Clinical Outcomes of Extracranial Carotid Artery-Related Stroke Eligible for Mechanical Reperfusion on Top of Per-Guidelines Thrombolytic Therapy: Analysis from a 6-Month Consecutive Patient Sample in 2 Centers.

BACKGROUND Systemic intravenous thrombolysis and mechanical thrombectomy (MT) are guideline-recommended reperfusion therapies in large-vessel-occlusion ischemic stroke. However, for acute ischemic stroke of extracranial carotid artery origin (AIS-CA) there have been no specific trials, resulting in a data gap. MATERIAL AND METHODS We evaluated referral/treatment pathways, serial imaging, and neurologic 90-day outcomes in consecutive patients, presenting in a real-life series in 2 stroke centers over a period of 6 months, with AIS-CA eligible for emergency mechanical reperfusion (EMR) on top of thrombolysis as per guideline criteria. RESULTS Of 30 EMR-eligible patients (33.3% in-window for thrombolysis and thrombolysed, 73.3% male, age 39-87 years, median Alberta Stroke Program Early Computed Tomography Score (ASPECTS) 10, pre-stroke mRS 0-1 in all, tandem lesions 26.7%), 20 (66.7%) were EMR-referred (60% - endovascular, 6.7% - surgery referrals). Only 40% received EMR, nearly exclusively in stroke centers with carotid artery stenting (CAS) expertise (100% eligible patient acceptance rate, 100% treatment delivery involving CAS±MT with culprit lesion sequestration using micronet-covered stents). The emergency surgery rate was 0%. Baseline clinical and imaging characteristics did not differ between EMR-treated and EMR-untreated patients. Ninety-day neurologic status was profoundly better in EMR-treated patients: mRS 0-2 (91.7% vs 0%; P<0.001); mRS 3-5 (8.3% vs 88.9%; P<0.001), mRS 6 (0% vs 11.1%; P<0.001). CONCLUSIONS In a real-life AIS-CA setting, the referral rate of EMR-eligible patients for EMR was low, and the treatment rate was even lower. AIS-CA revascularization was delivered predominantly in stroke thrombectomy-capable cardioangiology centers, resulting in overwhelmingly superior patient outcome. Large vessel occlusion stroke referral and management pathways should involve centers with proximal-protected CAS expertise. AIS-CA, irrespective of any thrombolysis administration, is a hyperacute cerebral emergency and EMR-eligible patients should be immediately referred for mechanical reperfusion.

A multi-center study of the MicroNET-covered stent in consecutive patients with acute carotid-related stroke: SAFEGUARD-STROKE.

Introduction: Acute carotid-related stroke (CRS), with its large thrombo-embolic load and large volume of affected brain tissue, poses significant management challenges. First generation (single-layer) carotid stents fail to insulate the athero-thrombotic material; thus they are often non-optimized (increasing thrombosis risk), yet their use is associated with a significant (20-30%) risk of new cerebral embolism. Aim: To evaluate, in a multi-center multi-specialty investigator-initiated study, outcomes of the MicroNET-covered (cell area ≈ 0.02-0.03 mm2) carotid stent (CGuard, InspireMD) in consecutive CRS patients eligible for emergency recanalization. Treatment, other than study device use, was according to center/operator routine. Material and methods: Seventy-five patients (age 40-89 years, 26.7% women) were enrolled in 7 interventional stroke centers. Results: The median Alberta Stroke Program Early CT Score (ASPECTS) was 9 (6-10). Study stent use was 100% (no other stent types implanted); retrograde strategy predominated (69.2%) in tandem lesions. Technical success was 100%. Post-dilatation balloon diameter was 4.0 to 8.0 mm. 89% of patients achieved final modified Thrombolysis in Cerebral Infarction (mTICI) 2b-c/3. Glycoprotein IIb/IIIa inhibitor use as intraarterial (IA) bolus + intravenous (IV) infusion was an independent predictor of symptomatic intracranial hemorrhage (OR = 13.9, 95% CI: 5.1-84.5, p < 0.001). The mortality rate was 9.4% in-hospital and 12.2% at 90 days. Ninety-day mRS0-2 was 74.3%, mRS3-5 13.5%; stent patency was 93.2%. Heparin-limited-to-flush predicted patency loss on univariate (OR = 14.3, 95% CI: 1.5-53.1, p < 0.007) but not on multivariate analysis. Small-diameter balloon/absent post-dilatation was an independent predictor of stent patency loss (OR = 15.2, 95% CI: 5.7-73.2, p < 0.001). Conclusions: This largest to-date study of the MicroNET-covered stent in consecutive CRS patients demonstrated a high acute angiographic success rate, high 90-day patency and favorable clinical outcomes despite variability in procedural strategies and pharmacotherapy (SAFEGUARD-STROKE NCT05195658).

Carotid artery revascularization using second generation stents versus surgery: a meta-analysis of clinical outcomes.

INTRODUCTION: Meta-analyses and emerging randomized data indicate that second-generation ('mesh') carotid stents (SGS) may improve outcomes versus conventional (single-layer) stents but clinically-relevant differences in individual SGS-type performance have been identified. No comparisons exist for SGS versus carotid endarterectomy (CEA). EVIDENCE ACQUISITION: Thirty-day death (D), stroke (S), myocardial infarction (M), and 12-month ipsilateral stroke and restenosis in SGS studies were meta-analyzed (random effect model) against CEA outcomes. Eligible studies were identified through PubMed/EMBASE/COCHRANE. Forest plots were formed for absolute adverse evet risk in individual studies and for relative outcomes with each SGS deign versus contemporary CEA outcomes as reference. Meta-regression was performed to identify potential modifiers of treatment modality effect. EVIDENCE SYNTHESIS: Data were extracted from 103,642 patients in 25 studies (14 SGS-treated, 41% symptomatic; nine randomized controlled trial (RCT)-CEA-treated, 37% symptomatic; and two Vascular Quality Initiative (VQI)-CEA-treated, 23% symptomatic). Casper/Roadsaver and CGuard significantly reduced DSM versus RCT-CEA (-2.70% and -2.95%, P<0.001 for both) and versus VQI-CEA (-1.11% and -1.36%, P<0.001 for both). Gore stent 30-day DSM was similar to RCT-CEA (P=0.581) but increased against VQI-CEA (+2.38%, P=0.033). At 12 months, Casper/Roadsaver ipsilateral stroke rate was lower than RCT-CEA (-0.75%, P=0.026) and similar to VQI-CEA (P=0.584). Restenosis with Casper/Roadsaver was +4.18% vs. RCT-CEA and +4.83% vs. VQI-CEA (P=0.005, P<0.001). CGuard 12-month ipsilateral stroke rate was similar to VQI-CEA (P=0.850) and reduced versus RCT-CEA (-0.63%, P=0.030); restenosis was reduced respectively by -0.26% and -0.63% (P=0.033, P<0.001). Twelve-month Gore stent outcomes were overall inferior to surgery. CONCLUSIONS: Meta-analytic integration of available clinical data indicates: 1) reduction in stroke but increased restenosis rate with Casper/Roadsaver, and 2) reduction in both stroke and restenosis with CGuard MicroNET-covered stent against contemporary CEA outcomes at 30 days and 12 months used as a reference. This may inform clinical practice in anticipation of large-scale randomized trials powered for low clinical event rates (PROSPERO-CRD42022339789).

Misclassification of carotid stenosis severity with area stenosis-based evaluation by computed tomography angiography: impact on erroneous indication to revascularization or patient (lesion) migration to a higher guideline recommendation class as per ESC/ESVS/ESO/SVS and CMS-FDA thresholds.

Intoduction: Despite a growing understanding of the role played by plaque morphology, the degree of carotid lumen reduction remains the principle parameter in decisions on revascularization in symptomatic and asymptomatic patients. Computed tomography angiography (CTA) is a widely used guideline-approved imaging modality, with "percent stenosis" commonly calculated as %area reduction (area stenosis - AS). Aim: We evaluated the impact of the non-linear relationship between diameter stenosis (DS) and AS (area = π • (diameter/2)2, so that in concentric lesions 51%AS is 30%DS and 75%AS is 50%DS) on stenosis severity misclassification using calculation of area reduction. Material and methods: CTA and catheter quantitative angiography (cQA) were performed in 300 consecutive patients referred to a tertiary vascular centre for potential carotid revascularization (age: 47-83 years, 33.7% symptomatic, 36% female; referral stenosis of ≥ "50%"). CTA-AS was determined by agreement of 2 experienced radiologists; cQA-DS (pivotal trials standard reference, NASCET method) was calculated by agreement of 2 corelab analysts. Results: For symptomatic lesion thresholds, CTA-AS-based calculation reclassified 76% of "< 50%" cQA-DS measurements to the "50-69%" group, and 58% of "50-69%" measurements to the "≥ 70%" group. For asymptomatic lesion thresholds, 78% of "< 60%" cQA-DS measurements were reclassified to the "60-79%" group, whereas 42% of "60-79%" cQA measurements crossed to the "≥ 80%" class. Overall, employing CTA-AS instead of cQA-DS enlarged the "60-79%" and "≥ 80%" lesion severity classes 1.6- and 5.8-fold, respectively, whereas the "≥ 70%" class increased 4.15-fold. Conclusions: Replacing the pivotal carotid trials reference standard cQA-DS "%stenosis" measurement with CTA-AS-based "%stenosis" results in a large-scale lesion/patient erroneous gain of an "indication" to revascularization or migration to a higher revascularization indication class. In consequence, unnecessary carotid procedures may be performed in the absence of cQA verification. Until guidelines rectify the "%stenosis" measurement methods with different guideline-approved imaging modalities (and, where needed, re-adjust decision thresholds), CTA-AS measurement should not be used as a basis for carotid revascularization.