Outcomes after Thrombectomy for Minor Stroke: A Meta-Analysis

Endovascular thrombectomy versus medical management for moderate-to-severe anterior cerebral artery occlusion stroke

BACKGROUND

There are no established patient selection criteria for endovascular thrombectomy (EVT) for anterior cerebral artery (ACA) stroke.

METHODS

This was a retrospective cohort study of the 2016-2020 National Inpatient Sample in the United States. Isolated ACA-occlusion stroke patients with moderate-to-severe stroke symptoms (NIH stroke scale [NIHSS] ≥ 6) were included. Primary outcome was hospital discharge to home with self-care. Secondary outcomes include in-hospital mortality and intracranial hemorrhage (ICH). Confounders were accounted for by multivariable logistic regression.

RESULTS

6685 patients were included; 335 received EVT. Compared to medical management (MM), EVT patients were younger (mean 67.2 versus 72.2 years; p = 0.014) and had higher NIHSS (mean 16.0 versus 12.5; p < 0.001). EVT was numerically but not statistically significantly associated with higher odds of home discharge compared to MM (aOR 2.26 [95%CI 0.99-5.17], p = 0.053). EVT was significantly associated with higher odds of home discharge among patients with NIHSS 10 or greater (aOR 3.35 [95%CI 1.06-10.58], p = 0.039), those who did not receive prior thrombolysis (aOR 3.96 [95%CI 1.53-10.23], p = 0.005), and those with embolic stroke etiology (aOR 4.03 [95%CI 1.21-13.47], p = 0.024). EVT was not significantly associated with higher rates of mortality (aOR 1.93 [95%CI 0.80-4.63], p = 0.14); however, it was significantly associated with higher rates of ICH (22.4% vs. 8.5%, p < 0.001).

CONCLUSION

EVT was associated with higher odds of favorable short-term outcomes for moderate-to-severe ACA-occlusion stroke in select patients. Future studies are needed to confirm the efficacy of EVT in terms of longer term neurological outcomes.

Thrombectomy vs. medical management for large vessel occlusion strokes with minimal symptoms

Patients with acute ischemic stroke (AIS) presenting mild symptoms with a low National Institutes of Health Stroke Scale (NIHSS) score ≤8 and also found to have an intracranial large vessel occlusion (LVO) undergo endovascular thrombolysis (ET) or medical management alone. The current study aimed to evaluate the safety and effectiveness of medical management vs. ET therapy among patients with mild AIS symptoms (NIHSS score ≤8) accompanied by LVO. The present meta-analysis included articles involving mild AIS, LVO, thrombectomy/ET and medical management alone published in full-text form (from 1980 to 2022). Collected variables included: First author name, covered study period, publication year, the total number of patients and age, number of males, presence of diabetes mellitus, hypertension, atrial fibrillation, prior ischemic stroke, location, NIHSS of admission, modified Rankin scale, bleeding, morbidity and mortality. After the initial search and applying all exclusion and inclusion criteria, eight articles were left in the final article pool. The total number of patients who underwent ET was 569, compared with 1097 with medical management for LVO strokes with minimal symptoms. The findings of the present meta-analysis study point out that ET management may be associated with a high risk of bleeding and mortality in patients with LVO presenting with mild symptoms (NIHSS score ≤8).

Outcomes in Patients with Minor Stroke: Diagnosis and Management in the Post-thrombectomy Era

In the era of mechanical thrombectomy and better preventative strategies, a higher number of patients are being discharged home from the hospital with the so-called minor strokes. This has significantly changed the landscape of stroke recovery. Unfortunately, while symptoms may be categorized as mild compared to individuals with higher NIH Stroke Scale scores, the physical, cognitive, and emotional sequelae can be disabling and result in failure to return to work and poor quality of life in a population with significant potential to recover fully. In this review, we discuss the current state of minor stroke, the most common pattern of resulting deficits, what is known about the underlying pathophysiology that leads to a relatively global pattern of impaired cognition following an infarct in any location, and special considerations for treatment based on this population's unique needs. Raising awareness of the current morbidity associated with minor stroke, the need for a uniform definition that allows for comparisons of individuals across studies, and further research focused on this population to optimize outcomes, has the potential to significantly improve recovery.

Regression analysis of bleeding factors and the correlation between FPE and NLR after mechanical thrombectomy for acute anterior circulation large vessel occlusion

Acute anterior circulation large vessel occlusion refers to a blockage in the blood flow of one of the major blood vessels in the anterior (front) part of the brain. Acute anterior circulation large vessel occlusion can lead to a range of symptoms, including sudden headache, difficulty speaking or understanding speech, weakness or numbness on one side of the body and loss of vision in one eye. According to relevant data, mechanical thrombectomy in the treatment of the large vessel recanalization rate can reach 70%. However, hemorrhage is one of the serious complications after mechanical thrombectomy, and it is the main factor leading to the deterioration of neurological function and death of patients after large blood vessels. Therefore, the risk factors of bleeding in patients were analyzed before surgery, and effective prevention during and after surgery had positive significance for patients undergoing mechanical thrombectomy. This study uses regression analysis to analyze the correlation between bleeding factors and FPE and NLR after mechanical thrombectomy for acute anterior circulation large vessel occlusion. We retrospectively analyzed 81 patients with acute anterior circulation large vessel occlusion who underwent mechanical embolization in our hospital from September 2019 to January 2022 and separated them into a bleeding group (46 patients) and a non-bleeding group (35 patients) based on the presence or absence of bleeding after surgery.

Assessing the Efficacy of Mechanical Thrombectomy in Patients with an NIHSS < 6 Presenting with Proximal Middle Cerebral Artery Vessel Occlusion as Compared to Best Medical Management

BACKGROUND AND PURPOSE

Minor acute ischemic stroke (AIS) patients-defined by an NIHSS score < 6-presenting with proximal middle cerebral artery large vessel occlusions (MCA-LVO) is a subgroup for which treatment is still debated. Although these patients present with minor symptoms initially, studies have shown that several patients afflicted with MCA-LVO in this subgroup experience cognitive and functional decline. Although mechanical thrombectomy (MT) is the standard of care for patients with an NIHSS score of 6 or higher, treatment in the minor stroke subgroup is still being explored. The purpose of this preliminary study is to report our center's experience in evaluating the potential benefit of mechanical thrombectomy (MT) in minor stroke patients when compared to medical management (MM).

METHODS

We performed a retrospective study with two comprehensive stroke centers within our hospital enterprise of consecutive patients presenting with minor AIS secondary to MCA-LVO (defined as M1 or proximal M2 segments of MCA). We subsequently evaluated patients who received MT versus those who received MM.

RESULTS

Between January 2017 and July 2021, we identified 46 AIS patients (11 treated with MT and 35 treated with MM) who presented with an NIHSS score < 6 secondary to MCA-LVO (47.8% 22/46 female, mean age 62.3 years, range 49-75 years). MT was associated with a significantly lower mRS at 90 days (median: 1.0 [IQR 0.0-2.0] versus 3.0 [IQR 1.0-4.0], p = <0.001), a favorable NIHSS shift (-4.0 [IQR -10.0--2.0] versus 0.0 [IQR -2.0-1.0], p = 0.002), favorable NIHSS shift dichotomization (5/11, 45.5% versus 3/35, 8.6%, p = 0.003) and favorable mRS dichotomization (7/11, 63.6% versus 14/35, 40.0%, p = 0.024).

CONCLUSIONS

In our center's preliminary experience, for AIS patients presenting with an NIHSS score < 6 secondary to MCA-LVO, MT may be associated with improved clinical outcomes when compared to MM only.

Cost-effectiveness of thrombectomy in patients with minor stroke and large vessel occlusion: effect of thrombus location on cost-effectiveness and outcomes

BACKGROUND

To evaluate the cost-effectiveness of endovascular thrombectomy (EVT) to treat large vessel occlusion (LVO) in patients with acute, minor stroke (National Institute of Health Stroke Scale (NIHSS) <6) and impact of occlusion site.

METHODS

A Markov decision-analytic model was constructed accounting for both costs and outcomes from a societal perspective. Two different management strategies were evaluated: EVT and medical management. Base case analysis was done for three different sites of occlusion: proximal M1, distal M1 and M2 occlusions. One-way, two-way and probabilistic sensitivity analyses were performed.

RESULTS

Base-case calculation showed EVT to be the dominant strategy in 65-year-old patients with proximal M1 occlusion and NIHSS <6, with lower cost (US$37 229 per patient) and higher effectiveness (1.47 quality-adjusted life years (QALYs)), equivalent to 537 days in perfect health or 603 days in modified Rankin score (mRS) 0-2 health state. EVT is the cost-effective strategy in 92.7% of iterations for patients with proximal M1 occlusion using a willingness-to-pay threshold of US$100 000/QALY. EVT was cost-effective if it had better outcomes in 2%-3% more patients than intravenous thrombolysis (IVT) in absolute numbers (base case difference -16%). EVT was cost-effective when the proportion of M2 occlusions was less than 37.1%.

CONCLUSIONS

EVT is cost-effective in patients with minor stroke and LVO in the long term (lifetime horizon), considering the poor outcomes and significant disability associated with non-reperfusion. Our study emphasizes the need for caution in interpreting previous observational studies which concluded similar results in EVT versus medical management in patients with minor stroke due to a high proportion of patients with M2 occlusions in the two strategies.

Endovascular Treatment for Minor Acute Ischemic Strokes With Large Vessel Occlusion

Background It remains uncertain whether patients with minor acute ischemic stroke with large vessel occlusion benefit from endovascular treatment (EVT). We aim to evaluate the outcomes of EVT in minor acute ischemic stroke with anterior circulation large vessel occlusion. Methods and Results Based on a nationwide prospective stroke registry, patients with minor acute ischemic stroke with anterior circulation large vessel occlusion within 24 hours of onset were divided into groups receiving standard medical treatment plus EVT or standard medical treatment alone. Primary outcome was excellent functional outcome defined as modified Rankin Scale score 0 to 1 at 90 days. In addition, a multivariable logistic regression model was used to analyze the effect of EVT guided by perfusion imaging. A total of 572 patients with median age 68 years (interquartile range=60-77) and median National Institutes of Health Stroke score 3 (interquartile range =2-4) were identified and 123 patients were treated with standard medical treatment plus EVT. EVT was not associated with excellent functional outcome (unadjusted odds ratio [OR], 0.771 [95% CI, 0.516-1.151]; adjusted OR, 0.793 [95% CI, 0.515-1.219]; P=0.290). However, therapy selection guided by perfusion imaging was a modifier of EVT effect on outcomes, as EVT was significantly associated with excellent functional outcome (60.0% versus 50.8%, unadjusted OR, 1.451 [95% CI, 0.643-3.272]; adjusted OR, 2.849 [95% CI, 1.006-8.067]; P=0.049) but not with symptomatic intracerebral hemorrhage in the imaging-guided group. Conclusions Although functional outcomes in minor acute ischemic stroke caused by anterior circulation large vessel occlusion were not improved from the routine use of EVT, our results suggested that EVT guided by perfusion imaging could be beneficial for those patients. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT04487340.

Minor stroke in large vessel occlusion: A matched analysis of patients from the German Stroke Registry-Endovascular Treatment (GSR-ET) and patients from the Safe Implementation of Treatments in Stroke-International Stroke Thrombolysis Register (SITS-ISTR)

BACKGROUND AND PURPOSE

Reperfusion treatment in patients presenting with large vessel occlusion (LVO) and minor neurological deficits is still a matter of debate. We aimed to compare minor stroke patients treated with endovascular thrombectomy (EVT) and intravenous thrombolysis (IVT) or IVT alone.

METHODS

Patients enrolled in the German Stroke Registry-Endovascular Treatment (GSR-ET) and the Safe Implementation of Treatments in Stroke-International Stroke Thrombolysis Registry (SITS-ISTR) between June 2015 and December 2019 were analyzed. Minor stroke was defined as National Institutes of Health Stroke Scale (NIHSS) score ≤5, and LVO as occlusion of the internal carotid, carotid-T, middle cerebral, basilar, vertebral or posterior cerebral arteries. GSR-ET and SITS-ISTR IVT-treated patients were matched in a 1:1 ratio using propensity-score (PS) matching. The primary outcome was good functional outcome at 3 months (modified Rankin Scale score 0-2).

RESULTS

A total of 272 GSR-ET patients treated with EVT and IVT (age 68.6 ± 14.0 years, 43.4% female, NIHSS score 4 [interquartile range 2-5]) were compared to 272 IVT-treated SITS-ISTR patients (age 69.4 ± 13.7, 43.4% female, NIHSS score 4 [2-5]). Good functional outcome was seen in 77.0% versus 82.9% (p = 0.119), mortality in 5.9% versus 7.9% (p = 0.413), and intracranial hemorrhage in 8.8% versus 12.5% (p = 0.308) of patients in the GSR-ET versus the SITS-ISTR IVT group, respectively. In a second PS-matched analysis, 624 GSR-ET patients (IVT rate 56.7%) and 624 SITS-ISTR patients (IVT rate 100%), good outcome was more often observed in the SITS-ISTR patients (68.2% vs. 80.9%; p < 0.001), and IVT independently predicted good outcome (odds ratio 2.16, 95% confidence interval 1.43-3.28).

CONCLUSIONS

Our study suggests similar effectiveness of IVT alone compared to EVT with or without IVT in minor stroke patients. There is an urgent need for randomized controlled trials on this topic.