Stroke Prevention in Cervical Artery Dissection.

PURPOSE OF REVIEW: Cervical artery dissection (CAD) is rare, yet it is a common cause of stroke in young and middle-aged adults. Historically, some senior clinicians favored anticoagulation in the prevention of stroke due to CAD. Choosing the optimal antithrombotic treatment with either antiplatelet (AP) or anticoagulant (AC) medications remains a challenge. This paper will review the clinical features and imaging of CAD, and the acute treatment and prevention of stroke due to CAD. RECENT FINDINGS: Until 2015, there were no prospective randomized trials in the optimal antithrombotic management of CAD. The Cervical Artery Dissection in Stroke Study (CADISS) trial found that treatment with AC did not lower the risk of subsequent stroke or death at 3 months when compared to AP agents. This led to a paradigm shift in national guidelines. In 2021, The Biomarkers and Antithrombotic Treatment in of Cervical Artery Dissection (TREAT-CAD) trial however did not confirm the non-inferiority of AP therapy in stroke prevention due to CAD. The optimal antithrombotic management for stroke prevention in CAD remains uncertain, while the superiority of anticoagulation has not been established, nor has the non-inferiority of AP agents. The future direction of research should consider early preventative treatment, dual treatment with AP agents, direct oral AC medications, and aggregation of data from existing randomized trials.

Machine learning models improve prediction of large vessel occlusion and mechanical thrombectomy candidacy in acute ischemic stroke.

BACKGROUND AND PURPOSE: Early identification of large vessel occlusions (LVO) and timely recanalization are paramount to improved clinical outcomes in acute ischemic stroke. A stroke assessment that maximizes sensitivity and specificity for LVOs is needed to identify these cases and not overburden the health system with unnecessary transfers. Machine learning techniques are being used for predictive modeling in many aspects of stroke care and may have potential in predicting LVO presence and mechanical thrombectomy (MT) candidacy. METHODS: Ischemic stroke patients treated at Loyola University Medical Center from July 2018 to June 2019 (N = 286) were included. Thirty-five clinical and demographic variables were analyzed using machine learning algorithms, including logistic regression, extreme gradient boosting, random forest (RF), and decision trees to build models predictive of LVO presence and MT candidacy by area of the curve (AUC) analysis. The best performing model was compared with prior stroke scales. RESULTS: When using all 35 variables, RF best predicted LVO presence (AUC = 0.907 ± 0.856-0.957) while logistic regression best predicted MT candidacy (AUC = 0.930 ± 0.886-0.974). When compact models were evaluated, a 10-feature RF model best predicted LVO (AUC = 0.841 ± 0.778-0.904) and an 8-feature RF model best predicted MT candidacy (AUC = 0.862 ± 0.782-0.942). The compact RF models had sensitivity, specificity, negative predictive value and positive predictive value of 0.81, 0.87, 0.92, 0.72 for LVO and 0.87, 0.97, 0.97, 0.86 for MT, respectively. The 10-feature RF model was superior at predicting LVO to all previous stroke scales (AUC 0.944 vs 0.759-0.878) and the 8-feature RF model was superior at predicting MT (AUC 0.970 vs 0.746-0.834). CONCLUSION: Random forest machine learning models utilizing clinical and demographic variables predicts LVO presence and MT candidacy with a high degree of accuracy in an ischemic stroke cohort. Further validation of this strategy for triage of stroke patients requires prospective and external validation.

Neurologic complications of cardiac arrest.

Cardiac arrest is a catastrophic event with high morbidity and mortality. Despite advances over time in cardiac arrest management and postresuscitation care, the neurologic consequences of cardiac arrest are frequently devastating to patients and their families. Targeted temperature management is an intervention aimed at limiting postanoxic injury and improving neurologic outcomes following cardiac arrest. Recovery of neurologic function governs long-term outcome after cardiac arrest and prognosticating on the potential for recovery is a heavy burden for physicians. An early and accurate estimate of the potential for recovery can establish realistic expectations and avoid futile care in those destined for a poor outcome. This chapter reviews the epidemiology, pathophysiology, therapeutic interventions, prognostication, and neurologic sequelae of cardiac arrest.

The use of stent retrievers in acute ischemic stroke.

INTRODUCTION: Acute ischemic stroke (AIS) is one of the leading causes of mortality and adult disability worldwide. For two decades, the preferred approach for AIS was intravenous recombinant tissue plasminogen activator (IV tPA). However, IV tPA cannot be given to many AIS patients who do not meet strict criteria for its use. IV tPA has also had lesser benefit in patients with large clot burden in the context of large vessel occlusion (LVO). AREAS COVERED: Endovascular stroke therapy had been an 'unproven' therapy despite numerous trials of intra-arterial pharmacologic thrombolysis and mechanical thrombectomy. With the advent of stent-retriever devices, there has been a paradigm shift in the utilization of endovascular therapies for AIS. Our review discusses cerebrovascular hemodynamics, the basis of the recanalization models in AIS, aspects of intravenous thrombolysis, prior generations of endovascular therapy, and the recent successful AIS stent retriever trials. Expert commentary: Recently 'stent-retrievers', a new generation of mechanical thrombectomy devices, were shown to be associated with improved functional outcomes in AIS secondary to proximal intracranial anterior circulation LVO. Stent retrievers are a major advance in AIS care and will have significant impact on the evolution of stroke systems of care.

Early administration of therapeutic anticoagulation following intravenous thrombolysis for acute cardiogenic embolic stroke caused by left ventricular thrombus: case report and topic review.

Cardiogenic cerebral embolism represents 20% of all acute ischemic strokes (AISs) with one-third of these being caused by left ventricular thrombus (LVT). LVT is not a contraindication for treatment with intravenous recombinant tissue plasminogen activator (IV rtPA) for AIS. However, the subsequent treatment of a potentially unstable LVT is contraindicated for 24 h following the use of IV rtPA according to current guidelines. We present a 66-year-old man with AIS treated with IV rtPA. Echocardiogram shortly after treatment demonstrated both a large apical and septal thrombus in the left ventricle and at 12 h post IV rtPA infusion, therapeutic anticoagulation with heparin was started without complication. In practice, the action of IV rtPA outlasts its apparent half-life because of thrombin-binding and the prolonged effects and longer half-life of its product, plasmin; however, the pharmacokinetics do not warrant prolonged avoidance of therapeutic anticoagulation when clinically indicated. Our case demonstrates that anticoagulation for potentially unstable LVT can be safely initiated at 12 h following IV rtPA treatment for AIS.

Do not forget Susac syndrome in patients with unexplained acute confusion.

BACKGROUND: To report 2 patients with Susac syndrome presenting with acute confusion and abnormal neuroimaging and cerebrospinal fluid (CSF) findings, both of whom were initially misdiagnosed. Susac syndrome is a rare, though likely underdiagnosed, endotheliopathy defined clinically by the triad of encephalopathy, branch retinal artery occlusions (BRAOs), and sensorineural hearing loss (SNHL). Its pathogenesis remains poorly understood. The classic clinical triad may not be fully developed at initial presentation, even at the time magnetic resonance imaging (MRI) demonstrates characteristic central corpus callosum lesions. METHODS: We describe the patient's clinical course, investigations, management, and follow-up. RESULTS: A 57-year-old woman had acute onset of confusion and was initially thought to have multiple strokes. MRI demonstrated restricted diffusion involving the splenium of the corpus callosum and CSF showed elevated protein levels. Audiometry showed asymmetric bilateral SNHL. Fluorescein angiography showed multiple bilateral BRAOs. Patient received corticosteroids and intravenous immunoglobulin (IVIG). At 1-month follow-up, patient's confusion had resolved. The second patient was a 32-year-old man who had acute onset of confusion. CSF demonstrated pleocytosis and elevated protein. MRI demonstrated restricted diffusion involving the corpus callosum. Patient was discharged and rehospitalized 20 days later where he was diagnosed with acute disseminated encephalomyelitis. Patient presented a third time with vision loss. Fluorescein angiography demonstrated bilateral BRAOs. Audiometry noted bilateral SNHL. He received IVIG and discharged on a prednisone taper and mycophenolate mofetil. At 1-month follow-up, patient's confusion had resolved. CONCLUSIONS: We report 2 patients evaluated within 1 month of each other who presented with acute confusion and were eventually diagnosed with Susac syndrome. Susac syndrome should be considered in young patients with otherwise unexplained acute onset of confusion with MRI and CSF changes as described previously.