Recanalization, reperfusion, and recirculation in stroke

Recirculation, from arterial inflow routes through venous outflow pathways, was conceptualized in stroke research 50 years ago. As new technologies were developed, blocked arteries could be reopened, capillaries could be reperfused, and the use of recanalization and reperfusion grew to dominate therapeutic strategies. These approaches overwhelmingly focused on restoration of arterial and capillary inflow, but not on veins even though venous disorders may initiate or exacerbate brain injury. In this commentary, we advance the term "recirculation" after "recanalization" and "reperfusion" as a primary concept of stroke pathophysiology that targets the restoration of both the arterial and venous cerebral circulations.

Targeting Vascular Neural Network in Intracerebral Hemorrhage

BACKGROUND

Intracerebral hemorrhage (ICH) is a common type of stroke associated with high mortality and morbidity. Recent randomized controlled trials could not prove that the current strategies are effective at improving the final outcome of the ICH patients.

METHODS

Here we want to explore potential intervention targets for ICH based on the framework of the vascular neural network (VNN). In this review, a brief history of the evolution of stroke pathophysiology from humoral theory to VNN is discussed.

RESULTS

As current literature on pathophysiology of ICH is mainly focused on neuroprotection, here we want to evolve the central paradigm towards VNN. We stress mechanisms of vascular disruption and impaired blood flow harmony, which are clinically relevant but have received less attention in basic research.

CONCLUSION

We propose that VNN could be a robust and practical paradigm in both ICH basic research and clinical practice.

The Role of Arginine-Vasopressin in Stroke and the Potential Use of Arginine-Vasopressin Type 1 Receptor Antagonists in Stroke Therapy: A Narrative Review

Stroke is a life-threatening condition in which accurate diagnoses and timely treatment are critical for successful neurological recovery. The current acute treatment strategies, particularly non-invasive interventions, are limited, thus urging the need for novel therapeutical targets. Arginine vasopressin (AVP) receptor antagonists are emerging as potential targets to treat edema formation and subsequent elevation in intracranial pressure, both significant causes of mortality in acute stroke. Here, we summarize the current knowledge on the mechanisms leading to AVP hyperexcretion in acute stroke and the subsequent secondary neuropathological responses. Furthermore, we discuss the work supporting the predictive value of measuring copeptin, a surrogate marker of AVP in stroke patients, followed by a review of the experimental evidence suggesting AVP receptor antagonists in stroke therapy. As we highlight throughout the narrative, critical gaps in the literature exist and indicate the need for further research to understand better AVP mechanisms in stroke. Likewise, there are advantages and limitations in using copeptin as a prognostic tool, and the translation of findings from experimental animal models to clinical settings has its challenges. Still, monitoring AVP levels and using AVP receptor antagonists as an add-on therapeutic intervention are potential promises in clinical applications to alleviate stroke neurological consequences.

A severity comparison of leukoaraiosis in ischemic and hemorrhagic stroke: a retrospective study

Introduction

Leukoaraiosis (LA) is a common neuroradiological finding in patients suffering from stroke. Cerebral small-vessel disease (SVD) is one of the primary causes of both ischemic stroke and hemorrhagic stroke (intracerebral hemorrhage, ICH) and the development of LA. Significant evidence that LA predicts the risk of functional dependency and mortality exists. However, studies examining the difference in LA severity between ischemic stroke and hemorrhagic stroke are lacking. We therefore aimed to compare the severity and abundance of LA in the two stroke subgroups.

Methods

All patients admitted to the Department of Neurology, Haukeland University Hospital, with an ischemic stroke and intracerebral hemorrhagic (ICH) stroke diagnosed between 2006 and 2020 were included in the study. We collected patient data on risk factors and clinical and radiological findings and outcomes from our local stroke registry. The presence and severity of LA were assessed using the Fazekas score based on CT imaging. We evaluated the outcome using the modified Rankin Score (mRS) 7 days post-stroke.

Results

A total of 5,084 patients were included in our analyses: 4437 (87%) with ischemic stroke and 647 (13%) with ICH. LA was present in 2476 (45%) patients. In our ordinal logistic regression model, adjusting for age, sex, known hypertension, known diabetes mellitus, and smoking, LA was more severe and more abundant in ICH patients compared to ischemic stroke patients (Fazekas score: 1, OR: 1.54; Fazekas score: 2, OR: 1.88; and Fazekas score: 3, OR 2.13; p < 0.001). Increasing severity of LA was associated with worse functional outcomes in both groups (ischemic stroke, OR: 1.49; p < 0.001 and ICH, OR: 1.36; p < 0.025).

Conclusion

In this study, LA was more severe and abundant in patients with ICH.