Higher early recurrence risk and potential benefit of dual antiplatelet therapy for minor stroke with watershed infarction: subgroup analysis of CHANCE

Imaging Assessments and Clinical Significance of Brain Frailty in Moyamoya Disease

BACKGROUND AND PURPOSE

Imaging assessment of brain frailty in ischemic stroke has been extensively studied, while the correlation between brain frailty and Moyamoya disease remains obscure. This study aimed to investigate the imaging characteristics of brain frailty and its clinical applications in Moyamoya disease.

MATERIALS AND METHODS

This study included 60 patients with Moyamoya disease (107 hemispheres). All patients were divided into stroke and nonstroke groups based on clinical symptoms and imaging findings. The modified brain frailty score was adapted to consider 4 imaging signs: white matter hyperintensity, enlargement of perivascular space, old vascular lesions, and cerebral microbleed. The relative CBF of the MCA territory was quantified using pseudocontinuous arterial-spin labeling. Surgical outcome after revascularization surgery was defined by the Matsushima grade.

RESULTS

The relative CBF of the MCA territory decreased as the modified brain frailty score and periventricular white matter hyperintensity grades increased (ρ = -0.22, P = .02; ρ = -0.27, P = .005). Clinically, the modified brain frailty score could identify patients with Moyamoya disease with stroke (OR = 2.00, P = .02). Although the modified brain frailty score showed no predictive value for surgical outcome, basal ganglia enlargement of the perivascular space had a significant correlation with the postoperative Matsushima grade (OR = 1.29, P = .03).

CONCLUSIONS

The modified brain frailty score could reflect a cerebral perfusion deficit and clinical symptoms of Moyamoya disease, and its component basal ganglia enlargement of perivascular space may be a promising marker to predict surgical outcome and thus aid future clinical decision-making.

Diagnosis and treatment of Watershed strokes: a narrative review

Watershed strokes have been described previously as ischemic strokes located in vulnerable border zones between brain tissue supplied by the anterior, posterior, and middle cerebral arteries in the distal junction between two non-anastomotic arterial territories. Ischemic strokes in border zones are well-recognized entities and well-described in terms of imaging features, but the pathophysiological mechanism of brain injury production is not fully defined. Border zone ischemia is caused by cerebral hypoperfusion through decreased cerebral blood flow and arterial embolism in unstable atheroma plaque. It is often difficult to say which mechanisms are fully responsible for producing cerebral ischemic lesions. This review aimed to highlight the imaging aspect of watershed strokes and to correlate the clinical characteristics of this type of stroke with the diagnostic algorithm for optimal therapeutic management. Neurologists should promptly recognize this type of stroke and investigate its etiology in the shortest possible time.

Predictive factors for clinical outcomes in Filipino patients with watershed infarction: A single center study

Background and purpose

Watershed infarcts denote ischemic lesions involving the distal territories of two major arteries. For years, hypotheses on its pathophysiological mechanisms have been proposed. Yet, the cause is still widely debated. This study aimed to determine the mechanism of watershed strokes and compare their clinical outcomes to acute ischemic stroke from other causes and predict the factors affecting clinical outcomes in patients with watershed infarcts.

Methods

This single-center, comparative, six-years retrospective cohort study included patients with a diagnosis of Acute Ischemic Stroke. Patients were classified under watershed group or acute ischemic stroke based on their neuroimaging findings. Stroke mechanisms were determined between groups as well as the factors associated with clinical outcomes in watershed strokes.

Results

Among the 424 patients included in the study, large artery atherosclerosis was seen in greater frequency in patients with watershed infarcts regardless of the type (EWIs: n = 68, 73% vs IWIs: n = 89, 75%). No differences observed in the clinical outcomes between groups. Multiple variable analysis showed that age, female sex, high NIHSS score and presence of underlying malignancy were associated with clinical outcomes.

Conclusion

Clinical outcomes between watershed infarcts and acute ischemic strokes were similar. Hemodynamic compromise in the setting of severe stenosis is the underlying mechanism for both types of watershed strokes thus, the goal of treatment is to maintain adequate perfusion. High baseline NIHSS score, increased age, female gender and underlying malignancy were all poor predictors of clinical outcomes in patients with watershed strokes.

P2Y12 inhibitors plus aspirin for acute treatment and secondary prevention in minor stroke and high-risk transient ischemic attack: A systematic review and meta-analysis

BACKGROUND

Aspirin is a cornerstone of preventive treatment for stroke recurrence, but during the last few years the role of dual antiplatelet therapy (DAPT) is much more emerging.

OBJECTIVE

This systematic review aimed to compare early use of P2Y12 inhibitors (clopidogrel/ticagrelor) plus aspirin to aspirin alone for acute treatment and secondary prevention in acute non-cardioembolic minor ischemic stroke or TIA.

METHODS

A systematic search on MEDLINE and EMBASE was performed. Treatment effects were estimated with RRs and 95% CI. We used RevMan 5.4 for data analyses. We assessed methodological quality of selected studies according to Rob2 tools and quality of evidence with GRADE approach.

RESULTS

Four RCTs were included, enrolling 21,459 patients. Compared to aspirin alone, DAPT was superior in reducing stroke recurrence (RR 0.74, 95% CI 0.67-0.82, P <0.00001, absolute risk difference by 2%, NNT 50) and disabling stroke defined as mRS>2 (RR 0.84, 95% CI 0.75-0.95, P = 0.004), with no impact on all causes of mortality (RR 1.30, 95% CI 0.90-1.89, P = 0.16). An increased risk of major bleeding was emerged (RR 2.54, 95% CI 1.65-3.92, P <0.0001, absolute risk difference by 0,4%, NNH 250), in particular with ticagrelor, but there was no correlation between therapy duration and bleeding risk, as appeared from one-month (RR 3.06, 95% CI 1.64 to 5.69) and three-month (RR 2.09, 95% CI 1.18 to 3.69) follow-up analysis.

CONCLUSIONS

Early administration of P2Y12 inhibitors plus aspirin in patients with acute non-cardioembolic minor ischemic stroke or TIA reduced the incidence of ischemic stroke recurrence, impacting more significantly than the increased bleeding risk and influencing patients' quality of life by reducing disabling stroke.

The 2020 breakthroughs in early secondary prevention: dual antiplatelet therapy versus single antiplatelet therapy

PURPOSE OF REVIEW

Single antiplatelet therapy represents an established treatment in secondary prevention of ischemic strokes and transient ischemic attacks (TIAs). In contrast with coronary artery disease, the use of dual antiplatelet therapy (DAPT) for secondary prevention in patients with acute cerebral ischemia (ACI) remains under debate. In this narrative review, we present and analyse the most recent findings concerning the potential efficacy and safety of DAPT therapy after ischemic strokes or TIA.

RECENT FINDINGS

Following the publication of the three (CHANCE, POINT and THALES) large, randomized-controlled, clinical trials (RCTs) that showed efficacy of early DAPT for the secondary prevention after minor AIS or TIA, short-term DAPT use is becoming the most prevalent choice of treatment. Notably, DAPT is even more popular after AIS attributed to large artery atherosclerosis given randomized data from small RCTs supporting the use of DAPT in patients with extracranial or intracranial atherosclerosis and microembolization detected by transcranial Doppler. Recent subanalysis of data from the randomized trials aim to identify specific patient subgroups, which are determined by genetic, imaging or clinical characteristics, and for whom DAPT appears to be more beneficial. The potential role of different antiplatelet agents (aspirin, clopidogrel, ticagrelor) is also discussed.

SUMMARY

DAPT has recently proven its efficacy for the early secondary prevention of AIS patients with minor stroke severity and high-risk TIA patients. However, the length of DAPT is still controversial, as well as the individualized selection of AIS or TIA patients with the lower risk of bleeding and with the greater benefit in prevention of ischemic cerebrovascular and cardiovascular events.