Stroke-induced damage on the blood-brain barrier

The Hidden Heart: Exploring Cardiac Damage Post-Stroke: A Narrative Review

Stroke-heart syndrome (SHS), a critical yet underrecognized condition, encompasses a range of cardiac complications that arise following an ischemic stroke. This narrative review explores the pathophysiology, clinical manifestations, and implications of SHS, focusing on the complex interplay between the brain and the heart. Acute ischemic stroke (AIS) triggers autonomic dysfunction, leading to a surge in catecholamines and subsequent myocardial injury. Our review highlights the five cardinal manifestations of SHS: elevated cardiac troponin (cTn) levels, acute myocardial infarction, left ventricular dysfunction, arrhythmias, and sudden cardiac death. Despite the significant impact of these complications on patient outcomes, there is a notable absence of specific guidelines for their management. Through a comprehensive literature search, we synthesized findings from recent studies to elucidate the mechanisms underlying SHS and identified gaps in the current understanding. Our findings underscore the importance of early detection and multidisciplinary management of cardiac complications post-stroke. Future research should focus on establishing evidence-based protocols to improve clinical outcomes for stroke patients with SHS. Addressing this unmet need will enhance the care of stroke survivors and reduce mortality rates associated with cardiac complications.

Research progress in brain-targeted nasal drug delivery

The unique anatomical and physiological connections between the nasal cavity and brain provide a pathway for bypassing the blood-brain barrier to allow for direct brain-targeted drug delivery through nasal administration. There are several advantages of nasal administration compared with other routes; for example, the first-pass effect that leads to the metabolism of orally administered drugs can be bypassed, and the poor compliance associated with injections can be minimized. Nasal administration can also help maximize brain-targeted drug delivery, allowing for high pharmacological activity at lower drug dosages, thereby minimizing the likelihood of adverse effects and providing a highly promising drug delivery pathway for the treatment of central nervous system diseases. The aim of this review article was to briefly describe the physiological structures of the nasal cavity and brain, the pathways through which drugs can enter the brain through the nose, the factors affecting brain-targeted nasal drug delivery, methods to improve brain-targeted nasal drug delivery systems through the application of related biomaterials, common experimental methods used in intranasal drug delivery research, and the current limitations of such approaches, providing a solid foundation for further in-depth research on intranasal brain-targeted drug delivery systems (see Graphical Abstract).

Utilization of Mirror Visual Feedback for Upper Limb Function in Poststroke Patients: A Systematic Review and Meta-Analysis

Mirror visual feedback (MVF), a noninvasive treatment method, is attracting attention as a possibility to promote the recovery of upper limb function in stroke patients. However, the cognitive effects of this therapy have received limited attention in the existing literature. To address this gap, we conducted a systematic review and meta-analysis to investigate the relationship between upper limb function and cognition in stroke patients and to evaluate the effect of MVF on improving upper limb function. A comprehensive search was performed on the Embase, MEDLINE, and PubMed databases to identify original articles and clinical studies published between 2013 and 2022. Qualitative analysis was performed using the Cochrane Risk of Bias tool, and in the quantitative analysis, a random-effects model was used as the effect model, and standard mean difference (SMD) was used as the effect measure. Eight studies that met the inclusion criteria were entered in the analysis. Data extraction included an assessment tool for upper extremity function. Results of the quantitative analysis demonstrate that MVF was effective in improving upper extremity function in stroke patients (SMD = 0.94, 95% CI 0.69 to 1.20). In conclusion, this systematic review and meta-analysis provides evidence supporting the effectiveness of MVF in improving upper limb function in stroke patients. However, further studies are needed to investigate the cognitive effects of MVF and elucidate the underlying mechanisms.