Disappearance of the hyperdense MCA sign after stroke thrombolysis: implications for prognosis and early patient selection for clot retrieval

Prognostic capacity of hyperdense middle cerebral artery sign in anterior circulation acute ischaemic stroke patients receiving reperfusion therapy: a systematic review and meta-analysis

Pre-intervention CT imaging-based biomarkers, such as hyperdense middle cerebral artery sign (HMCAS) may have a role in acute ischaemic stroke prognostication. However, the clinical utility of HMCAS in settings of reperfusion therapy and the level of prognostic association is still unclear. This systematic review and meta-analysis investigated the association of HMCAS sign with clinical outcomes and its prognostic capacity in acute ischaemic stroke patients treated with reperfusion therapy. Prospective and retrospective studies from the following databases were retrieved from EMBASE, MEDLINE and Cochrane. Association of HMCAS with functional outcome, symptomatic intracerebral haemorrhage (sICH) and mortality were investigated. The random effect model was used to calculate the risk ratio (RR). Subgroup analyses were performed for subgroups of patients receiving thrombolysis (tPA), mechanical thrombectomy (EVT) and/or combined therapy (tPA + EVT). HMCAS significantly increased the rate of poor functional outcome by 1.43-fold in patients (RR 1.43; 95% CI 1.30-1.57; p < 0.0001) without any significant differences in sICH rates (RR 0.91; 95% CI 0.68-1.23; p = 0.546) and mortality (RR 1.34; 95% CI 0.72-2.51; p = 354) in patients with positive HMCAS as compared to negative HMCAS. In subgroup analyses, significant association between HMCAS and 90 days functional outcome was observed in patients receiving tPA (RR 1.53; 95% CI 1.40-1.67; p < 0.0001) or both therapies (RR 1.40; 95% CI 1.08-1.80; p = 0.010). This meta-analysis demonstrated that pre-treatment HMCAS increases risk of poor functional outcomes. However, its prognostic sensitivity and specificity in predicting long-term functional outcome, mortality and sICH after reperfusion therapy is poor.

Implications of the Presence of Hyperdense Middle Cerebral Artery Sign in Determining the Subtypes of Stroke Etiology

Background

Identifying stroke subtypes is crucial in choosing appropriate treatment, predicting outcomes, and managing recurrent stroke prevention.

Objectives

To study the association of hyperdense middle cerebral artery sign (HMCAS) on noncontrast computed tomography (NCCT) brain and subtypes of stroke etiology.

Methods

This is a retrospective hypothesis testing study. Patients aged 18 or over who had middle cerebral artery occlusion symptoms with HMCAS with verification on brain NCCT and received intravenous thrombolysis between January 2016 and June 2019 were enrolled. The demographic data, clinical outcomes, stroke subtypes, and characteristics of HMCAS were collected from medical records.

Results

Ninety-nine out of 299 enrolled patients presented with HMCAS. The most common stroke subtype was cardioembolism (59%). Of the baseline characteristics, hypertension was more common in cases of large-artery atherosclerosis (LAA) (86.4%), and atrial fibrillation (AF) was the highest in cardioembolism (44.8%). HMCAS disappearance in cardioembolism was lowest compared to LAA and others (63% vs. 91% vs. 94.7%, respectively). The univariable analysis found that HMCAS disappearance is significantly associated with all stroke subtypes (Odds ratio, 95% confidence interval 10.58, 1.31-85.43; P = 0.027 for other and 5.88, 1.24-27.85; P = 0.026 for LAA). Multinomial logistic regression found that body weight and hypertension were associated with the LAA subtype. AF and intracranial hemorrhage (ICH) were associated with cardioembolism.

Conclusion

The most likely diagnosis from the presence of HMCAS is cardioembolism, but the definite stroke etiologic subtype can not be identified. Combining the patient risk factors, including body weight, hypertension, and AF, with HMCAS and its characteristics will predict stroke subtypes more accurately.

Examining Outcomes following Thrombolysis in An Increasingly Older and Dependent Stroke Population

Background

Thrombolysis for acute ischaemic stroke (AIS) patients aged ≥80 years is evidence based, although its use in previously dependent patients is controversial.

Methods

Data from 831 thrombolysed AIS patients in our centre from 2009–2017 were used to compare demographic trends and outcomes (haemorrhage, mortality, three-month independence) in patients aged <80 and ≥80 years and with prior dependency. Comparison with UK and world registry data regarding age and pre-stroke dependency was made.

Results

The percentage of treated patients aged ≥80 years increased year-on-year, doubling from 25% to 50% (p<0.01), with increasing average age and pre-stroke dependency in world centres. Patients ≥80 years had higher (p<0.001) stroke severity, symptomatic intracerebral haemorrhage (5% vs. 1.5%), mortality (35% vs. 13%) and lower three month independent survival (24% vs. 60%). Patients with pre-stroke dependency had especially higher three month mortality (57–71%, OR 3.75 [95% CI 1.97–7.15]) in both age groups.

Conclusion

Patients aged ≥80 years and with dependency increasingly receive thrombolysis. Given poorer outcomes thrombolysis trials are needed in pre-stroke dependent patients.

Revolution in acute ischaemic stroke care: a practical guide to mechanical thrombectomy

Rapid, safe and effective arterial recanalisation to restore blood flow and improve functional outcome remains the primary goal of hyperacute ischaemic stroke management. The benefit of intravenous thrombolysis with recombinant tissue-type plasminogen activator for patients with severe stroke due to large artery occlusion is limited; early recanalisation is generally less than 30% for carotid, proximal middle cerebral artery or basilar artery occlusion. Since November 2014, nine positive randomised controlled trials of mechanical thrombectomy for large vessel occlusion in the anterior circulation have led to a revolution in the care of patients with acute ischaemic stroke. Its efficacy is unmatched by any previous therapy in stroke medicine, with a number needed to treat of less than 3 for improved functional outcome. With effectiveness shown beyond any reasonable doubt, the key challenge now is how to implement accessible, safe and effective mechanical thrombectomy services. This review aims to provide neurologists and other stroke physicians with a summary of the evidence base, a discussion of practical aspects of delivering the treatment and future challenges. We aim to give guidance on some of the areas not clearly described in the clinical trials (based on evidence where available, but if not, on our own experience and practice) and highlight areas of uncertainty requiring further research.