Systolic Blood Pressure Variability is Associated with Severe Hemorrhagic Transformation in the Early Stage After Thrombolysis

Association between oral microbial nitrate metabolism and poor prognosis in acute ischemic stroke patients with a history of hypertension

Background

Oral microbes mediate the production of nitric oxide (NO) through the denitrification pathway. This study aimed to investigate the association between oral microbial nitrate metabolism and prognosis in acute ischemic stroke (AIS) patients.

Methods

This prospective, observational, single-center cohort study included 124 AIS patients admitted within 24 hours of symptom onset, with 24-hour ambulatory blood pressure data. Oral swabs were collected within 24 hours. Hypertensive AIS patients were stratified by the coefficient of variation (CV) of 24-hour systolic blood pressure. Microbial composition was analyzed using LEfSe and PICRUSt2 for bacterial and functional pathway identification.

Results

Significant differences in oral microbiota composition were observed between hypertensive AIS patients with varying CVs. Lower CV groups showed enrichment of nitrate-reducing bacteria and "Denitrification, nitrate => nitrogen" pathways. The TAX score of oral nitrate-reducing bacteria, derived from LASSO modeling, independently correlated with 90-day modified Rankin Scale scores, serving as an independent risk factor for poor prognosis. Mediation analyses suggested indirect that the TAX score not only directly influences outcomes but also indirectly affects them by modulating 24-hour systolic blood pressure CV.

Conclusions

AIS patients with comorbid hypertension and higher systolic blood pressure CV exhibited reduced oral nitrate-reducing bacteria, potentially worsening outcomes.

Blood Pressure Variability in Acute Stroke: A Narrative Review

The management of blood pressure variability (BPV) in acute stroke presents a complex challenge with profound implications for patient outcomes. This narrative review examines the role of BPV across various stages of acute stroke care, highlighting its impact on treatment strategies and prognostic considerations. In the prehospital setting, while guidelines lack specific recommendations for BP management, emerging evidence suggests a potential link between BPV and outcomes. Among ischaemic stroke patients who are ineligible for reperfusion therapies, BPV independently influences functional outcomes, emphasising the need for individualised approaches to BP control. During intravenous thrombolysis and endovascular therapy, the intricate interplay between BP levels, recanalisation status, and BPV is evident. Striking a balance between aggressive BP lowering and avoiding hypoperfusion-related complications is essential. Intracerebral haemorrhage management is further complicated by BPV, which emerges as a predictor of mortality and disability, necessitating nuanced BP management strategies. Finally, among patients with acute subarachnoid haemorrhage, increased BPV may be correlated with a rebleeding risk and worse outcomes, emphasizing the need for BPV monitoring in this population. Integration of BPV assessment into clinical practice and research protocols is crucial for refining treatment strategies that are tailored to individual patient needs. Future studies should explore novel interventions targeting BPV modulation to optimise stroke care outcomes.

The impact of blood pressure variability on the development of parenchymal hematoma in acute cerebral infarction with atrial fibrillation

Although blood pressure variability (BPV) and reperfusion are associated with parenchymal hematoma (PH) after stroke, the relationship between BPV and PH in atrial fibrillation (AF) patients who are at risk of reperfusion injury with frequent spontaneous recanalization is unknown. This study aimed to investigate whether BPV within the first 48 h is associated with PH within 72 h in patients with AF and stroke in terms of major vessel occlusion status. A total of 131 patients with AF that were admitted within 24 h after stroke onset were enrolled. PH was defined as a confluent hemorrhage with mass effect. The maximum (max), minimum (min), and average blood pressure (BP) during the first 48 h after admission were calculated. BPV was analyzed by using range between maximum and minimum (max-min), successive variation (SV), standard deviation (SD), and coefficient of variation (CV). All parameters were applied for systemic (SBP), diastolic (DBP), and pulse pressure (PP). After adjusting for confounding variables, various BPV parameters were associated with PH, including SBPmax (p = 0.0426), SBPSV (p = 0.0006), DBPmax-min (p = 0.0437), DBPSV (p = 0.0358), DBPSD (p = 0.0393), PPmax-min (p = 0.0478), PPSV (p < 0.0001), PPSD (p = 0.0034), and PPCV (p = 0.0120). The relationship remained significant in patients with a patent major vessel responsible for infarction but not in patients with an occluded major vessel. In conclusion, this study revealed that high BPV was associated with PH in patients with AF and acute stroke, particularly for those with a patent major vessel. The control of BP and BPV after stroke may be considered in patients with AF.

Anesthetic management of endovascular neurosurgical procedures in acute ischemic stroke patients: A systematic review of meta-analyses

Restoration of cerebral circulation in the ischemic area is the most critical treatment task for reducing irreversible neuronal injury in ischemic stroke patients. The recanalización of appropriately selected patients became indispensable for improving clinical outcomes and resulted in the widespread revascularization techniques. There is no clear answer as to which anesthetic modality to use in ischemic stroke patients undergoing neuro-endovascular procedures. The purpose of this systematic review is to conduct a qualitative analysis of systematic reviews and meta-analyses (RSs & MAs) comparing general anesthesia and non-general anesthesia methods for cerebral endovascular interventions in acute ischemic stroke patients. We developed a protocol with the inclusion and exclusion criteria for matched publications and conducted a literature search in PubMed and Google Scholar. The literature search yielded 52 potential publications. Ten relevant RSs & MAs were included and analysed in this review. The decision about which anesthesia method to use for endovascular procedures in managing acute ischemic stroke patients should be made based on the patient's personal characteristics, pathophysiological phenotypes, clinical characteristics, and institutional experience.

Early Hemorrhagic Transformation after Reperfusion Therapy in Patients with Acute Ischemic Stroke: Analysis of Risk Factors and Predictors

Background: The standard reperfusion therapy for acute ischemic stroke (AIS) is considered to be thrombolysis, but its application is limited by the high risk of hemorrhagic transformation (HT). This study aimed to analyze risk factors and predictors of early HT after reperfusion therapy (intravenous thrombolysis or mechanical thrombectomy). Material and methods: Patients with acute ischemic stroke who developed HT in the first 24 h after receiving rtPA thrombolysis or performing mechanical thrombectomy were retrospectively reviewed. They were divided into two groups, respectively, the early-HT group and the without-early-HT group based on cranial computed tomography performed at 24 h, regardless of the type of hemorrhagic transformation. Results: A total of 211 consecutive patients were enrolled in this study. Among these patients, 20.37% (n = 43; age: median 70.00 years; 51.2% males) had early HT. Multivariate analysis of independent risk factors associated with early HT found that male gender increased the risk by 2.7-fold, the presence of baseline high blood pressure by 2.4-fold, and high glycemic values by 1.2-fold. Higher values of NIHSS at 24 h increased the risk of hemorrhagic transformation by 1.18-fold, while higher values of ASPECTS at 24 h decreased the risk of hemorrhagic transformation by 0.6-fold. Conclusions: In our study, male gender, baseline high blood pressure, and high glycemic values, along with higher values of NIHSS were associated with the increased risk of early HT. Furthermore, the identification of early-HT predictors is critical in patients with AIS for the clinical outcome after reperfusion therapy. Predictive models to be used in the future to select more careful patients with a low risk of early HT need to be developed in order to minimize the impact of HT associated with reperfusion techniques.

The 2020 Taiwan Stroke Society guidelines for blood pressure control at the acute stage of ischemic stroke

The 2020 Taiwan Stroke Society (TSS) guidelines for blood pressure (BP) control related to ischemic stroke update the 2015 TSS BP guidelines. The early management of acute ischemic stroke has evolved rapidly in the previous two decades. Since the publication of the previous version of the TSS BP guidelines, many studies have addressed BP management in ischemic stroke. Particularly, several successful endovascular thrombectomy (EVT) trials published in 2015 led to a new era of acute treatment for ischemic stroke. With the ever-increasing use of EVT, evidence-based guidelines for ideal BP management during and after EVT are urgently needed. Consequently, the 2020 guidelines are updating and providing recommendations on BP control for the treatment and prevention of ischemic stroke based on new evidence. The present study encompasses the most important chapter of the 2020 Taiwan BP guidelines: BP control at the acute stage of ischemic stroke. We incorporated the most updated evidence regarding BP control at the acute stage of ischemic stroke in patients receiving or not receiving acute reperfusion therapy and provided specific recommendations for different treatment subgroups accordingly.

Machine Learning-Based Model for Prediction of Hemorrhage Transformation in Acute Ischemic Stroke After Alteplase

Hemorrhage transformation (HT) is the most dreaded complication of intravenous thrombolysis (IVT) in acute ischemic stroke (AIS). The prediction of HT after IVT is important in the treatment decision-making for AIS. We designed and compared different machine learning methods, capable of predicting HT in AIS after IVT. A total of 345 AIS patients who received intravenous alteplase between January 2016 and June 2021 were enrolled in this retrospective study. The demographic characteristics, clinical condition, biochemical data, and neuroimaging variables were included for analysis. HT was confirmed by head computed tomography (CT) or magnetic resonance imaging (MRI) within 48 h after IVT. Based on the neuroimaging results, all of the patients were divided into the non-HT group and the HT group. Then, the variables were applied in logistic regression (LR) and random forest (RF) algorithms to establish HT prediction models. To evaluate the accuracy of the machine learning models, the models were compared to several of the common scales used in clinics, including the multicenter stroke survey (MSS) score, safe implementation of treatments in stroke (SITS) score, and SEDAN score. The performance of these prediction models was evaluated using the receiver operating characteristic (ROC) curve (AUC). Forty-five patients had HT (13.0%) within 48 h after IVT. The ROC curve results showed that the AUCs of HT that were predicted by the RF model, LR model, MSS, SITS, and SEDAN scales after IVT were 0.795 (95% CI, 0.647–0.944), 0.703 (95% CI, 0.515–0.892), 0.657 (95% CI, 0.574–0.741), 0.660 (95% CI, 0.580–0.740) and 0.655 (95% CI, 0.571–0.739), respectively. The RF model performed better than the other models and scales. The top four most influential factors in the RF importance matrix plot were triglyceride, Lpa, the baseline NIHSS, and hemoglobin. The SHapley Additive exPlanation values made the RF prediction model clinically interpretable. In this study, an RF machine learning method was successfully established to predict HT in AIS patients after intravenous alteplase, which the sensitivity was 66.7%, and the specificity was 80.7%.

Blood Pressure Variability After Cerebrovascular Events—A Possible New Therapeutic Target: A Narrative Review

Blood pressure variability, the variation of blood pressure during a certain period, results from the interaction of hemodynamic, neuronal, humoral, behavioral, and environmental factors. Cerebral autoregulation is impaired in acute cerebrovascular disease. In these patients, increased blood pressure variability may provoke or exacerbate secondary brain injury. In fact, available data showed that increased Blood pressure variability is associated with worse outcomes after acute ischemic stroke, intracerebral hemorrhage, and aneurysmal subarachnoid hemorrhage. Consequently, blood pressure variability may represent a usual modifiable therapeutic target. This concept this particularly attractive because reduction of blood pressure variability can be feasible in regions with lower resources and can be applicable to patients with various forms of acute stroke. Prospective studies are needed to further clarify the relationship between blood pressure variability and secondary brain damage, and the determinants of blood pressure variability in different clinical populations. Ultimately, cerebrovascular disease-specific randomized controlled trials aimed at reducing blood pressure variability, irrespective of the absolute blood pressure values, are needed to determine if reduction of blood pressure variability can improve outcomes in patients with acute cerebrovascular disease.

Detrimental effect of increased blood pressure variability on clinical outcome in acute ischemic stroke treated with reperfusion therapy: a case control study

Background

Blood pressure variability (BPV) is related to clinical outcome in acute ischemic stroke (AIS) treated with reperfusion therapy, but still is not included in clinical practice. This study aims to associate BPV during the first week of AIS with the outcome at three months.

Methods

We included 236 AIS patients treated with reperfusion therapy, and then divided them into good outcome and poor outcome groups. BPV measurements, including standard deviation, coefficient of variation, average real variability (ARV), and range, were recorded at stages of 2 h, 24 h, and 7 days after reperfusion therapy, respectively. These measurements were compared between the two groups. Then, ROC curve analysis examined the ability of BPV measurements in differentiating good and poor outcome groups; logistic regression analysis detected variables associated with clinical outcome in all subjects.

Results

The good outcome group exhibited significantly less BPV at all stages relative to the poor outcome group. The BPV measurements exhibited the potential to differentiate the two groups by the ROC curve analysis, especially for those at the 24-h stage. Higher ARV of diastolic BP and higher range of systolic BP at the 24-h stage, together with greater disease severity at baseline, were associated with poor clinical outcome.

Conclusions

Greater BPV during the first week of AIS is associated with poor outcome for the patients treated with reperfusion therapy. The BPV measurements play an important role in modulating clinical outcome, and have the potential to be included in future AIS guidelines.

Integrative physiological assessment of cerebral hemodynamics and metabolism in acute ischemic stroke

Restoring perfusion to ischemic tissue is the primary goal of acute ischemic stroke care, yet only a small portion of patients receive reperfusion treatment. Since blood pressure (BP) is an important determinant of cerebral perfusion, effective BP management could facilitate reperfusion. But how BP should be managed in very early phase of ischemic stroke remains a contentious issue, due to the lack of clear evidence. Given the complex relationship between BP and cerebral blood flow (CBF)-termed cerebral autoregulation (CA)-bedside monitoring of cerebral perfusion and oxygenation could help guide BP management, thereby improve stroke patient outcome. The aim of INFOMATAS is to 'identify novel therapeutic targets for treatment and management in acute ischemic stroke'. In this review, we identify novel physiological parameters which could be used to guide BP management in acute stroke, and explore methodologies for monitoring them at the bedside. We outline the challenges in translating these potential prognostic markers into clinical use.

Comparison of intermittent versus continuous infusion antihypertensives in acute ischemic stroke

BACKGROUND

The optimal approach to blood pressure (BP) management in acute ischemic stroke remains unclear. The purpose of this study was to determine if an intermittent (labetalol or hydralazine) or continuous infusion (nicardipine or clevidipine) antihypertensive strategy facilitated timelier alteplase administration.

METHODS

Patients ≥18 years who presented to the emergency department (ED) between September 1, 2013 and August 31, 2020, received alteplase for acute ischemic stroke, and required BP management with an intravenous antihypertensive were included in this multicenter, retrospective cohort study. Exclusion criteria were initial administration of a non-study antihypertensive, initial study antihypertensive administration >2 hours prior to or any time following alteplase, or receipt of both an intermittent and continuous infusion antihypertensive prior to alteplase. The primary endpoint was the time from ED presentation to alteplase administration.

RESULTS

During the study period, 122 patients received an intermittent antihypertensive and 57 patients received a continuous infusion antihypertensive. The median door-to-needle time was 53 minutes for patients who received an intermittent antihypertensive compared to 57 minutes for those who received a continuous infusion antihypertensive (p=0.17). Secondarily, the proportion of patients who achieved the BP target <185/110 mmHg within 15 minutes of initial antihypertensive administration and the incidence of adverse events were similar between treatment groups. In cost analysis, intermittent antihypertensives were less expensive than continuous infusion antihypertensives ($2.20 vs. $71.40).

CONCLUSIONS

Among patients with acute ischemic stroke and uncontrolled BP, the initial use of an intermittent or continuous infusion antihypertensive did not significantly impact the time to alteplase administration.

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.

Development and Validation of a Predictive Model for Spontaneous Hemorrhagic Transformation After Ischemic Stroke

Background: Hemorrhagic transformation (HT) after reperfusion therapy for acute ischemic stroke (AIS) has been well studied; however, there is scarce research focusing on spontaneous HT (sHT). Spontaneous HT is no less important with a relatively high incidence and could be associated with neurological worsening. We aimed to develop and validate a simple and practical model to predict sHT after AIS (SHAIS) and compared the predictive value of the SHAIS score against the models of post-Reperfusion HT for sHT.

Methods: Patients with AIS admitted within 24 h of onset were prospectively screened to develop and validate the SHAIS score. The primary outcome was sHT during hospitalization (within 30 days after onset), and the secondary outcomes were symptomatic sHT and parenchymal hematoma (PH). Clinical information, laboratory, and neuroimaging data were screened to construct the SHAIS score. We selected six commonly used scales for predicting HT after reperfusion therapy and compared their predictive ability for sHT with the SHAIS score using Delong's test.

Results: The derivation cohort included 539 patients (mean age, 68.1 years; men, 61.4%), of whom 91 (16.9%) patients developed sHT with 25.3% (23/91) being symptomatic sHT and 62.6% (57/91) being PH. Five variables (atrial fibrillation, NIHSS score ≥ 10, hypodensity > 1/3 of middle cerebral artery territory, hyperdense artery sign, and anterior circulation infarction) composed the SHAIS score, which ranged from 0 to 11 points. The area under the receiver-operating characteristic curve (AUC) was 0.86 (95% CI 0.82–0.91, p < 0.001) for the overall sHT, 0.85 (95% CI 0.76–0.92, p < 0.001) for symptomatic sHT, and 0.89 (95% CI 0.85–0.94, p < 0.001) for PH. No evidence of miscalibration of the SHAIS score was found to predict the overall sHT (p = 0.19), symptomatic sHT (p = 0.44), and PH (p = 0.22). The internal (n = 245) and external validation cohorts (n = 200) depicted similar predictive performance compared to the derivation cohort. The SHAIS score had a higher AUC to predict sHT than any of the six pre-Existing models (p < 0.05).

Conclusions: The SHAIS score provides an easy-to-use model to predict sHT, which could help providers with decision-making about treatments with high bleeding risk, and to counsel patients and families on the baseline risk of HT, aligning expectations with probable outcomes.

Hemorrhagic Transformation in Ischemic Stroke and the Role of Inflammation

Hemorrhagic transformation (HT) is a common complication in patients with acute ischemic stroke. It occurs when peripheral blood extravasates across a disrupted blood brain barrier (BBB) into the brain following ischemic stroke. Preventing HT is important as it worsens stroke outcome and increases mortality. Factors associated with increased risk of HT include stroke severity, reperfusion therapy (thrombolysis and thrombectomy), hypertension, hyperglycemia, and age. Inflammation and the immune system are important contributors to BBB disruption and HT and are associated with many of the risk factors for HT. In this review, we present the relationship of inflammation and immune activation to HT in the context of reperfusion therapy, hypertension, hyperglycemia, and age. Differences in inflammatory pathways relating to HT are discussed. The role of inflammation to stratify the risk of HT and therapies targeting the immune system to reduce the risk of HT are presented.

Blood pressure variability and outcomes after mechanical thrombectomy based on the recanalization and collateral status

BACKGROUND

Blood pressure (BP), recanalization status, and collateral circulation are important factors for cerebral autoregulation after stroke. We aimed to investigate the association of various BP variability (BPV) parameters with clinical outcomes after mechanical thrombectomy (MT) according to recanalization and collateral status.

METHODS

We included 502 consecutive patients who underwent MT due to anterior circulation large vessel occlusion stroke at three comprehensive stroke centers. BPV parameters were standard deviation (SD), maximum/minimum BP, coefficient of variation (CV) and successive variation (SV). The clinical outcomes included 90-day functional outcome assessed by modified Rankin Scale score and symptomatic intracranial hemorrhage (sICH).

RESULTS

Among the included patients, 219 (43.6%) achieved good functional outcomes and 59 (11.8%) developed sICH. After adjusting for confounders, higher systolic BP (SBP) variability [CV (odds ratio (OR), 1.089, p = 0.035), SV (OR, 1.082, p = 0.004). and SD (OR, 1.074, p = 0.027)] was associated with a lower likelihood of a favorable outcome. In addition, higher SBP [CV (OR, 1.156, p = 0.001) and SD (OR, 1.118, p = 0.001)] were significantly associated with increased odds of sICH. Moreover, the relationship between BPV and the outcomes depended on recanalization status. However, regardless of collateral status, a higher BPV after MT was associated with worse outcomes.

CONCLUSIONS

Higher SBP SD and CV during the first 24 h after MT was a powerful predictor of worse clinical outcomes, regardless of the collateral status. However, the effects of BPV on outcomes were more substantial among patients with successful reperfusion.

Management of Elevated Blood Pressure After Stroke Thrombectomy for Anterior Circulation

Thrombectomy is superior to intravenous thrombolysis for patients with large vessel occlusion in acute ischemic stroke, but nearly half of the patients still experience poor functional outcomes. Elevated blood pressure (BP) is widely observed in acute ischemic stroke, and BP may be one of the modifiable parameters that can potentially influence the outcomes; however, only observational studies exist to support current guidelines, and the recommended range for BP after thrombectomy is too wide to meet the clinical requirement. Randomized controlled trials are therefore needed to better understand the relationship between BP and outcomes after thrombectomy. In this review, we introduce the current management of BP after thrombectomy and several aspects of postthrombectomy BP management that should be resolved in future clinical trials.

Association of Blood Pressure at Successful Recanalization and Parenchymal Hemorrhage After Mechanical Thrombectomy With General Anesthesia

Background: This study aims to investigate the association between blood pressure (BP) at the time of recanalization and hemorrhagic transformation in large vessel occlusion (LVO) patients following mechanical thrombectomy (MT) with general anesthesia.

Methods: We retrospectively reviewed our data base for patients with acute ischemic stroke acute ischemic stroke (AIS) who received MT between January 2018 and December 2019. The BP at two adjacent time points immediately after successful recanalization was recorded for subsequent calculation of mean BP (BP_mean), maximum BP (BP_max), minimum BP (BP_min), range of BP (BP_range), and standard deviation of SP (BP_SD). Hemorrhagic transformation was identified on 24-h computerized tomography images according to the European Cooperative Acute Stroke Study (ECASS) III trial. We used binary logistic regression analysis to investigate the association of BP parameters and the incidence of parenchymal hemorrhage (PH) and PH-2.

Results: A total of 124 patients with anterior circulation LVO were finally included for analyses. After controlling for intravenous thrombolysis, procedure duration of mechanical thrombectomy, baseline National institutes of Health Stroke Scale (NIHSS), baseline ASPECTS, and number of device passes, the results showed that every increment of 10 mmHg in SBP_range (OR 1.559; 95% CI 1.027–2.365; P = 0.037) and SBP_SD (OR 1.998; 95% CI 1.017–3.925; P = 0.045) were independently associated with PH. After adjustment for intravenous thrombolysis, procedure duration of mechanical thrombectomy, baseline NIHSS, the results showed that every increment of 10 mmHg in SBP_mean (OR 1.973; 95% CI 1.190–3.271; P = 0.008), SBP_max (OR 1.838; 95% CI 1.199 to 2.815; P = 0.005), SBP_range (OR 1.908; 95% CI 1.161–3.136; P = 0.011) and SBP_SD (OR 2.573; 95% CI 1.170–5.675; P = 0.019) were independently associated with PH-2.

Conclusion: Patients with higher systolic BP and variability at the time of successful recanalization were more likely to have PH-2 in LVO patients following MT with general anesthesia.

Effects of Early Changes in Blood Pressure During Intravenous Thrombolysis on the Prognosis of Acute Ischemic Stroke Patients

Background: Intravenous thrombolysis (IVT) therapy is currently one of the best medical treatments available for patients with acute ischemic stroke. Studies have shown that blood pressure (BP) changes in patients treated with IVT are significantly correlated with prognosis. Objective: Our study aimed to determine the relationship between BP changes during recombinant tissue plasminogen activator (rt-PA) infusion and the 3-month prognosis evaluated using the modified Rankin Scale (mRS) and determine the factors influencing BP changes during rt-PA infusion. Methods: Consecutive patients who were treated with IVT and admitted to our stroke center between May 2015 and October 2017 were analyzed retrospectively. Patients were divided into two groups according to their 3-month prognosis status: patients with mRS ≤ 2 were defined as "favorable outcome group" and those with mRS ≥ 3 as "unfavorable outcome group". First, the factors affecting prognosis after thrombolysis were analyzed. Second, we analyzed the relationship between BP and the prognosis. BP was taken before and at regular intervals of 15 min during the rt-PA infusion (1 h). The average value of BP during thrombolysis was calculated and compared to the baseline BP. BP decrease was defined as the difference between the baseline BP and the average BP, provided it was greater than 0 mmHg. Third, univariate and multivariate analyses were performed to identify factors that may contribute to BP decrease. Results: In total, 458 patients were included. Patients with a lower baseline National Institute of Health Stroke Scale (NIHSS) score (8.25 ± 5.57 vs. 13.51 ± 7.42, P < 0.001), a higher Alberta Stroke Program Early CT Score (ASPECTS; 8.65 ± 1.82 vs. 8.13 ± 2.00, P = 0.005), decreased BP during thrombolysis (69.4% vs. 59.8%, P = 0.037), and steady BP (SD < 10 mmHg) were more likely to have a favorable outcome (73.9% vs. 60.6%, P = 0.019). High baseline BP (OR > 1), hypertension history (OR < 1), and baseline ASPECTS (OR > 1) were independent factors of BP change during thrombolysis. Conclusion: Patients with decreased or steady BP during thrombolysis were more likely to have a favorable outcome. Baseline ASPECTS, baseline NIHSS score, and hypertension history influenced BP changes during thrombolysis.

Hemorrhagic Transformation After Tissue Plasminogen Activator Treatment in Acute Ischemic Stroke

Hemorrhagic transformation (HT) is a common complication after thrombolysis with recombinant tissue-type plasminogen activator (rt-PA) in ischemic stroke. In this article, recent research progress of HT in vivo and in vitro studies was reviewed. We have discussed new potential mechanisms and possible experimental models of HT development, as well as possible biomarkers and treatment methods. Meanwhile, we compared and analyzed rodent models, large animal models and in vitro BBB models of HT, and the limitations of these models were discussed. The molecular mechanism of HT was investigated in terms of BBB disruption, rt-PA neurotoxicity and the effect of neuroinflammation, matrix metalloproteinases, reactive oxygen species. The clinical features to predict HT were represented including blood biomarkers and clinical factors. Recent progress in neuroprotective strategies to improve HT after stroke treated with rt-PA is outlined. Further efforts need to be made to reduce the risk of HT after rt-PA therapy and improve the clinical prognosis of patients with ischemic stroke.

Dietary nitrate reduces blood pressure and cerebral artery velocity fluctuations and improves cerebral autoregulation in transient ischemic attack patients

We found dietary nitrate supplementation reduced blood pressure and brain blood flow fluctuations and improved the relationship between blood pressure and brain blood flow in transient ischemic attack patients. Meanwhile, dietary nitrate had no effects on the brain blood vessels’ response to CO2. We attribute the improved brain blood flow stability to the improved myogenic control of blood pressure with dietary nitrate. Our findings indicate that dietary nitrate could be an effective strategy for stabilizing blood pressure and brain blood flow following transient ischemic attack.

Relationship between saline infusion and blood pressure variability in non-critically patients with hypertension: A retrospective study

Saline is a commonly used intravenous solvent, however, its excessive infusion may increase drug-induced sodium intake. To investigate the effects of saline infusion on blood pressure variability (BPV) in patients with hypertension, a retrospective study was performed in 1010 patients with hypertension. The patients who received saline infusion before surgery for continuous 3 to 5 days were divided into 2 groups according to the saline infusion volume during the hospitalization, which are >500 mL per day group and <500 mL per day group. The overall incidence of abnormal BPV was 11.58%. As for the incidence of abnormal BPV in the <500 mL per day group with 698 patients was 9.17%, while that in the >500 mL per day group with 312 patients was as high as 16.99%. Additionally, >500 mL of daily saline infusion for continuous 3 to 5 days (P for trend = .004, odds ratio [OR] = 1.911, 95% confidence interval [CI] for OR 1.226-2.977), medical history of diabetes mellitus (P < .001, OR = 4.856, 95% CI for OR 3.118-7.563) and cardiovascular diseases (P < .001, OR = 2.498, 95% CI for OR 1.549-4.029) may be risk factors of abnormal BPV; while anti-hypertensive therapy with diuretics (P < .001, OR = 0.055, 95% CI for OR 0.024-0.125) may be the protective factor. Our study suggests that >500 mL of daily saline infusion for continuous 3 to 5 days may have disadvantages in the blood pressure control for hypertensive patients, especially for the patients with diabetes mellitus and cardiovascular diseases.

Reperfusion Into Severely Damaged Brain Tissue Is Associated With Occurrence of Parenchymal Hemorrhage for Acute Ischemic Stroke

Background and Purpose: This study aims to quantify the reperfusion status within severely damaged brain tissue and to evaluate its relationship with high grade of hemorrhagic transformation (HT).

Methods: Pseudo-continuous ASL was performed along with DWI in 102 patients within 24 h post-treatments. The infarction core was identified using ADC values <550 × 10⁻⁶ mm²/s. CBF within the infarction core and its contralateral counterpart were acquired. CBF at the 25th, median, and 75th percentiles of the contralateral counterpart were used as thresholds and the ASL reperfusion volume above the threshold was labeled as vol-25, -50, and -75, respectively. Recanalization was defined according to Thrombolysis in Myocardial Infarction (TIMI) criteria.

Results: Quantified reperfusion within the infarction core differed significantly in patients with complete and incomplete recanalization. In the ROC analysis for the prediction of parenchymal hematoma (PH), ASL reperfusion vol-25 had the highest area under the curve (AUC) when compared with ASL vol-50 and ASL vol-75. ASL reperfusion vol-25 had significantly higher AUC compared with ADC threshold volume in the prediction of PH (0.783 vs. 0.685, P = 0.0036) and PH-2 (0.844 vs. 0.754, P = 0.0035). In stepwise multivariate logistic regression analysis, only ASL reperfusion vol-25 emerged as an independent predictor of PH (OR = 3.51, 95% CI: 1.65–7.45, P < 0.001) and PH-2 (OR = 2.32, 95% CI: 1.13–4.76, P = 0.022).

Conclusions: Increased reperfusion volume within severely damaged brain tissue is associated with the occurrence of higher grade of HT.

Effects of Baseline Systolic Blood Pressure on Outcome in Ischemic Stroke Patients With Intravenous Thrombolysis Therapy: A Systematic Review and Meta-Analysis

BACKGROUND

Baseline systolic blood pressure (SBP) is an important parameter that can significantly influence the outcome in ischemic stroke patients who received intravenous thrombolysis, but the target baseline SBP for optimal outcome is uncertain. This study aimed to assess the relationship between baseline SBP and outcome.

MATERIALS AND METHODS

Studies that evaluated the association between the baseline SBP and the outcome of patients undergoing thrombolytic therapy were sought. Data were extracted according to a predefined data extraction form and then analyzed by STATA 12.0 software. The primary endpoint was the occurrence of good outcomes measured by a modified Rankin Scale score at 3 months, while the secondary endpoint was the occurrence of intracranial hemorrhage and death.

RESULTS

Eleven studies involving a total of 33,263 patients were included. Pooled data suggested that the odds of good outcome was decreased by 7% per 10 mm Hg increase in baseline SBP (odds ratio=0.93; 95% confidence interval: 0.91-0.94; P<0.001). Patients with higher baseline SBP were more likely to have intracranial hemorrhage (odds ratio=1.12 per 10 mm Hg increase; 95% confidence interval: 1.08-1.16, P<0.001).

CONCLUSIONS

This study suggested that lower baseline SBP may be positively associated with a greater chance of good outcome and less chance of intracranial hemorrhage. However, this effect was reliable only when the baseline SBP was within a certain range, which has not been explicitly stated. Therefore, more well-designed studies are needed to define the optimal baseline SBP.

High Neutrophil-to-Lymphocyte Ratio Predicts Hemorrhagic Transformation in Acute Ischemic Stroke Patients Treated with Intravenous Thrombolysis

BACKGROUND

The relationship between the neutrophil-to-lymphocyte ratio (NLR) and hemorrhagic transformation (HT) in acute ischemic stroke (AIS) treated with intravenous thrombolysis (IVT) remains unclear. This study assessed whether high NLR is associated with HT in this population.

METHODS

Data were prospectively collected for continuous patients with AIS treated with IVT and retrospectively analyzed. Clinical variables included age, sex, vascular risk factors, National Institutes of Health Stroke Scale (NIHSS) score, onset-to-treatment time, and initial hematologic and neuroimaging findings. HT was confirmed by imaging performed within 3 days after IVT. Symptomatic HT (sHT) was defined as NIHSS score increased by 4 points compared with that on admission according to previously published criteria. The NLR value was based on the blood examination before IVT, and high NLR was defined as ≥75th percentile.

RESULTS

The study included 285 patients (201 (70.5%) males, the mean age was 62.3 years (range 29-89)). Seventy-two (25.3%) patients presented with HT, including three (1.1%) with sHT. The median NLR was 2.700 (1.820-4.255, interquartile range). Seventy-one (24.9%) patients had a high NLR (≥4.255) on admission. Univariate analysis indicated that patients with HT had higher NIHSS scores (P < 0.001), systolic blood pressure (SBP), platelet counts, lymphocyte counts, and NLR (P < 0.001), systolic blood pressure (SBP), platelet counts, lymphocyte counts, and NLR (P < 0.001), systolic blood pressure (SBP), platelet counts, lymphocyte counts, and NLR (P < 0.001), systolic blood pressure (SBP), platelet counts, lymphocyte counts, and NLR (P < 0.001), systolic blood pressure (SBP), platelet counts, lymphocyte counts, and NLR (P < 0.001), systolic blood pressure (SBP), platelet counts, lymphocyte counts, and NLR (P < 0.001), systolic blood pressure (SBP), platelet counts, lymphocyte counts, and NLR (P < 0.001), systolic blood pressure (SBP), platelet counts, lymphocyte counts, and NLR (P < 0.001), systolic blood pressure (SBP), platelet counts, lymphocyte counts, and NLR (.

CONCLUSIONS

High NLR could be a useful marker for predicting HT in AIS patients after IVT.

Association between non-high-density lipoprotein cholesterol and haemorrhagic transformation in patients with acute ischaemic stroke

BACKGROUND

It is unclear whether non-high-density lipoprotein cholesterol (Non-HDL-C) is associated with haemorrhagic transformation (HT) after acute ischaemic stroke (AIS). We aimed to explore the association between Non-HDL-C and HT, as well as compare the predictive values of Non-HDL-C and low-density lipoprotein cholesterol (LDL-C) for HT.

METHODS

We consecutively enrolled AIS patients within 7 days of stroke onset. Participants were divided into four categories according to quartiles of Non-HDL-C. HT was assessed by follow-up brain imaging. We assessed the association between Non-HDL-C, LDL-C and HT in multivariate logistic regression analysis.

RESULTS

A total of 2043 patients were included, among whom 232 were identified as HT. Compared with the highest quartiles, the first, second and third quartiles of Non-HDL-C were associated with increased risk of HT (adjusted odds ratios [ORs] 1.74 [95% confidence interval [CI] 1.09-2.78], 2.01[95% CI 1.26-3.20], and 1.76 [95% CI 1.10-2.83], respectively, P for trend = 0.024). Similar results were found for LDL-C. There was significant interaction between Non-HDL-C and age (P for interaction = 0.021). The addition of Non-HDL-C and LDL-C to conventional factors significantly improved predictive values [Non-HDL-C, net reclassification index (NRI) 0.24, 95%CI 0.17-0.31, P < 0.001; LDL-C, NRI 0.15, 95%CI 0.08-0.22, P = 0.03].

CONCLUSIONS

Low Non-HDL-C was associated with increased risks of HT. In addition, Non-HDL-C has similar effects as LDL-C for predicting HT.

Effect of blood pressure parameters on functional independence in patients with acute ischemic stroke in the first 6 hours after endovascular thrombectomy

BACKGROUND AND PURPOSE

Studies have suggested that blood pressure (BP) levels after endovascular thrombectomy (EVT) are correlated with clinical outcomes. The aim of our study was to investigate the effect of BP in different time intervals within the first 24 hours after EVT on functional outcomes.

METHODS

Data of patients who received EVT for acute ischemic stroke at two institutions were reviewed. After EVT, hourly BP data were collected and divided into four time intervals: 1-6 hours, 7-12 hours, 13-18 hours, and 19-24 hours. The mean, maximum, and standard deviation (SD) of BP were calculated and compared with the outcome of interest in patients with successful recanalization. The outcome of interest was functional independence, which was defined as a 3-month modified Rankin Scale score of ≤2.

RESULTS

Of 224 patients with stroke who received EVT, 166 (74.1%) (mean age 70.2±13.1 years; 49.4% men) achieved successful recanalization and 82 (49.4%) exhibited functional independence. After adjustment for possible confounders, lower mean, maximum, and SD values of systolic and diastolic BP observed in the first 6 hours after EVT were independently associated with functional independence. Furthermore, the area under the receiver operating characteristic curve values observed for BP parameters for outcome prediction in the first 6 hours were the highest across the 24-hour period following EVT.

CONCLUSION

In patients with stroke who achieved successful recanalization, the first 6 hours after EVT was the key period influencing the correlation between BP and functional outcome.

Prognostic Significance of Pulse Pressure Variability During Mechanical Thrombectomy in Acute Ischemic Stroke Patients

Background Studies on the role of blood pressure ( BP ) variability specifically during mechanical thrombectomy ( MT ) are sparse and limited. Moreover, pulse pressure ( PP ) has not been considered as a potent hemodynamic parameter to describe BP variability during MT . We assessed the impact of PP variability on functional outcome in acute ischemic stroke patients with large vessel occlusion during MT . Methods and Results Acute ischemic stroke patients presenting with large vessel occlusion from January 2012 to June 2016 were included. BP data during MT were prospectively collected in the ETIS (Endovascular Treatment in Ischemic Stroke) registry. Logistic regression models were used to assess the association between PP coefficients of variation and functional outcome at 3 months (modified Rankin Scale). Among the 343 included patients, PP variability was significantly associated with worse 3-month modified Rankin Scale in univariable (odds ratio [OR] =1.56, 95% confidence interval [CI]: 1.24-1.96 per 1-unit increase, P=0.0002) and multivariable ordinal logistic regression (adjusted OR =1.40, 95% CI : 1.09-1.79, P=0.008). PP variability was also associated with unfavorable outcome (modified Rankin Scale 3-6) in univariable ( OR =1.53, 95% CI : 1.17-2.01, P=0.002) and multivariable analysis (adjusted OR =1.42, 95% CI : 1.02-1.98, P=0.04). There was an association between PP variability and 3-month all-cause mortality in univariable analysis ( OR = 1.37, 95% CI : 1.01-1.85 per 1-unit increase of the coefficient of variation of the PP , P=0.04), which did not remain significant after adjustment for potential confounders. Conclusions PP variability during MT is an independent predictor of worse clinical outcome in acute ischemic stroke patients. These findings support the need for a close monitoring of BP variability during MT . Whether pharmacological interventions aiming at reducing BP variability during MT could impact functional outcome needs to be determined.

Guidelines for the Early Management of Patients With Acute Ischemic Stroke: 2019 Update to the 2018 Guidelines for the Early Management of Acute Ischemic Stroke: A Guideline for Healthcare Professionals From the American Heart Association/American Stroke Association

Background and Purpose- The purpose of these guidelines is to provide an up-to-date comprehensive set of recommendations in a single document for clinicians caring for adult patients with acute arterial ischemic stroke. The intended audiences are prehospital care providers, physicians, allied health professionals, and hospital administrators. These guidelines supersede the 2013 Acute Ischemic Stroke (AIS) Guidelines and are an update of the 2018 AIS Guidelines. Methods- Members of the writing group were appointed by the American Heart Association (AHA) Stroke Council's Scientific Statements Oversight Committee, representing various areas of medical expertise. Members were not allowed to participate in discussions or to vote on topics relevant to their relations with industry. An update of the 2013 AIS Guidelines was originally published in January 2018. This guideline was approved by the AHA Science Advisory and Coordinating Committee and the AHA Executive Committee. In April 2018, a revision to these guidelines, deleting some recommendations, was published online by the AHA. The writing group was asked review the original document and revise if appropriate. In June 2018, the writing group submitted a document with minor changes and with inclusion of important newly published randomized controlled trials with >100 participants and clinical outcomes at least 90 days after AIS. The document was sent to 14 peer reviewers. The writing group evaluated the peer reviewers' comments and revised when appropriate. The current final document was approved by all members of the writing group except when relationships with industry precluded members from voting and by the governing bodies of the AHA. These guidelines use the American College of Cardiology/AHA 2015 Class of Recommendations and Level of Evidence and the new AHA guidelines format. Results- These guidelines detail prehospital care, urgent and emergency evaluation and treatment with intravenous and intra-arterial therapies, and in-hospital management, including secondary prevention measures that are appropriately instituted within the first 2 weeks. The guidelines support the overarching concept of stroke systems of care in both the prehospital and hospital settings. Conclusions- These guidelines provide general recommendations based on the currently available evidence to guide clinicians caring for adult patients with acute arterial ischemic stroke. In many instances, however, only limited data exist demonstrating the urgent need for continued research on treatment of acute ischemic stroke.

Association of maximal systolic blood pressure with poor outcome in patients with hyperattenuated lesions on immediate NCCT after mechanical thrombectomy

Background and purpose

This study aimed to investigate the relationship between blood pressure (BP) management and clinical outcome in patients with hyperattenuated lesions on non-contrast CT (NCCT) immediately after mechanical thrombectomy (MT).

Methods

We retrospectively reviewed our prospectively collected cohort for consecutive patients with acute ischemic stroke (AIS) who received MT between October 2013 and July 2018. Hourly systolic BP (SBP) and diastolic BP (DBP) values were recorded for 24 hours following MT, and then maximum SBP (SBPmax) and DBP (DBPmax) values were identified. Poor outcome was defined as 3-month modified Rankin score (mRS) 3–6 and parenchymal hemorrhage (PH) was defined according to the European Cooperative Acute Stroke Study (ECASS) II trial. Associations of BP parameters with poor outcome and PH were determined using binary logistic regression models. Receiver operating characteristics (ROC) curve analysis was used to determine the predictive value of BP.

Results

Initially 262 patients with AIS who received MT were reviewed and 148 patients with hyperattenuated lesions on immediate NCCT were enrolled in the final cohort for analysis. Binary logistic regression showed that every 10 mm Hg increase in SBPmax was independently associated with a poor outcome (OR 1.426; 95% CI 1.095 to 1.855; p=0.008) and PH (OR 1.025; 95% CI 1.005 to 1.480; p=0.044). SBP ≤140 mm Hg during the post-procedural 24-hour period was associated with lower odds of a poor outcome and PH compared with the other group.

Conclusions

Control of maximal SBP within 24 hours might be related to a low rate of PH and poor outcome in patients with hyperattenuated lesions on immediate NCCT after intervention.

Management of Blood Pressure After Acute Ischemic Stroke

PURPOSE OF REVIEW

The present manuscript examines the significance of blood pressure elevation in patients with acute ischemic stroke, the physiologic principles worthy of consideration during its treatment, and the recent empirical evidence that should guide management protocols. It also provides a sound and practical approach to treatment along the time continuum, with particular relevance to reperfusion strategies.

RECENT FINDINGS

The existing evidence shows that both insufficient and excessive blood pressures are detrimental to the outcome of patients with acute ischemic stroke. This "U-shaped" relation, however, relates to measurements at the time of presentation, and clinical studies lack detail and specificity relative to differential measurements along the time continuum, particularly prior to and following reperfusion. Extrapolating from recent series, it is possible to construct treatment protocols balanced for effectiveness and safety. The management of blood pressure after acute ischemic stroke is an important, complex, and challenging aspect of care, requiring a thorough understanding of cerebrovascular physiology. Along the time continuum, the therapeutic priorities start with the preservation of penumbral tissue prior to reperfusion and then follow with the limitation of the damaging effects of excessive blood pressure readings after reperfusion, optimizing the chances of improved outcomes.

Association of Elevated Blood Pressure Levels with Outcomes in Acute Ischemic Stroke Patients Treated with Intravenous Thrombolysis: A Systematic Review and Meta-Analysis

BACKGROUND AND PURPOSE

Although arbitrary blood pressure (BP) thresholds exist for acute ischemic stroke (AIS) patients eligible for intravenous thrombolysis (IVT), current international recommendations lack clarity on the impact of mean pre- and post-IVT BP levels on clinical outcomes.

METHODS

Eligible studies involving IVT-treated AIS patients were identified that reported the association of mean systolic BP (SBP) or diastolic BP levels before and after IVT with the following outcomes: 3-month favorable functional outcome (modified Rankin Scale [mRS] scores of 0-1) and 3-month functional independence (mRS scores of 0-2), 3-month mortality and symptomatic intracranial hemorrhage (sICH). Unadjusted analyses of standardized mean differences and adjusted analyses of studies reporting odds ratios (ORadj) per 10 mm Hg BP increment were performed using random-effects models.

RESULTS

We identified 26 studies comprising 56,513 patients. Higher pre- (P=0.02) and posttreatment (P=0.006) SBP levels were observed in patients with sICH. Patients with 3-month functional independence had lower post-treatment (P<0.001) SBP whereas trended towards lower pre-treatment (P=0.06) SBP. In adjusted analyses, elevated pre- (ORadj, 1.08; 95% confidence interval [CI], 1.01 to 1.16) and post-treatment (ORadj, 1.13; 95% CI, 1.01 to 1.25) SBP levels were associated with increased likelihood of sICH. Increasing pre- (ORadj, 0.91; 95% CI, 0.84 to 0.98) and post-treatment (ORadj, 0.70; 95% CI, 0.57 to 0.87) SBP values were also related to lower odds of 3-month functional independence.

CONCLUSION

s We found that elevated BP levels adversely impact AIS outcomes in patients receiving IVT. Future randomized-controlled clinical trials will provide definitive data on the aforementioned association.

Glomerular Filtration Rate is Associated with Hemorrhagic Transformation in Acute Ischemic Stroke Patients without Thrombolytic Therapy

Background:

Whether there is a relationship between glomerular filtration rate (GFR) and hemorrhagic transformation (HT) after acute ischemic stroke (AIS) is still under debate. The aim of our study was to determine whether the GFR level is a predictor of HT in AIS patients without thrombolytic therapy (TT).

Methods:

Consecutive AIS patients without TT were included in this prospective study from January 2014 to December 2016 in the First Affiliated Hospital of Chongqing Medical University. We divided them into two groups (HT and non-HT group) and meticulously collected baseline characteristics and laboratory and imaging data of interested individuals. Multivariate regression analysis was performed to assess the correlation between GFR and HT in stroke patients without TT.

Results:

Among 426 consecutive patients, 74 (17.3%) presented HT (mean age: 65 ± 12 years, number of male patients: 47) on the follow-up scans. In multivariate regression analysis, HT was significantly associated with low GFR (odds ratio [OR] = 3.708, confidence interval [CI] = 1.326–10.693, P = 0.013), atrial fibrillation (AF; OR = 2.444, CI = 1.087–5.356, P = 0.027), large cerebral infarction (OR = 2.583, CI = 1.236–5.262, P = 0.010), and hypoalbuminemia (HA; OR = 4.814, CI = 1.054–22.153, P = 0.037) for AIS patients without TT.

Conclusions:

The present study strongly showed that lower GFR is an independently predictor of HT; in addition, large infarct volume, AF, and HA are also important risks of HT for AIS patients without TT, which offered a practical information that risk factors should be paid attention or eliminated to prevent HT for stroke patients though the level of evidence seems to be unstable.

Dietary nitrate supplementation reduces low frequency blood pressure fluctuations in rats following distal middle cerebral artery occlusion

It is known that high blood pressure variability (BPV) in acute ischemic stroke is associated with adverse outcomes, yet there are no therapeutic treatments to reduce BPV. Studies have found increasing nitric oxide (NO) bioavailability improves neurological function following stroke, but whether dietary nitrate supplementation could reduce BPV remains unknown. We investigated the effects of dietary nitrate supplementation on heart rate (HR), blood pressure (BP), and beat-to-beat BPV using wireless telemetry in a rat model of distal middle cerebral artery occlusion. Blood pressure variability was characterized by spectral power analysis in the low frequency (LF; 0.2–0.6 Hz) range prestroke and during the 7 days poststroke in a control group ( n = 8) and a treatment group ( n = 8, 183 mg/l sodium nitrate in drinking water). Dietary nitrate supplementation moderately reduced systolic BPV in the LF range by ~11% compared with the control group ( P = 0.03), while resting BP and HR were not different between the two groups ( P = 0.28 and 0.33, respectively). Despite systolic BPV being reduced with dietary nitrate, we found no difference in infarct volumes between the treatment and the control groups (1.59 vs. 1.62 mm3, P = 0.86). These findings indicate that dietary nitrate supplementation is effective in reducing systolic BPV following stroke without affecting absolute BP. In light of mounting evidence linking increased BPV with poor stroke patient outcome, our data support the role of dietary nitrate as an adjunct treatment following ischemic stroke.

NEW & NOTEWORTHY Using a rat model of stroke, we found that dietary nitrate supplementation reduced low frequency blood pressure fluctuations following stroke without affecting absolute blood pressure values. Since blood pressure fluctuations are associated with poor clinical outcome in stroke patients, our findings indicate that dietary nitrate could be an effective strategy for reducing blood pressure fluctuations, which could help reduce stroke severity and improve patient recovery.

Increased arterial stiffness is an independent risk factor for hemorrhagic transformation in ischemic stroke undergoing thrombolysis

BACKGROUND

Hemorrhagic transformation (HT) is a multifactorial phenomenon and represents a possible complication of ischemic stroke, especially after thrombolytic treatment. Increased arterial stiffness has been associated with intracranial hemorrhage, but there is no evidence of association with HT after thrombolytic therapy. The aim of our study is to investigate a possible link between arterial stiffness and HT occurrence after thrombolytic therapy in patients with ischemic stroke.

METHODS

We enrolled 258 patients (135 males, 123 females; mean age: 73±12years) with acute ischemic stroke undergoing intravenous thrombolysis or/and mechanical thrombectomy. All stroke patients underwent neuroimaging examination, 24-h heart rate and blood pressure monitoring and brain CT-scan after 24-72h to evaluate HT occurrence. The linear regression slope of diastolic on systolic blood pressure was obtained and assumed as a global measure of arterial compliance, and its complement (1 minus the slope), named arterial stiffness index (ASI), has been taken as a measure of arterial stiffness.

RESULTS

Out of 258, HT occurred in 55 patients. ASI was significantly higher in patients with HT than in patients without HT (0.70±0.12 vs 0.62±0.14, p<0.001). Logistic regression model showed ASI as independent predictors of HT (OR: 1.9, 95% CI: 1.09-3.02, for every 0.2 increase of ASI): in particular, OR was 5.2 (CI: 2.22-12.24) when ASI was >0.71, in comparison with ASI lower than 0.57.

CONCLUSIONS

Our results point to arterial stiffness as a novel independent risk factor for HT after ischemic stroke treated with thrombolysis, suggesting a particularly high bleeding risk when ASI is >0.71.

2018 Guidelines for the Early Management of Patients With Acute Ischemic Stroke: A Guideline for Healthcare Professionals From the American Heart Association/American Stroke Association

BACKGROUND AND PURPOSE

The purpose of these guidelines is to provide an up-to-date comprehensive set of recommendations for clinicians caring for adult patients with acute arterial ischemic stroke in a single document. The intended audiences are prehospital care providers, physicians, allied health professionals, and hospital administrators. These guidelines supersede the 2013 guidelines and subsequent updates.

METHODS

Members of the writing group were appointed by the American Heart Association Stroke Council's Scientific Statements Oversight Committee, representing various areas of medical expertise. Strict adherence to the American Heart Association conflict of interest policy was maintained. Members were not allowed to participate in discussions or to vote on topics relevant to their relations with industry. The members of the writing group unanimously approved all recommendations except when relations with industry precluded members voting. Prerelease review of the draft guideline was performed by 4 expert peer reviewers and by the members of the Stroke Council's Scientific Statements Oversight Committee and Stroke Council Leadership Committee. These guidelines use the American College of Cardiology/American Heart Association 2015 Class of Recommendations and Levels of Evidence and the new American Heart Association guidelines format.

RESULTS

These guidelines detail prehospital care, urgent and emergency evaluation and treatment with intravenous and intra-arterial therapies, and in-hospital management, including secondary prevention measures that are appropriately instituted within the first 2 weeks. The guidelines support the overarching concept of stroke systems of care in both the prehospital and hospital settings.

CONCLUSIONS

These guidelines are based on the best evidence currently available. In many instances, however, only limited data exist demonstrating the urgent need for continued research on treatment of acute ischemic stroke.

Continuous-Infusion Labetalol vs Nicardipine for Hypertension Management in Stroke Patients

BACKGROUND

Labetalol and nicardipine are antihypertensives commonly used in the management of elevated blood pressure (BP) following an acute stroke, but there is limited evidence to suggest which agent as a continuous infusion should be used preferentially in this setting.

OBJECTIVE

This study aimed to compare the safety, efficacy, and ease of administration of continuous-infusion labetalol with continuous-infusion nicardipine following an acute stroke.

METHODS

This retrospective cohort study of patients with acute ischemic stroke or intracerebral hemorrhage included patients if they received either study agent within 24 hours of admission. The primary outcome was percent time spent at goal BP. Secondary outcomes included time to goal BP, the number of dose adjustments, and use of rescue antihypertensives.

RESULTS

The analysis included 99 patients who received labetalol- (n = 34) or nicardipine- (n = 65) continuous infusions. Intracerebral hemorrhage was the most common stroke subset (n = 81) followed by acute ischemic stroke (n = 18). There was no statistical difference in time at goal BP (labetalol 68.0%, nicardipine 67.0%; P = .885), rescue antihypertensive use (labetalol 14.7%, nicardipine 24.6%; P = .2570), time spent 10% above or below mean systolic BP (labetalol 35.5%, nicardipine 33.5%; P = .885), time to goal BP (labetalol 81.4 minutes, nicardipine 56.3 minutes; P = .162), and mean number of dose adjustments (labetalol 5.9, nicardipine 6.9; P = .262).

CONCLUSIONS

Labetalol- and nicardipine-continuous infusions were comparable in the studied safety and efficacy outcomes including time at goal and BP variability. Further prospective studies are needed to validate these safety and efficacy findings and to assess clinical outcomes.

Midterm Blood Pressure Variability Is Associated with Poststroke Cognitive Impairment: A Prospective Cohort Study

Objective

The aim of this study was to investigate the relationship between blood pressure variability (BPV) and poststroke cognitive impairment (PSCI).

Methods

Seven-hundred ninety-six patients with acute ischemic stroke were included in this study. Midterm BPV was evaluated by calculating the SD and coefficient of variation (CV, 100 × SD/mean) of systolic blood pressure (SBP) and diastolic blood pressure during the 7 days after stroke onset. Cognitive function was assessed using the Montreal Cognitive Assessment (MoCA) at admission and at all follow-up visits. Patients with MoCA scores <26 were considered to have PSCI.

Results

The incidence of PSCI reached its peak (72%) 3 months after stroke onset and decreased to 30.3% at 12 months poststroke. After adjusting for covariables, the increase in the prevalence of PSCI at 3 months was independently associated with increases in the CV of blood pressure during the 7 days after stroke [odds ratios and 95% CI for patients in the second to fifth quintiles of SBP CV were 2.28 (1.18, 4.39), 2.33 (1.18, 4.62), 2.69 (1.31, 5.53), and 4.76 (1.95, 11.67), respectively]. Sub-analysis of the MoCA scores revealed that the patients had impairments in visuoperceptual abilities and executive functions, as well as in naming and delayed recall (p < 0.05).

Conclusion

Midterm BPV during the early phase of acute ischemic stroke is independently associated with PSCI, especially in the visuoperceptual, executive, and delayed recall domains.

Clinical Trial Registration

http://www.chictr.org.cn, identifier ChiCTR-TRC-14004804.

Anesthesia for Endovascular Approaches to Acute Ischemic Stroke

Involvement of the Anesthesiologist in the early stages of care for acute ischemic stroke patient undergoing endovascular treatment is essential. Anesthetic management includes the anesthetic technique (general anesthesia vs sedation), a matter of much debate and an area in need of well-designed prospective studies. The large numbers of confounding factors make the design of such studies a difficult process. A universally agreed point in the endovascular management of acute ischemic stroke is the importance of decreasing the time to revascularization. Hemodynamic and ventilatory management and implementation of neuroprotective modalities and treatment of acute procedural complications are important components of the anesthetic plan.