randomized trials should determine if this easy-to-use, noninvasive, nonpharmacologic approach has long-lasting benefits on the intracranial circulation and improves functional outcome.