The prognostic factors that influence long-term survival in acute large cerebral infarction

A new machine learning model to predict the prognosis of cardiogenic brain infarction

Cardiogenic cerebral infarction (CCI) is a disease in which the blood supply to the blood vessels in the brain is insufficient due to atherosclerosis or stenosis of the coronary arteries in the patient's heart, which leads to neurological deficits. To predict the pathogenic factors of cardiogenic cerebral infarction, this paper proposes a machine learning based analytical prediction model. 494 patients with CCI who were hospitalized for the first time were consecutively included in the study between January 2017 and December 2021, and followed up every three months for one year after hospital discharge. Clinical, laboratory and imaging data were collected, and predictors associated with relapse and death in CCI patients at six months and one year after discharge were analyzed using univariate and multivariate logistic regression methods, meanwhile established a new machine learning model based on the enhanced moth-flame optimization (FTSAMFO) and the fuzzy K-nearest neighbor (FKNN), called BITSAMFO-FKNN, which is practiced on the dataset related to patients with CCI. Specifically, this paper proposes the spatial transformation strategy to increase the exploitation capability of moth-flame optimization (MFO) and combines it with the tree seed algorithm (TSA) to increase the search capability of MFO. In the benchmark function experiments FTSAMFO beat 5 classical algorithms and 5 recent variants. In the feature selection experiment, ten times ten-fold cross-validation trials showed that the BITSAMFO-FKNN model proved actual medical importance and efficacy, with an accuracy value of 96.61%, sensitivity value of 0.8947, MCC value of 0.9231, and F-Measure of 0.9444. The results of the trial showed that hemorrhagic conversion and lower LVDD/LVSD were independent risk factors for recurrence and death in patients with CCI. The established BITSAMFO-FKNN method is helpful for CCI prognosis and deserves further clinical validation.

Mechanical Thrombectomy with Intravenous Thrombolysis versus Thrombolysis Alone for the Treatment of Stroke: A Systematic Review of Economic Evaluations

Mechanical thrombectomy has revolutionized the management of stroke by improving the recanalization rates and reducing deleterious consequences. It is now the standard of care despite the high financial cost. A considerable number of studies have evaluated its cost effectiveness. Therefore, this study aimed to identify economic evaluations of mechanical thrombectomy with thrombolysis compared with thrombolysis alone to provide an update of existing evidence, focusing on the period after proof of effectiveness of mechanical thrombectomy. Twenty-one studies were included in the review: 18 were model-based economic evaluations to simulate long-term outcomes and costs, and 19 were conducted in high-income countries. Incremental cost-effectiveness ratios ranged from -$5,670 to $74,216 per quality-adjusted life year. Mechanical thrombectomy is cost-effective in high-income countries and in the populations selected for clinical trials. However, most of the studies used the same data. There is a lack of real-world and long-term data to analyze the cost effectiveness of mechanical thrombectomy in treating the global burden of stroke.

MRI Radiomics and Predictive Models in Assessing Ischemic Stroke Outcome-A Systematic Review

Stroke is a leading cause of disability and mortality, resulting in substantial socio-economic burden for healthcare systems. With advances in artificial intelligence, visual image information can be processed into numerous quantitative features in an objective, repeatable and high-throughput fashion, in a process known as radiomics analysis (RA). Recently, investigators have attempted to apply RA to stroke neuroimaging in the hope of promoting personalized precision medicine. This review aimed to evaluate the role of RA as an adjuvant tool in the prognosis of disability after stroke. We conducted a systematic review following the PRISMA guidelines, searching PubMed and Embase using the keywords: 'magnetic resonance imaging (MRI)', 'radiomics', and 'stroke'. The PROBAST tool was used to assess the risk of bias. Radiomics quality score (RQS) was also applied to evaluate the methodological quality of radiomics studies. Of the 150 abstracts returned by electronic literature research, 6 studies fulfilled the inclusion criteria. Five studies evaluated predictive value for different predictive models (PMs). In all studies, the combined PMs consisting of clinical and radiomics features have achieved the best predictive performance compared to PMs based only on clinical or radiomics features, the results varying from an area under the ROC curve (AUC) of 0.80 (95% CI, 0.75-0.86) to an AUC of 0.92 (95% CI, 0.87-0.97). The median RQS of the included studies was 15, reflecting a moderate methodological quality. Assessing the risk of bias using PROBAST, potential high risk of bias in participants selection was identified. Our findings suggest that combined models integrating both clinical and advanced imaging variables seem to better predict the patients' disability outcome group (favorable outcome: modified Rankin scale (mRS) ≤ 2 and unfavorable outcome: mRS > 2) at three and six months after stroke. Although radiomics studies' findings are significant in research field, these results should be validated in multiple clinical settings in order to help clinicians to provide individual patients with optimal tailor-made treatment.

Cost-effective analysis of mechanical thrombectomy (MT) in patients with poor baseline modified Rankin Score (mRS)

Mechanical thrombectomy (MT) has been established as a standard of care for patients with acute ischemic stroke for the past five years. However, the direct benefits of this treatment in patients with baseline disability remains unclear. This study aims to elucidate the cost impact of performing MT on patients with moderate-to-severe baseline disability to work towards an optimized system of care for acute ischemic stroke. We developed a Markov economic model with a life-time horizon analysis of costs associated with mechanical thrombectomy in patients grouped on baseline disability as defined by modified Rankin Score. Our clinical and economic data is based on an American payer perspective. Our results identified a marginal cost-effective ratio (mCER) of $18,835.00 per quality-adjusted life year (QALY) when mechanical thrombectomy is reserved as a treatment only for patients with no-to-minimal baseline disability as compared to those with any level of baseline disability. Our results provide a framework for these future studies and highlight key sectors that drive cost in the surgical treatment and life-long care of patients with acute ischemic stroke.

Determining cut-off points in functional assessment scales in stroke

BACKGROUND

A wide variety of well-validated assessment scales of functioning and disability have been developed for stroke population. However, these instruments have limitations in their interpretation. Therefore, determining cut-off points for their categorization becomes necessary.

OBJECTIVES

To determine cut-off points for the BI, FIM and FAM scales to differentiate clinical disability categories and to establish the relationship between mRS and DOS scales.

METHODS

One hundred and six adults with ischemic or haemorrhagic stroke were mainly recruited from a rehabilitation facility (Hospitales Nisa, Valencia, Spain).

RESULTS

A high correlation was observed between the DOS and mRS scales (Kendall's tau-b = 0.475; p = 0.000) although a certain amount of disagreement between the two scales was detected. The cut-off points were 62.90 (95% CI, 57.26-69.29) and 21.30 (95% CI, 16.34-26.03) for the BI; 70.62 (95% CI, 66.65-75.22) and 38.29 (95% CI, 34.07-42.25) for the FIM; and 116.07 (95% CI, 110.30-122.68) and 66.02 (95% CI, 59.20-72.35) for the FAM.

CONCLUSION(S)

DOS was observed to be more demanding than the mRS, in terms of patient independence. Additionally, the lower cut-off points separating the levels of severe and moderate disability in the BI, FIM and FAM were determined. These findings would facilitate practitioners clinical interpretation of disability levels in post-stroke patients.

Novel model of direct and indirect cost-benefit analysis of mechanical embolectomy over IV tPA for large vessel occlusions: a real-world dollar analysis based on improvements in mRS

BACKGROUND

Ischemic strokes result in significant healthcare expenditures (direct costs) and loss of quality-adjusted life years (QALYs) (indirect costs). Interventional therapy has demonstrated improved functional outcomes in patients with large vessel occlusions (LVOs), which are likely to reduce the economic burden of strokes.

OBJECTIVE

To develop a novel real-world dollar model to assess the direct and indirect cost-benefit of mechanical embolectomy compared with medical treatment with intravenous tissue plasminogen activator (IV tPA) based on shifts in modified Rankin scores (mRS).

METHOD

A cost model was developed including multiple parameters to account for both direct and indirect stroke costs. These were adjusted based upon functional outcome (mRS). The model compared IV tPA with mechanical embolectomy to assess the costs and benefits of both therapies. Direct stroke-related costs included hospitalization, inpatient and outpatient rehabilitation, home care, skilled nursing facilities, and long-term care facility costs. Indirect costs included years of life expectancy lost and lost QALYs. Values for the model cost parameters were derived from numerous resources and functional outcomes were derived from the MR CLEAN study as a reflective sample of LVOs. Direct and indirect costs and benefits for the two treatments were assessed using Microsoft Excel 2013.

RESULTS

This cost-benefit model found a cost-benefit of mechanical embolectomy over IV tPA of $163 624.27 per patient and the cost benefit for 50 000 patients on an annual basis is $8 181 213 653.77.

CONCLUSIONS

If applied widely within the USA, mechanical embolectomy will significantly reduce the direct and indirect financial burden of stroke ($8 billion/50 000 patients).

Outcome following decompressive craniectomy for malignant middle cerebral artery infarction in patients older than 70 years old

Objective

Malignant middle cerebral artery (MCA) infarction occurs in 10% of all ischemic strokes and these severe strokes are associated with high mortality rates. Recent clinical trials demonstrated that early decompressive craniectomy reduce mortality rates and improves functional outcomes in healthy young patients (less than 61 years of age) with a malignant infarction. The purpose of this study was to assess the efficacy of decompressive craniectomy in elderly patients (older than 70 years of age) with a malignant MCA infarction.

Methods

Between February 2008 and October 2011, 131 patients were diagnosed with malignant MCA infarctions. We divided these patients into two groups: patients who underwent decompressive craniectomy (n = 58) and those who underwent conservative care (n = 73). A cut-off point of 70 years of age was set, and the study population was segregated into those who fell above or below this point. Mortality rates and functional outcome scores were assessed, and a modified Rankin Scale (mRS) score of > 3 was considered to represent a poor outcome.

Results

Mortality rates were significantly lower at 29.3% (one-month mortality rate) and 48.3% (six-month mortality rate) in the craniectomy group as compared to 58.9% and 71.2%, respectively, in the conservative care group (p < 0.001, p = 0.007). Age (≥70 years vs. < 70 years) did not statistically differ between groups for the six-month mortality rate (p = 0.137). However, the pre-operative National Institutes of Health Stroke Scale (NIHSS) score did contribute to the six-month mortality rate (p = 0.047).

Conclusion

Decompressive craniectomy is effective for patients with a malignant MCA infarction regardless of their age. Therefore, factors other than age should be considered and the treatment should be individualized in elderly patients with malignant infarctions.

[Thalamic Stroke and Associated Behavior Disorders. Possibilities for Integral Management: Case Report]

INTRODUCTION

Since ancient Greece, cerebrovascular accidents have been described with no variation. Even today, they are still a catastrophic event in the lives of patients with a high risk of disabling sequelae.

METHODOLOGY

Case report of a 56-year male patient with thalamic ischemia.

RESULTS

The intervention with integral strategies involving pharmacological management and cognitive interventions was decisive for the satisfactory evolution of the patient.

CONCLUSIONS

The management of patients with cerebrovascular accidents cannot be limited to the emergency room. Pharmacological advances in programs and cognitive intervention methods provide intervention tools from the very beginning of the stroke thus reducing the impact of long-term sequelae, and consequently enabling a better reintegration of the patient to his family.

[Advances in the pathophysiology and management of infections in the acute phase of stroke]

Infection in the acute phase of stroke has been identified as an independent predictor of poor outcome, both in the short and intermediate term. Various factors raising the risk of developing an infection (exposure to multiple pathogens, disruption of the protective function of the mucous membranes and a state of relative immunosuppression) coexist during the acute phase of stroke. Several risk factors have been identified for their development (especially increasing age and stroke severity). It has been proposed that infection contributes to a worse prognosis through different mechanisms, notably the development of an inflammatory response to brain tissue (with a potential to add secondary damage to that caused by the ischemic insult). Clinical trials evaluating the prophylactic and early administration of antibiotics to reduce the incidence of infection in the acute phase of stroke have yielded inconsistent results. Immunomodulating strategies, which may provide therapeutic alternatives in the future, are currently being evaluated.