Neuroimaging Prediction of Hemorrhagic Transformation for Acute Ischemic Stroke

<b><i>Background:</i></b> Hemorrhagic transformation (HT) is a common complication of acute ischemic stroke, often resulting from reperfusion therapy. Early prediction of HT can enable stroke neurologists to undertake measures to avoid clinical deterioration and make optimal treatment strategies. Moreover, the trend of extending the time window for reperfusion therapy (both for intravenous thrombolysis and endovascular treatment) further requires more precise detection of HT tendency. <b><i>Summary:</i></b> In this review, we summarized and discussed the neuroimaging markers of HT prediction of acute ischemic stroke patients, mainly focusing on neuroimaging markers of ischemic degree and neuroimaging markers of blood-brain barrier permeability. This review is aimed to provide a concise introduction of HT prediction and to elicit possibilities of future research combining advanced technology to improve the accessibility and accuracy of HT prediction under emergent clinical settings. <b><i>Key Messages:</i></b> Substantial studies have utilized neuroimaging, blood biomarkers, and clinical variables to predict HT occurrence. Although huge progress has been made, more individualized and precise HT prediction using simple and robust imaging predictors combining stroke onset time should be the future goal of development.

Hemorrhagic Transformation Following Childhood Cardioembolic Stroke Is Not Increased in Anticoagulated Patients

Objective: To characterize the risk of hemorrhagic transformation following cardioembolic stroke in childhood, and whether anticoagulation impacts that risk. Methods: Ninety-five children (1 month-18 years) with cardioembolic arterial ischemic stroke between January 1, 2009, and December 31, 2019, at 2 institutions were identified for retrospective chart review. Neuroimaging was reviewed to assess for hemorrhagic transformation. Results: There were 11 cases of hemorrhagic transformation; 8 occurred within 2 days of stroke diagnosis. Risk of hemorrhagic transformation did not differ in patients with and without anticoagulation use (15% vs 9%, estimated risk difference 5%; CI –9%, 19%). Stroke size did not predict hemorrhagic transformation (OR 1.004, 95% CI 0.997, 1.010). Risk of hemorrhagic transformation was higher in strokes that occurred in the inpatient compared with the outpatient setting (16% vs 6%). Conclusion: Hemorrhagic transformation occurred in 11% of pediatric cardioembolic ischemic stroke, usually within 2 days of stroke diagnosis, and was not associated with anticoagulation or stroke size.

High glycemic albumin representing prestroke glycemic variability is associated with hemorrhagic transformation in patients receiving intravenous thrombolysis

We evaluated the impact of prestroke glycemic variability estimated by glycated albumin (GA) on symptomatic hemorrhagic transformation (SHT) in patients with intravenous thrombolysis (IVT). Using a multicenter database, we consecutively enrolled acute ischemic stroke patients receiving IVT. A total of 378 patients were included in this study. Higher GA was defined as GA ≥ 16.0%. The primary outcome measure was SHT. Multivariate regression analysis and a receiver operating characteristic curve were used to assess risks and predictive ability for SHT. Among the 378 patients who were enrolled in this study, 27 patients (7.1%) had SHT as defined by the Safe Implementation of Thrombolysis in Stroke-Monitoring Study (SHTSITS). The rate of SHTSITS was higher in the higher GA group than in the lower GA group (18.0% vs. 1.6%, p < 0.001). A higher GA level (GA ≥ 16.0%) significantly increased the risk of SHTSITS (adjusted odds ratio [OR], [95% confidence interval, CI], 12.57 [3.08–41.54]) in the logistic regression analysis. The predictive ability of the GA level for SHTSITS was good (AUC [95% CI]: 0.83 [0.77–0.90], p < 0.001), and the cutoff value of GA in SHT was 16.3%. GA was a reliable predictor of SHT after IVT in acute ischemic stroke in this study.

STUDY OF SIGNIFICANCE OF PHASE MASK IMAGE IN ACUTE STROKE PATIENTS

Background: Phase images contains information regarding local susceptibility changes between the tissues, which can help measure the iron and other content which changes the local field. Typically, this information is ignored before looking at console. Susceptibility weighted imaging (SWI) is a magnetic resonance (MR) technique detects an early hemorrhagic transformation within the infarct to provide insight into cerebral hemodynamics following the stroke. Objective: Significance of “phase mask imaging in differentiation of hemorrhage and calcifications” in acute stroke patients. Methods: An observational non-interventional study carried out on 100 patients with stroke and headache symptoms. MRI Brain Stroke Profile with FLAIR, DWI, ADC, SWAN, and Phase mask sequences, done on 3T GE MRI scanner. Results: All patients underwent MRI study with SWI sequence. Of 183 cases, 33%(n=60) patients had microbleeds, 5%(n=10) patients had granulomas, 32%(n=58) patients had arterial thrombus with infarct, 11%(n=20) patients had falx calcifications, 11%(n=20) patients had intraparenchymal haemorrhage, and 8%(n=15) patients had infarcts with haemorrhagic transformation. The sensitivity of phase imaging in the detection of calcification was 90%. Conclusion: Phase mask imaging plays an important role to detect intracranial calcifications and chronic microbleeds. Phase mask imaging acts as a supplement tool in acute stroke patients, which guides further management.

Neuroinflammation in Cerebral Ischemia and Ischemia/Reperfusion Injuries: From Pathophysiology to Therapeutic Strategies

Its increasing incidence has led stroke to be the second leading cause of death worldwide. Despite significant advances in recanalization strategies, patients are still at risk for ischemia/reperfusion injuries in this pathophysiology, in which neuroinflammation is significantly involved. Research has shown that in the acute phase, neuroinflammatory cascades lead to apoptosis, disruption of the blood–brain barrier, cerebral edema, and hemorrhagic transformation, while in later stages, these pathways support tissue repair and functional recovery. The present review discusses the various cell types and the mechanisms through which neuroinflammation contributes to parenchymal injury and tissue repair, as well as therapeutic attempts made in vitro, in animal experiments, and in clinical trials which target neuroinflammation, highlighting future therapeutic perspectives.

Endovascular thrombectomy for acute ischemic stroke in patients with cancer: a propensity-matched analysis

BackgroundThere is a paucity of data and a belief that endovascular thrombectomy (EVT) has low efficacy for acute ischemic stroke (AIS) in patients with cancer. We aimed to critically compare the clinical outcomes of EVT for AIS in patients with and without cancer.MethodsRecords of all patients undergoing EVT for AIS between January 2015 and 2020 were screened for cancer at the time of EVT. Active cancer was defined as patients who were diagnosed with cancer and were undergoing or refused treatment for that cancer. Baseline modified Rankin Scale (mRS), age and sex were used in a 1:5 propensity score matching ratio. After matching we evaluated for any change in the National Institutes of Health Stroke Scale (NIHSS) from baseline to discharge, hemorrhagic transformation (HT), and 90-day mRS and mortality.ResultsThere were 19 patients with cancer and 95 matched controls. The mean±SD age was 70.89±11.16 years, and 17 (89.47%) were female. The baseline NIHSS was 22±7.5 and baseline mRS was 1 (IQR 1). There was no significant difference in change in baseline to discharge NIHSS, 90-day mRS or mortality; 90-day mRS 0–2 was 45.2% in the non-cancer group versus 46.7% in cancer group (p=0.54). HT was significantly higher in patients with cancer (57.89% vs 6.49%, p<0.001).ConclusionsIn propensity matched analysis of patients undergoing EVT for AIS with and without cancer, 90-day functional outcomes and mortality were similar. However, there was a significantly higher rate of HT in cancer patients.

Clinical and Imaging Indicators of Hemorrhagic Transformation in Acute Ischemic Stroke After Endovascular Thrombectomy

Background and Purpose: Prior studies have investigated the clinical and imaging factors for hemorrhagic transformation (HT), especially symptomatic intracranial hemorrhage (sICH); however, whether alteplase increases the risk of HT after endovascular thrombectomy (EVT) is unknown. This study aimed to assess clinical and imaging features associated with HT, sICH, and parenchymal hematoma (PH) in patients with acute ischemic stroke after EVT, with and without intravenous alteplase in DIRECT-MT (Direct Intraarterial Thrombectomy to Revascularize Acute Ischemic Stroke Patients with Large Vessel Occlusion Efficiently in Chinese Tertiary Hospitals: a Multicenter Randomized Clinical Trial). Methods: The DIRECT-MT trial is a randomized trial of EVT alone versus intravenous thrombolysis combined with EVT. HT, sICH, and PH was evaluated on follow-up computed tomography. Multivariable ordinal logistic regression analysis was used to test the association of stepwise selected determinants with HT, sICH, and PH. Results: In total, 633 patients were analyzed; 261 (41.2%) had HT; 34 (5.4%) had sICH; and 85 (13.4%) had PH. The median age was 69, and 56.7% were men. The median National Institutes of Health Stroke Scale score was 18, and 320 patients were in combination-therapy group. Symptomatic intracranial hemorrhage was associated with higher baseline National Institutes of Health Stroke Scale score (adjusted odds ratio [OR], 1.06 [95% CI, 1.10–1.12]) and higher glucose level at hospital arrival (adjusted OR, 1.14 [95% CI, 1.00–1.29]). No association was found between alteplase treatment and HT, sICH, or PH. The independent predictor of sICH was higher baseline National Institutes of Health Stroke Scale score (adjusted OR, 1.09 [95% CI, 1.01–1.18]) in EVT alone group, and history of anticoagulant drugs (adjusted OR, 3.75 [95% CI, 1.07–13.06]), higher glucose level at hospital arrival (adjusted OR, 1.19 [95% CI, 1.03–1.38]), >3 passes of device (adjusted OR, 4.42 [95% CI, 1.36–14.32]) in combination-therapy group. Conclusions: In DIRECT-MT, independent predictors of sICH were baseline National Institutes of Health Stroke Scale score and glucose level at hospital arrival. Alteplase treatment did not increase the risk of HT, sICH, or PH after EVT. The independent predictor of sICH was different in EVT alone group and combination-therapy group. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT03469206.

A Review of Risk Factors and Predictors for Hemorrhagic Transformation in Patients with Acute Ischemic Stroke

Acute ischemic strokes (AIS) and hemorrhagic strokes lead to disabling neuropsychiatric and cognitive deficits. A serious and fatal complication of AIS is the occurrence of hemorrhagic transformation (HT). HT is cerebral bleeding that occurs after an ischemic event in the infarcted areas. This review summarises how specific risk factors such as demographic factors like age, gender, and race/ethnicity, comorbidities including essential hypertension, atrial fibrillation, diabetes mellitus, congestive heart failure, and ischemic heart disease along with predictors like higher NIHSS score, larger infarction size, cardioembolic strokes, systolic blood pressure/pulse pressure variability, higher plasma glucose levels, and higher body temperature during ischemic event, lower low-density lipoprotein and total cholesterol, early ischemic changes on imaging modalities, and some rare causes make an individual more susceptible to developing HT. We also discuss few other risk factors such as the role of blood-brain barrier, increased arterial stiffness, and globulin levels in patients postreperfusion using thrombolysis and mechanical thrombectomy. In addition, we discuss the implications of dual antiplatelet therapy and the length of treatment in reference to the incidence of developing HT. Current research into inflammatory mediators and biomarkers such as Cyclooxygenase-2, matrix metalloproteinases, and soluble ST2 and their potential role as treatment options for HT is also briefly discussed. Finally, this review calls for more research into use of dual antiplatelet and the timing of antiplatelet and anticoagulant use in reference to hemorrhagic transformation.

Young Stroke Secondary To Fibromuscular Dysplasia Causing Carotid Artery Dissection

Background: Fibromuscular dysplasia (FMD) is a rare, medium-sized arteriopathy affecting less than 7% of the population. It affects predominantly young women of childbearing age. Stroke caused by fibromuscular dysplasia of the carotid artery is uncommon and reported to range between 0.6% by angiography and 1.1% by autopsy. Case Presentation: A 35-year-old mother of two children, previously well, was admitted to our hospital with right-sided spastic hemiparesis with upper motor neuron type facial nerve palsy. Non-contrast CT (NCCT) brain on admission revealed left-sided middle cerebral arterial territory infarction with possible hemorrhagic transformation with midline shift. She had progressive neurological features where NCCT brain in 24 hours showed an increase in the size of the hemorrhage. Magnetic resonance imaging (MRI) of the brain, including angiogram of neck vessels, revealed acute dissection of the left internal carotid artery with acute thrombosis, left frontoparietal hemorrhagic infarction, and the constellation of MRI showed features suggestive of left cervico-cranial fibromuscular dysplasia complicated by acute internal carotid artery dissection. She was started on low-dose aspirin, and 40 mg of atorvastatin and anticoagulants were not started because of the bleeding risk as she had a hemorrhagic transformation infarction. She was discharged and referred for inward physiotherapy and planned to repeat the MRI brain with the neck vessel angiogram in three weeks and arranged digital subtraction angiography in three months. Unfortunately, she was lost for follow-up.Conclusion: Detailed evaluation of the young patients with ischaemic stroke is helpful to diagnose rare diseases such as FMD involving carotid arteries leading to a better treatment choice between anticoagulation vs. antiplatelet therapy.