Mechanical Thrombectomy Outcomes in COVID-19 Patients With Acute Ischemic Stroke: A Narrative Review

Outcomes in patients with large vessel occlusion strokes undergoing mechanical thrombectomy with concurrent COVID-19: a nationwide retrospective analysis

BACKGROUND

Preliminary studies show that patients with large vessel occlusion (LVO) acute ischemic strokes have worse outcomes with concurrent COVID-19 infection. We investigated the outcomes for patients with LVO strokes undergoing mechanical thrombectomy (MT) with concurrent COVID-19 infection.

METHODS

The National Inpatient Database (NIS) was used for our analysis. Patients in the year 2020 with an ICD-10 diagnosis code for acute ischemic stroke and procedural code for MT were included with and without COVID-19. Odds ratios (OR) were calculated using a logistic regression model with age, sex, stroke location, Elixhauser comorbidity score, and other patient variables deemed clinically relevant as covariates.

RESULTS

Patients in the COVID-19 group were younger (64.3±14.4 vs 69.4±14.5 years, P<0.001), had a higher rate of inpatient mortality (22.4% vs 10.1%, P<0.001), and a longer length of stay (10 vs 6 days, P<0.001). Patients with COVID-19 had higher odds of death (OR 2.78, 95% CI 2.11 to 3.65) and lower odds of a routine discharge (OR 0.65, 95% CI 0.48 to 0.89). There was no difference in the odds of subsequent stroke and cerebral hemorrhage, but patients with COVID-19 had statistically significantly higher odds of respiratory failure, pulmonary embolism, deep vein thrombosis, myocardial infarction, acute kidney injury, and sepsis.

CONCLUSIONS

Patients with LVOs undergoing MT within the 2020 NIS database had worse outcomes when co-diagnosed with COVID-19, likely due to non-neurological manifestations of COVID-19.

The effect of COVID-19 on treatment and outcomes following ischemic stroke: A national assessment

INTRODUCTION

COVID-19 has had innumerable impacts on the healthcare system, both by worsening patient illness and impeding effective and efficient care. Further, COVID-19 has been tied to increased rates of ischemic stroke, particularly among young patients. We utilized a national database to assess associations of COVID-19 with thrombectomy rates, mortality, and discharge disposition among stroke patients.

METHODS

Patients were identified from the National Inpatient Sample (NIS, 2020). Inclusion criteria selected for adult ischemic stroke patients; those with venous thrombosis or unspecified cerebral infarction were excluded. Patients were stratified by presence or absence of COVID-19 diagnosis. Outcome variables included mechanical thrombectomy, in-hospital mortality, and discharge disposition. Additional patient demographics, hospital characteristics, and disease severity metrics were collected. Statistical analysis was performed via multivariable logistic regression and log-binary regression.

RESULTS

54,368 patients were included in the study; 2116 (3.89%) were diagnosed with COVID-19. COVID-19 was associated with lower rates of mechanical thrombectomy (OR 0.94, p < 0.0001), higher rates of in-hospital mortality (OR 1.14, p < 0.0001), and unfavorable discharge disposition (OR 1.08, p < 0.0001), even when controlling for illness severity. Other relationships, such as a male predominance among stroke patients with COVID-19, were also identified.

CONCLUSION

This study identified a relationship between COVID-19 diagnosis and worse outcomes for each metric assessed, including mechanical thrombectomy rates, in-hospital mortality, and discharge disposition. Several factors might underly this, ranging from systemic/multisystem inflammation and worsened disease severity to logistical barriers to treatment caused by COVID-19. Further research is needed to determine causality of these findings.

Endotheliitis and cytokine storm as a mechanism of clot formation in COVID-19 ischemic stroke patients: A histopathologic study of retrieved clots

BACKGROUND

Studies during the COVID-19 pandemic have demonstrated an association between COVID-19 virus infection and the development of acute ischemic stroke, particularly large vessel occlusion (LVO). Studying the characteristics and immunohistochemistry of retrieved stroke emboli during mechanical thrombectomy for LVO may offer insights into the pathogenesis of LVO in COVID-19 patients. We examined retrieved COVID-19 emboli from the STRIP, EXCELLENT, and RESTORE registries and compared their characteristics to a control group.

METHODS

We identified COVID-positive LVO patients from the STRIP, RESTORE, and EXCELLENT studies who underwent mechanical thrombectomy. These patients were matched to a control group controlling for stroke etiology based on Trial of Org 10172 in Acute Stroke Treatment criteria. All clots were stained with Martius Scarlet Blue (MSB) along with immunohistochemistry for interleukin-6 (IL-6), C-reactive protein (CRP), von Willebrand factor (vWF), CD66b, fibrinogen, and citrullinated Histone H3. Clot composition was compared between groups.

RESULTS

Nineteen COVID-19-positive patients and 38 controls were included. COVID-19-positive patients had a significantly higher percentage of CRP and vWF. There was no difference in IL-6, fibrin, CD66b, or citrullinated Histone H3 between groups. Based on MSB staining, there was no statistically significant difference regarding the percentage of red blood cells, white blood cells, fibrin, and platelets.

CONCLUSIONS

Our study found higher concentrations of CRP and vWF in retrieved clots of COVID-19-positive stroke patients compared to COVID-19-negative controls. These findings support the potential role of systemic inflammation as indicated by elevated CRP and endothelial injury as indicated by elevated vWF as precipitating factors in thrombus development in these patients.

Pathophysiology, diagnosis, and management of neuroinflammation in covid-19

Although neurological complications of SARS-CoV-2 infection are relatively rare, their potential long term morbidity and mortality have a significant impact, given the large numbers of infected patients. Covid-19 is now in the differential diagnosis of a number of common neurological syndromes including encephalopathy, encephalitis, acute demyelinating encephalomyelitis, stroke, and Guillain-Barré syndrome. Physicians should be aware of the pathophysiology underlying these presentations to diagnose and treat patients rapidly and appropriately. Although good evidence has been found for neurovirulence, the neuroinvasive and neurotropic potential of SARS-CoV-2 is limited. The pathophysiology of most complications is immune mediated and vascular, or both. A significant proportion of patients have developed long covid, which can include neuropsychiatric presentations. The mechanisms of long covid remain unclear. The longer term consequences of infection with covid-19 on the brain, particularly in terms of neurodegeneration, will only become apparent with time and long term follow-up.

Mortality following mechanical thrombectomy for ischemic stroke in patients with COVID-19

OBJECTIVES

Multiple prior studies have shown a relationship between COVID-19 and strokes; further, COVID-19 has been shown to influence both time-to-thrombectomy and overall thrombectomy rates. Using large-scale, recently released national data, we assessed the association between COVID-19 diagnosis and patient outcomes following mechanical thrombectomy.

MATERIALS AND METHODS

Patients in this study were identified from the 2020 National Inpatient Sample. All patients with arterial strokes undergoing mechanical thrombectomy were identified using ICD-10 coding criteria. Patients were further stratified by COVID diagnosis (positive vs. negative). Other covariates, including patient/hospital demographics, disease severity, and comorbidities were collected. Multivariable analysis was used to determine the independent effect of COVID-19 on in-hospital mortality and unfavorable discharge.

RESULTS

5078 patients were identified in this study; 166 (3.3%) were COVID-19 positive. COVID-19 patients had a significantly higher mortality rate (30.1% vs. 12.4%, p < 0.001). When controlling for patient/hospital characteristics, APR-DRG disease severity, and Elixhauser Comorbidity Index, COVID-19 was an independent predictor of increased mortality (OR 1.13, p = 0.002). COVID-19 was not significantly related to discharge disposition (p = 0.480). Older age and increased APR-DRG disease severity were also correlated with increase morality.

CONCLUSIONS

Overall, this study indicates that COVID-19 is a predictor of mortality among mechanical thrombectomy. This finding is likely multifactorial but may be related to multisystem inflammation, hypercoagulability, and re-occlusion seen in COVID-19 patients. Further research would be needed to clarify these relationships.

COVID-19 and Cerebrovascular Disease

COVID-19 has been associated with numerous neurological complications, with acute cerebrovascular disease being one of the most devastating complications. Ischemic stroke is the most common cerebrovascular complication of COVID-19, affecting between 1 and 6% of all patients. Underlying mechanisms for COVID-related ischemic strokes are thought to be due to vasculopathy, endotheliopathy, direct invasion of the arterial wall, and platelet activation. Other COVID-19-associated cerebrovascular complications include hemorrhagic stroke, cerebral microbleeds, posterior reversible encephalopathy syndrome, reversible cerebral vasoconstriction syndrome, cerebral venous sinus thrombosis, and subarachnoid hemorrhage. This article discusses the incidence of these cerebrovascular complications, risk factors, management strategies, prognosis and future research directions, as well as considerations in pregnancy-related cerebrovascular events in the setting of COVID-19.

The impact of SARS-CoV-2 infection on the outcome of acute ischemic stroke-A retrospective cohort study

BACKGROUND

Acute ischemic stroke (AIS) is a common complication of severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2) infection (COVID-19), but the prognosis of these patients is poorly understood.

PURPOSE

To explore the impact of COVID-19 on neurological outcomes in AIS patients.

METHODS

A comparative retrospective cohort study was conducted in 32 consecutive AIS patients with and 51 without COVID-19 between the 1st of March 2020 and 1st of May 2021. The evaluation was based on a detailed chart review for demographic data, medical history, stroke severity, cranial and vessel imaging results, laboratory parameters, COVID-19 severity, hospitalization time, in-hospital mortality, and functional deficits at discharge (modified Rankin Scale, mRS).

RESULTS

COVID-19 AIS patients showed tendency to worse initial neurological deficit (NIHSS 9 (3-13) vs. 4 (2-10); p = 0.06), higher rate of large vessel occlusion (LVO; 13/32 vs. 14/51; p = 0.21), had prolonged hospitalization (19.4 ± 17.7 vs. 9.7 ± 7 days; p = 0.003), had lower chance of functional independence (mRS≤2) (12/32 vs. 32/51; p = 0.02) and showed higher in-hospital mortality (10/32 vs. 6/51; p = 0.02). In COVID-19 AIS patients, LVO was more common with COVID-19 pneumonia than without (55.6% vs. 23.1%; p = 0.139).

CONCLUSION

COVID-19-related AIS carries a worse prognosis. COVID-19 with pneumonia seems to be associated with a higher rate of LVO.

COVID-19 and Acute Ischemic Stroke Mortality and Clinical Outcomes among Hospitalized Patients in the United States: Insight from National Inpatient Sample

Coronavirus-19, primarily a respiratory virus, also affects the nervous system. Acute ischemic stroke (AIS) is a well-known complication among COVID-19 infections, but large-scale studies evaluating AIS outcomes related to COVID-19 infection remain limited. We used the National Inpatient Sample database to compare acute ischemic stroke patients with and without COVID-19. A total of 329,240 patients were included in the study: acute ischemic stroke with COVID-19 (n = 6665, 2.0%) and acute ischemic stroke without COVID-19 (n = 322,575, 98.0%). The primary outcome was in-hospital mortality. Secondary outcomes included mechanical ventilation, vasopressor use, mechanical thrombectomy, thrombolysis, seizure, acute venous thromboembolism, acute myocardial infarction, cardiac arrest, septic shock, acute kidney injury requiring hemodialysis, length of stay, mean total hospitalization charge, and disposition. Acute ischemic stroke patients who were COVID-19-positive had significantly increased in-hospital mortality compared to acute ischemic stroke patients without COVID-19 (16.9% vs. 4.1%, aOR: 2.5 [95% CI 1.7-3.6], p < 0.001). This cohort also had significantly increased mechanical ventilation use, acute venous thromboembolism, acute myocardial infarction, cardiac arrest, septic shock, acute kidney injury, length of stay, and mean total hospitalization charge. Further research regarding vaccination and therapies will be vital in reducing worse outcomes in patients with acute ischemic stroke and COVID-19.

Mechanical Thrombectomy in Acute Ischemic Stroke COVID-19 and Non-COVID-19 Patients: A Single Comprehensive Stroke Center Study

Coronavirus disease 2019 (COVID-19) increases the risk for thromboembolic events, such as acute ischemic stroke (AIS). Mechanical thrombectomy (MT) is a therapy of choice in early diagnosed AIS; however, its success and outcomes in COVID-19 patients are contradictory. This study presented our experience with MT performed in COVID-19 patients compared to a control group. The retrospective analysis included patients with AIS who underwent MT from April 2021 to April 2022 at our institution. There were 13 COVID-19-related patients (with active or past COVID-19 infection) and 55 non-COVID-19 patients (negative COVID-19 status). We analyzed patients' baseline clinical and laboratory data, modified Thrombolysis in Cerebral Infarction (mTICI) scale, used 24 h follow-up CT findings, and modified the Rankin scale. The COVID-19 group had higher values of leukocytes, neutrophils, neutrophil/leukocyte ratios, ASL, ALT, LDH and CRP, and lower values of lymphocytes compared to the control group. The AIS mostly occurred in posterior circulation in the COVID-19 group, while anterior circulation was more affected in the control group. Treatment approach and successful reperfusion did not differ between groups. In conclusion, although differences in some clinical and laboratory parameters between COVID-19 and non-COVID-19 groups were found, the outcomes of mechanical thrombectomy were equal.

Clinical features of thrombosis and bleeding in COVID-19

Infection with the SARS-CoV-2 virus, resulting in COVID-19 disease, has presented a unique scenario associated with high rates of thrombosis. The risk of venous thrombosis is some three- to sixfold higher than for patients admitted to a hospital for other indications, and for patients who have thrombosis, mortality appears to increase. Thrombosis may be a presenting feature of COVID-19. Pulmonary thrombi are the most frequent events, some related to deep vein thrombosis, but also to in situ microvascular and macrovascular thrombosis. Other venous thromboses include catheter- and circuit-associated in patients requiring hemofiltration and extracorporeal membrane oxygenation. Arterial thrombosis is less commonly documented, with 3% of patients in intensive care units having major arterial strokes and up to 9% having myocardial infarction, both of which are most likely multifactorial. Risk factors for thrombosis above those already documented in hospital settings include duration of COVID-19 symptoms before admission to the hospital. Laboratory parameters associated with higher risk of thrombosis include higher D-dimer, low fibrinogen, and low lymphocyte count, with higher factor VIII and von Willebrand factor levels indicative of more severe COVID-19 infection. All patients should receive thromboprophylaxis when admitted with COVID-19 infection, but the dose and length of treatment are still debated. Thrombosis continues to be treated according to standard VTE guidelines, but adjustments may be needed depending on other factors relevant to the patient's admission.