The Relationship between Blood Pressure Variability, Recanalization Degree, and Clinical Outcome in Large Vessel Occlusive Stroke after an Intra-Arterial Thrombectomy

Safety and Efficacy of Intensive Blood Pressure-Lowering After Successful Endovascular Therapy in AIS: A Meta-Analysis

OBJECTIVES

Higher blood pressure has been proven to be associated with poorer functional outcomes after successful reperfusion by EVT. However, the effect of intensive blood pressure-lowering regimens in these patients remains controversial and ambiguous in clinical practice. We propose further analysis aimed at determining the effect of an intensive blood pressure-lowering regimen after EVT in AIS.

METHODS

The protocol registered in PROSPERO CRD42023360989. We performed a systematic search that was comprehensively executed in online databases for studies published up to June 2022. Eligibility criteria were established based on the PICOS model. The Cochrane risk of bias algorithm was used to evaluate the risk of bias. The effect models were applied to calculate the pooled ORs and CIs via Review Manager 5.4 software.

RESULTS

A total of 1582 citations were identified, 3 randomized clinical trials and 2 retrospective cohort studies were included. Data from 3211 patients were analyzed. We revealed that intensive blood pressure-lowering interventions could significantly reduce symptomatic intraparenchymal hemorrhage compared with standard blood pressure lowering. Nevertheless, favorable functional outcome, poor outcome, all-cause mortality within 3 months and intraparenchymal hemorrhage in 24 hours showed no significant differences. Subgroup analysis revealed the variability of systolic blood pressure within 24 hours after EVT was not associated with odds of poor outcome and intraparenchymal hemorrhage.

CONCLUSIONS

Based on the current evidence, intensive blood pressure-lowering regimen was superior to standard blood pressure-lowering regimen for a reduced risk of symptomatic intraparenchymal hemorrhage in AIS patients treated with EVT, but there was no statistically significant difference found between the 2 regimens for the other 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.

Association between blood pressure variability and outcomes after endovascular thrombectomy for acute ischemic stroke: An individual patient data meta-analysis

INTRODUCTION

Data on the association between blood pressure variability (BPV) after endovascular thrombectomy (EVT) for acute ischemic stroke (AIS) and outcomes are limited. We sought to identify whether BPV within the first 24 hours post EVT was associated with key stroke outcomes.

METHODS

We combined individual patient-data from five studies among AIS-patients who underwent EVT, that provided individual BP measurements after the end of the procedure. BPV was estimated as either systolic-BP (SBP) standard deviation (SD) or coefficient of variation (CV) over 24 h post-EVT. We used a logistic mixed-effects model to estimate the association [expressed as adjusted odds ratios (aOR)] between tertiles of BPV and outcomes of 90-day mortality, 90-day death or disability [modified Rankin Scale-score (mRS) > 2], 90-day functional impairment (⩾1-point increase across all mRS-scores), and symptomatic intracranial hemorrhage (sICH), adjusting for age, sex, stroke severity, co-morbidities, pretreatment with intravenous thrombolysis, successful recanalization, and mean SBP and diastolic-BP levels within the first 24 hours post EVT.

RESULTS

There were 2640 AIS-patients included in the analysis. The highest tertile of SBP-SD was associated with higher 90-day mortality (aOR:1.44;95% CI:1.08-1.92), 90-day death or disability (aOR:1.49;95% CI:1.18-1.89), and 90-day functional impairment (adjusted common OR:1.42;95% CI:1.18-1.72), but not with sICH (aOR:1.22;95% CI:0.76-1.98). Similarly, the highest tertile of SBP-CV was associated with higher 90-day mortality (aOR:1.33;95% CI:1.01-1.74), 90-day death or disability (aOR:1.50;95% CI:1.19-1.89), and 90-day functional impairment (adjusted common OR:1.38;95% CI:1.15-1.65), but not with sICH (aOR:1.33;95% CI:0.83-2.14).

CONCLUSIONS

BPV after EVT appears to be associated with higher mortality and disability, independently of mean BP levels within the first 24 h post EVT. BPV in the first 24 h may be a novel target to improve outcomes after EVT for AIS.

Prediction of blood pressure variability during thrombectomy using supervised machine learning and outcomes of patients with ischemic stroke from large vessel occlusion

Mechanical thrombectomy (MT) is the standard of care for patients with acute ischemic stroke from large vessel occlusion (AIS-LVO). The association of blood pressure variability (BPV) during MT and outcomes are unknown. We leveraged a supervised machine learning algorithm to predict patient characteristics that are associated with BPV indices. We performed a retrospective review of our comprehensive stroke center's registry of all adult patients undergoing MT between 01/01/2016 and 12/31/2019. The primary outcome was poor functional independence, defined as 90-day modified Rankin Scale (mRS) ≥ 3. We used probit analysis and multivariate logistic regressions to evaluate the association of patients' clinical factors and outcomes. We applied a machine learning algorithm (random forest, RF) to determine predictive factors for the different BPV indices during MT. Evaluation was performed with root-mean-square error (RMSE) and normalized-RMSE (nRMSE) metrics. We analyzed 375 patients with mean age (± standard deviation [SD]) of 65 (15) years. There were 234 (62%) patients with mRS ≥ 3. Univariate probit analysis demonstrated that BPV during MT was associated with poor functional independence. Multivariable logistic regression showed that age, admission National Institutes of Health Stroke Scale (NIHSS), mechanical ventilation, and thrombolysis in cerebral infarction (TICI) score (OR 0.42, 95% CI 0.17-0.98, P = 0.044) were significantly associated with outcome. RF analysis identified that the interval from last-known-well time-to-groin puncture, age, and mechanical ventilation were among important factors significantly associated with BPV. BPV during MT was associated with functional outcome in univariate probit analysis but not in multivariable regression analysis, however, NIHSS and TICI score were. RF algorithm identified risk factors influencing patients' BPV during MT. While awaiting further studies' results, clinicians should still monitor and avoid high BPV during thrombectomy while triaging AIS-LVO candidates quickly to MT.

Impact of leukoaraiosis or blood pressure on clinical outcome, mortality and symptomatic intracerebral hemorrhage after mechanical thrombectomy in acute ischemic stroke

We aimed to study the impact of leukoaraiosis (LA) and blood pressure (BP) on clinical outcome, mortality and symptomatic intracerebral hemorrhage (sICH) in acute ischemic stroke (AIS) patients treated with mechanical thrombectomy (MT). We analyzed data retrospectively from 521 patients with anterior large vessel occlusion treated with MT. LA was dichotomized in 0-2 (absent-to-moderate) versus 3-4 (moderate-to-severe) according to the van Swieten scale. Various systolic (SBP) and diastolic (DBP) BP parameters during the first 24 h were collected. Multivariable logistic regressions were performed to identify predictors of a poor 90-day outcome, mortality and sICH. LA was significantly associated with poor outcome (OR 3.2; p < 0.001) and mortality (OR 3.19; p = 0.008), but not sICH (p = 0.19). Higher maximum SBP was significantly associated with poor outcome (OR per 10 mmHg increase = 1.21; p = 0.009) and lower mean DBP was a predictor of mortality (OR per 10 mmHg increase = 0.53; p < 0.001). In the univariate analysis high SBP variability was associated with poor outcome, mortality and sICH, but not in the multivariate model. There was no association between BP and sICH. Severity of LA, SBP variability, high maximum SBP and low DBP are associated with either poor outcome or mortality in AIS patients undergoing MT. However, neither LA nor BP were associated with sICH in our cohort. Thus, mechanisms of the negative impact on outcome remain unclear. Further studies on impact of BP course and its mechanisms and interventions are needed to improve outcome in patients undergoing MT.

Temporal profiles of systolic blood pressure variability and neurologic outcomes after endovascular thrombectomy

Introduction

Observational studies have found an increased risk of hemorrhagic transformation and worse functional outcomes in patients with higher systolic blood pressure variability (BPV). However, the time-varying behavior of BPV after endovascular thrombectomy (EVT) and its effects on functional outcome have not been well characterized.

Patients and methods

We analyzed data from an international cohort of patients with large-vessel occlusion stroke who underwent EVT at 11 centers across North America, Europe, and Asia. Repeated time-stamped blood pressure data were recorded for the first 72 h after thrombectomy. Parameters of BPV were calculated in 12-h epochs using five established methodologies. Systolic BPV trajectories were generated using group-based trajectory modeling, which separates heterogeneous longitudinal data into groups with similar patterns.

Results

Of the 2041 patients (age 69 ± 14, 51.4% male, NIHSS 15 ± 7, mean number of BP measurements 50 ± 28) included in our analysis, 1293 (63.4%) had a poor 90-day outcome (mRS ⩾ 3) or a poor discharge outcome (mRS ⩾ 3). We identified three distinct SBP trajectories: low (25%), moderate (64%), and high (11%). Compared to patients with low BPV, those in the highest trajectory group had a significantly greater risk of a poor functional outcome after adjusting for relevant confounders (OR 2.2; 95% CI 1.2-3.9; p = 0.008). In addition, patients with poor outcomes had significantly higher systolic BPV during the epochs that define the first 24 h after EVT (p < 0.001).

Discussion and conclusions

Acute ischemic stroke patients demonstrate three unique systolic BPV trajectories that differ in their association with functional outcome. Further research is needed to rapidly identify individuals with high-risk BPV trajectories and to develop treatment strategies for targeting high BPV.

Effect of blood pressure on the prognosis of acute ischemic stroke patients caused by anterior circulation large vessel occlusion without recanalization

PURPOSE

To explore the effect of blood pressure on the prognosis of acute ischemic stroke patients caused by anterior circulation large vessel occlusion without recanalization.

METHODS

Acute ischemic stroke patients caused by anterior circulation large vessel occlusion without recanalization were retrospectively collected. All patients were divided into the functional independent group and non-functional independent group, death group and non-death group based on the 90-day mRS score. Logistic regression was applied to analyze the relationship between the highest systolic blood pressure, the average systolic blood pressure, the lowest systolic blood pressure, the highest diastolic blood pressure, the average diastolic blood pressure, the lowest diastolic blood pressure in the first 24 h after admission and the functional prognosis as well as the complications after 90 days. The independent impact factors selected from regression analysis were used to investigate the blood pressure with prognostic value by receiver operating characteristic curve (ROC).

RESULTS

A total of 70 patients were recruited in this study. Among them, 39 cases (55.71%) were male and 31 cases (44.29%) were female, with a mean age of 61.83 ± 15.24 years old. 15 cases (21.43%) had a favorable 90-day outcome, and the other 55 cases (78.57%) had a higher mRS Score. After a 90-day follow-up, univariate analysis showed that hypertension and hyperlipidemia, highest systolic blood pressure, mean systolic blood pressure and NIHSS score were statistically significant in two groups with or without functional independence, while the NIHSS score at admission, systolic blood pressure at admission, average systolic blood pressure, highest systolic blood pressure and diastolic blood pressure were statistically significant in patients with death outcomes (P < 0.05). Multivariate regression analysis suggested that the highest systolic blood pressure was statistically significant (P < 0.05), the further ROC curve results showed the cut-off value of the highest systolic blood pressure was 180.5 mmHg, with a sensitivity of 82.35% and a specificity of 81.13%. The highest Youden's index was 0.6348.

CONCLUSION

For acute ischemic stroke patients caused by anterior circulation large vessel occlusion without recanalization, the appropriate reduction of blood pressure within 24 h after admission may have a positive effect on the clinical prognosis. The 90-day mortality of acute ischemic stroke patients without revascularization was independently related to the highest systolic blood pressure. The risk of death was increased when the highest systolic blood pressure was greater than 180.5 mmHg.

Association between systolic blood pressure parameters and unexplained early neurological deterioration (UnND) in acute ischemic stroke patients treated with mechanical thrombectomy

Background:

Neurological deterioration (ND) after mechanical thrombectomy (MT) of acute ischemic stroke (AIS) in anterior circulation is an important complication associated with a poor outcome. Moreover, evident causes of ND may remain unexplained (UnND).

Objective:

We sought to evaluate the association of the systolic blood pressure (SBP) parameters before MT, during MT, and during a 24-h period after MT with UnND.

Methods:

We analyzed 382 MT-treated AIS patients in two stroke centers from 2017 to 2019. The patients with unsuccessful recanalization and/or with symptomatic intracerebral hemorrhage after MT were excluded. Multivariate logistic regression analysis was used to identify the SBP parameters that predict UnND.

Results:

There were 5.9% patients with UnND within 24 h after MT among patients with successful recanalization what comprises 4.9% of all patients who had undergone MT. SBP > 180 mmHg on admission (odds ratio (OR): 4, 95% confidence interval (CI): 1.6–10, p = 0.004) and a drop of SBP below100 mmHg during MT (OR: 4.7, 95% CI: 1.3–17, p = 0.019) were associated with UnND occurrence within 7 days without a significant association with UnND within 24 h. UnND within 7 days was predicted by the episodes of SBP exceeding the level of SBP observed before the groin puncture and occurring over the first 2 h following recanalization (OR: 5, 95% CI: 1.3–19, p = 0.021), an increase of SBP of more than 20% within 2–24 h after MT (OR: 3.4, 95% CI: 1.1–10, p = 0.035), and a drop of SBP below 100 mmHg after MT (OR: 3.2, 95% CI: 1.1–9, p = 0.039).

Conclusion:

The association between the SBP parameters and UnND depends on the treatment period and the time of UnND occurrence. The J/U resembling relationship between SBP and UnEND was established during a 24-h period after MT.

Endovascular Treatment Combined With Standard Medical Treatment Improves Outcomes of Posterior Circulation Stroke: A Systematic Review and Meta-Analysis

Aims

Whether endovascular treatment (EVT) can further improve the prognosis of patients with posterior circulation ischemic stroke (PCIS) is unclear. This meta-analysis aims to compare the efficacy and safety of PCIS patients treated with EVT plus standard medical treatment (SMT) and SMT alone.

Methods

We systematically searched for relevant randomized controlled trials (RCTs) and prospective cohort trials in MEDLINE, EMBASE, and the Cochrane Library up to February 2022. The primary outcome was favorable functional outcome of the modified Rankin Scale (mRS) with scores of 0-2 or 0-3; secondary outcomes included successful recanalization rate, intracranial hemorrhage (ICH), or symptomatic intracranial hemorrhage (sICH) after treatment and 90-day mortality.

Results

We identified six studies including 1, 385 PCIS patients (957 with EVT plus SMT; 428 with SMT alone). EVT plus SMT substantially improved 90-day functional outcomes compared with SMT alone [mRS score of 0-2: RR=1.95, 95% CI (1.52 - 2.51), P < 0.001; mRS score of 0-3: RR = 1.85, 95% CI (1.49 - 2.30), P < 0.001, respectively]. Moreover, compared with SMT, combined treatment significantly improved the rate of successful recanalization [RR = 5.03, 95% CI (3.96-6.40), P < 0.001] and reduced 90-day mortality [RR = 0.71, 95% CI (0.63-0.79), P < 0.001] despite a higher risk of ICH [RR = 6.13, 95% CI (2.50-15.02), P < 0.001] and sICH [RR = 10.47, 95% CI [2.79-39.32), P = 0.001].

Conclusion

Low-to-moderate evidence from RCTs and non-RCTs showed that increased ICH and sICH risk of EVT plus SMT did not translate to a higher risk of unfavorable outcomes compared with SMT and could even promote independence at 90 days in a real-world cohort.

Blood Pressure After Endovascular Thrombectomy and Outcomes in Patients With Acute Ischemic Stroke: An Individual Patient Data Meta-analysis

OBJECTIVE

To explore the association between blood pressure (BP) levels after endovascular thrombectomy (EVT) and the clinical outcomes of acute ischemic stroke (AIS) patients with large vessel occlusion (LVO).

METHODS

A study was eligible if it enrolled AIS patients older than 18 years, with an LVO treated with either successful or unsuccessful EVT, and provided either individual or mean 24-hour systolic BP values after the end of the EVT procedure. Individual patient data from all studies were analyzed using a generalized linear mixed-effects model.

RESULTS

A total of 5874 patients (mean age: 69±14 years, 50% women, median NIHSS on admission: 16) from 7 published studies were included. Increasing mean systolic BP levels per 10 mm Hg during the first 24 hours after the end of the EVT were associated with a lower odds of functional improvement (unadjusted common OR=0.82, 95%CI:0.80-0.85; adjusted common OR=0.88, 95%CI:0.84-0.93) and modified Ranking Scale score≤2 (unadjusted OR=0.82, 95%CI:0.79-0.85; adjusted OR=0.87, 95%CI:0.82-0.93), and a higher odds of all-cause mortality (unadjusted OR=1.18, 95%CI:1.13-1.24; adjusted OR=1.15, 95%CI:1.06-1.23) at 3 months. Higher 24-hour mean systolic BP levels were also associated with an increased likelihood of early neurological deterioration (unadjusted OR=1.14, 95%CI:1.07-1.21; adjusted OR=1.14, 95%CI:1.03-1.24) and a higher odds of symptomatic intracranial hemorrhage (unadjusted OR=1.20, 95%CI:1.09-1.29; adjusted OR=1.20, 95%CI:1.03-1.38) after EVT.

CONCLUSION

Increased mean systolic BP levels in the first 24 hours after EVT are independently associated with a higher odds of symptomatic intracranial hemorrhage, early neurological deterioration, three-month mortality, and worse three-month functional outcomes.

Systolic blood pressure variability following endovascular thrombectomy and clinical outcome in acute ischemic stroke: A meta-analysis

Blood pressure variability (BPV) has been linked with the outcome of acute ischemic stroke (AIS) after endovascular thrombectomy (EVT). However, the association of the stroke outcome with specific short-term BPV parameters is unclear. We did a systematic literature search for studies published from January 2010 to September 2020. Eligibility criteria included studies with (1) AIS patients treated with EVT with or without thrombolysis; and (2) analysis of the association between short-term systolic BPV parameter and clinical outcomes. Systolic BPV parameters included standard deviation (SD), coefficient of Variation (CoV), successive Variation (SV), and Variation independent of mean. A total of 11 studies were meta-analyzed, comprising 3520 patients who underwent EVT. Lower odds of achieving good functional outcome at 3 months; that is, modified Rankin Scale (mRS) score ≤2 was associated with SD (OR, 0.854; p = .02), CoV (OR, 0.572; p = .04), SV (OR 0.41; p = .00) of systolic blood pressure (SBP). Likewise, higher odds of one-point increase in mRS score was associated with SD (OR 1.42; p = .03), CoV (OR 1.464; p = .00) and SV (OR 2.605; p = .00) of SBP. However, high BPV was not associated with symptomatic intracranial hemorrhage and all-cause mortality at 90 days. The association of BPV and early neurological deterioration was inconclusive. Based on the available studies, short-term systolic BPV is indicative of the clinical outcome of patients following EVT in AIS. Further research should focus on personalized blood pressure management strategies, rather than a one-size-fits-all approach.

Blood Pressure Management After Endovascular Thrombectomy

Endovascular thrombectomy (EVT) has changed the landscape of acute stroke therapy and has become the standard of care for selected patients presenting with anterior circulation large-vessel occlusion (LVO) stroke. Despite successful reperfusion, many patients with LVO stroke do not regain functional independence. Particularly, patients presenting with extremes of blood pressure (BP) or hemodynamic variability are found to have a worse clinical recovery, suggesting blood pressure optimization as a potential neuroprotective strategy. Current guidelines acknowledge the lack of randomized trials to evaluate the optimal hemodynamic management during the immediate post-stroke period. Following reperfusion, lower blood pressure targets may be warranted to prevent reperfusion injury and promote penumbral recovery, but adequate BP targets adjusted to individual patient factors such as degree of reperfusion, infarct size, and overall hemodynamic status remain undefined. This narrative review outlines the physiological mechanisms of BP control after EVT and summarizes key observational studies and clinical trials evaluating post-EVT BP targets. It also discusses novel treatment strategies and areas of future research that could aid in the determination of the optimal post-EVT blood pressure.

Hemodynamics of Leptomeningeal Collaterals after Large Vessel Occlusion and Blood Pressure Management with Endovascular Treatment

Endovascular therapy (EVT) is an effective treatment for ischemic stroke due to large vessel occlusion (LVO). Unlike intravenous thrombolysis, EVT enables visualization of the restoration of blood flow, also known as successful reperfusion in real time. However, until successful reperfusion is achieved, the survival of the ischemic brain is mainly dependent on blood flow from the leptomeningeal collaterals (LMC). It plays a critical role in maintaining tissue perfusion after LVO via pre-existing channels between the arborizing pial small arteries or arterioles overlying the cerebral hemispheres. In the ischemic territory where the physiologic cerebral autoregulation is impaired and the pial arteries are maximally dilated within their capacity, the direction and amount of LMC perfusion rely on the systemic perfusion, which can be estimated by measuring blood pressure (BP). After the EVT procedure, treatment focuses on mitigating the risk of hemorrhagic transformation, potentially via BP reduction. Thus, BP management may be a key component of acute care for patients with LVO stroke. However, the guidelines on BP management during and after EVT are limited, mostly due to the scarcity of high-level evidence on this issue. In this review, we aim to summarize the anatomical and physiological characteristics of LMC to maintain cerebral perfusion after acute LVO, along with a landscape summary of the literature on BP management in endovascular treatment. The objective of this review is to describe the mechanistic association between systemic BP and collateral perfusion after LVO and thus provide clinical and research perspectives on this topic.

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.

Adverse Outcomes Associated With Higher Mean Blood Pressure and Greater Blood Pressure Variability Immediately After Successful Embolectomy in Those With Acute Ischemic Stroke, and the Influence of Pretreatment Collateral Circulation Status

Background

To investigate whether collateral status could modify the associations between post‐thrombectomy blood pressure (BP) measures and outcomes.

Methods and Results

Patients with anterior‐circulation large‐vessel‐occlusion successfully recanalized in a multicenter endovascular thrombectomy registry were enrolled. Pretreatment collateral status was graded and dichotomized (good/poor) in angiography. Maximum, minimum, and mean systolic BP (SBP) and BP variability (assessed by the SD, coefficient of variation) during the initial 24 hours after endovascular thrombectomy were obtained. The primary outcome was unfavorable 90‐day outcome (modified Rankin Scale score 3–6). Secondary outcomes included symptomatic intracranial hemorrhage and 90‐day mortality. Adjusted odds ratios (aOR) of BP parameters over the outcomes were obtained in all patients and in patients with good/poor collaterals. Among 596 patients (mean age 66 years; 59.9% males), 302 (50.7%) patients had unfavorable 90‐day outcome. In multivariable analyses, higher mean SBP (aOR, 1.59 per 10 mm Hg increment; 95% CI, 1.26–2.02; P<0.001), mean SBP >140 mm Hg (versus ≤120 mm Hg; aOR, 4.27; 95% CI, 1.66–10.97; P=0.002), and higher SBP SD (aOR, 1.08 per 1‐SD increment; 95% CI, 1.01–1.16; P=0.02) were respectively associated with unfavorable 90‐day outcome in patients with poor collateral but not in those with good collateral. A marginal interaction between SBP coefficient of variation tertiles and collaterals on 90‐day functional outcome (P for interaction, 0.09) was observed. A significant interaction between SBP coefficient of variation tertiles and collaterals on 90‐day mortality (P for interaction, 0.03) was observed.

Conclusions

Higher postprocedural BP is associated with 90‐day unfavorable outcomes after successful endovascular thrombectomy in patients with poor collateral.

Registration

URL: https://www.chictr.org.cn; Unique identifier: ChiCTR1900022154.

Spontaneous systolic blood pressure drop early after mechanical thrombectomy predicts dramatic neurological recovery in ischaemic stroke patients

Introduction

Spontaneous blood pressure drop within the first 24 h has been reported following arterial recanalisation in ischaemic stroke patients. We aimed to assess if spontaneous blood pressure drop within the first hour after mechanical thrombectomy is a marker of early neurological recovery.

Patients and methods

Retrospective observational single-centre study including ischaemic stroke patients treated with mechanical thrombectomy. Blood pressure parameters from admission, mechanical thrombectomy start, mechanical thrombectomy end and hourly within 24 h after mechanical thrombectomy were reviewed. Primary outcome was early dramatic neurological recovery (8-point-reduction in NIHSS or NIHSS ≤ 2 at 24 h). Secondary outcome was functional independence at 90 days (mRankin 0-2).

Results

We included 458 patients in our analysis. Two-hundred (43.7%) patients achieved dramatic neurological recovery following mechanical thrombectomy. One hour after mechanical thrombectomy end, median systolic blood pressure was significantly different between outcome groups (129 vs. 138 mmHg, p = 0.005) and a higher drop in median systolic blood pressure was seen in the dramatic neurological recovery group (15 vs. 9 mmHg). Optimal cut-off for predicting dramatic neurological recovery was a systolic blood pressure drop of 10.5 mmHg (sensitivity 0.54, specificity 0.55, AUC 0.55). On multivariate analysis, spontaneous systolic blood pressure drop was associated with higher odds of achieving dramatic neurological recovery (OR for 10 mmHg blood pressure drop 1.14, 95% CI 1.01-1.29, p = 0.04). No significative association between any blood pressure parameter drop and functional independence at 90 days was found.

Discussion

We hypothesised that spontaneous systolic blood pressure drop is a marker of successful reperfusion and, therefore, a marker of improvement of cerebral autoregulation due to the reduced final ischaemic core.

Conclusion

Spontaneous systolic blood pressure drop after mechanical thrombectomy is an early predictor of dramatic neurological recovery.

Impact of Sleep Deprivation in the Neurological Intensive Care Unit: A Narrative Review

Sleep is fundamental for everyday functioning, yet it is often negatively impacted in critically ill patients by the intensive care setting. With a focus on the neurological intensive care unit (NeuroICU), this narrative review summarizes methods of measuring sleep and addresses common causes of sleep disturbance in the hospital including environmental, pharmacological, and patient-related factors. The effects of sleep deprivation on the cardiovascular, pulmonary, immune, endocrine, and neuropsychological systems are discussed, with a focus on short-term deprivation in critically ill populations. Where evidence is lacking in the literature, long-term sleep deprivation studies and the effects of sleep deprivation in healthy individuals are also referenced. Lastly, strategies for the promotion of sleep in the NeuroICU are presented.

Blood Pressure Management Before, During, and After Endovascular Thrombectomy for Acute Ischemic Stroke

There is an absence of specific evidence or guideline recommendations on blood pressure management for large vessel occlusion stroke patients. Until randomized data are available, the periprocedural blood pressure management of patients undergoing endovascular thrombectomy can be viewed in two phases relative to the achievement of recanalization. In the hyperacute phase, prior to recanalization, hypotension should be avoided to maintain adequate penumbral perfusion. The American Heart Association guidelines should be followed for the upper end of prethrombectomy blood pressure: ≤185/110 mm Hg, unless post-tissue plasminogen activator administration when the goal is <180/105 mm Hg. After successful recanalization (thrombolysis in cerebral infarction [TICI]: 2b-3), we recommend a target of a maximum systolic blood pressure of < 160 mm Hg, while the persistently occluded patients (TICI < 2b) may require more permissive goals up to <180/105 mm Hg. Future research should focus on generating randomized data on optimal blood pressure management both before and after endovascular thrombectomy, to optimize patient outcomes for these divergent clinical scenarios.

Association Between Blood Pressure Variability and Short-Term Outcome After Intra-arterial Thrombectomy in Acute Stroke Patients With Large-Vessel Occlusion

The optimal range of blood pressure variability (BPV) for acute stroke patients with large-vessel occlusion (LVO) remains unclear. This study investigated the association between BPV from admission through the first 24 h after intra-arterial thrombectomy (IAT) and short-term outcome in LVO patients. We retrospectively analyzed 257 consecutive patients with LVO stroke who were treated with IAT. BP values were recorded at 2-h intervals from admission through the first 24 h after IAT. BPV, as reflected by pulse pressure variability (PPV), was determined based on standard deviation (SD), coefficient of variation (CV), successive variation (SV), and the difference between maximum and minimum blood pressure (ΔBP; systolic BP minus diastolic BP). The association between BPV and clinical outcome (Modified Rankin Scale score at 90 days) was analyzed by multivariate logistic regression analysis. Of the 257 included patients, 70 had a good outcome at 3 months. PPV from admission through the first 24 h after IAT was independently associated in a graded manner with poor outcome [multivariable-adjusted odds ratios (95% confidence interval) for the highest of PPV were 43.0 (8.7–212.8) for SD, 40.3 (9.8–165.0) for CV, 55.0 (11.2–271.2) for SV, and 40.1 (8.0–201.9) for ΔBP]. The area under the receiver operating characteristic curve (95% confidence interval) of the PPV parameters were 0.924 (0.882–0.965) for SD, 0.886 (0.835–0.938) for CV, 0.932 (0.891–0.973) for SV, and 0.892 (0.845–0.939) for ΔBP, and the Youden index values were 0.740, 0.633, 0.759, and 0.756, respectively. In summary, BPV from admission through the first 24 h after IAT was independently associated with poor outcome at 3 months in patients with LVO, with greater variability corresponding to a stronger association. Thus, PPV may be a clinically useful predictor of functional prognosis in LVO patients treated with IAT.

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.

Prognostic significance of early systolic blood pressure variability after endovascular thrombectomy and intravenous thrombolysis in acute ischemic stroke: A systematic review and meta-analysis

OBJECTIVES

Previous studies have shown inconsistent results regarding the effect of early systolic blood pressure variability (SBPV) after endovascular thrombectomy (EVT) and intravenous thrombolysis (IVT) on functional outcome in acute ischemic stroke (AIS). The systematic review and meta-analysis aimed to determine the effect of early SBPV after EVT and IVT on outcome in AIS.

MATERIALS AND METHODS

We searched for articles published before February 2020 in the following databases: PubMed, Web of Science, EMBASE, Medline, and Google Scholar. The pooled multivariate odds ratios (ORs) or relative risks (RRs) and 95% confidence intervals (CIs) were obtained using STATA 13.0 software.

RESULTS

Increased early SBPV after EVT was significantly associated with worse functional outcome in AIS (OR = 1.42, 95% CI 1.02 to 1.99, I²  = 82.4%, p value of Q test < .001), whereas no significant associations were indicated between SBPV after IVT and functional outcome, symptomatic intracerebral hemorrhage (sICH) in AIS [functional outcome: RR = 1.08, 95% CI 0.96 to 1.22, I²  = 0.0%, p value of Q test = 0.793; sICH: RR = 2.40, 95% CI 0.71 to 8.03, I²  = 78.2%, p value of Q test = 0.01].

CONCLUSIONS

The present study provided evidence that increased early SBPV after EVT is related to worse longer-term functional outcome in AIS, but the association is not significant in AIS patients treated with IVT. Furthermore, individualized BP management strategies were essential for AIS patients after EVT or IVT.

Impact of Blood Pressure After Successful Endovascular Therapy for Anterior Acute Ischemic Stroke: A Systematic Review

Background and Purpose: Optimal blood pressure (BP) targets after endovascular therapy (EVT) for acute ischemic stroke (AIS) still need to be assessed, especially according to the recanalization status. Facing the lack of randomized controlled trials addressing this question, we performed a systematic review of studies assessing the post-EVT BP impact on functional outcome and symptomatic intracranial hemorrhage (sICH). Methods: Studies published after January 1, 2012 were included in the systematic review. The PRISMA checklist and flow diagram were followed for the design and reporting of this work. Results: Five studies were included in the present analysis. Despite a significant heterogeneity among studies which precluded a meta-analysis, systolic BP (SBP) was the most frequently used parameter to describe BP. BP variability (standard deviation, successive variability) after EVT was associated with worse functional outcome, especially in studies without specific BP targets after successful EVT. Lower BP values after successful EVT were associated with lower odds of sICH. Four studies evaluated the post-EVT BP impact on recanalized patients solely, with only one specifically addressing the impact of a TICI 2B vs. 2C. Interestingly, SBP reduction was inversely associated with worse outcomes in TICI 3 patients but not in TICI 2B patients, pointing to the potential value of BP management according to the exact TICI. Conclusions: BP post-EVT seems to be associated with worse functional outcomes and sICH. However, given the important heterogeneity depicted among the included studies, no decisive conclusion can be made from this systematic review, thus underlying the urgent need of randomized controlled trials evaluating this question.

Blood Pressure Management Following Large Vessel Occlusion Strokes: A Narrative Review

Stroke is one of the leading causes of morbidity and mortality worldwide. Intravenous tissue plasminogen activator and mechanical thrombectomy comprise the two major treatments for acute ischemic stroke. Tissue plasminogen activator has been used for more than two decades and guidelines for hemodynamic management following tissue plasminogen activator administration are well established. However, mechanical thrombectomy is a relatively newer therapy and there is a paucity of evidence regarding hemodynamic management following large vessel occlusion strokes. The important tenets guiding the pathophysiology of large vessel occlusion strokes include understanding of cerebral autoregulation, collateral circulation, and blood pressure variability. In this narrative review, we discuss the current American Heart Association-American Stroke Association guidelines for the early management of acute ischemic stroke during different phases of the illness, encountered at different sections of a hospital including the emergency room, the neuro-interventional suite, and the intensive care unit. There is emerging evidence with regard to post-recanalization blood pressure management following large vessel occlusion strokes. Future research directions will include rea-ltime blood pressure variability assessments, identifying the extent of impaired autoregulation, and providing guidelines related to range and personalized blood pressure trajectories for patients following large vessel occlusion strokes.

Association of Blood Pressure With Outcomes in Acute Stroke Thrombectomy

Limited data exist evaluating the effect of blood pressure (BP) on clinical outcomes among patients with acute ischemic stroke with large vessel occlusion treated with mechanical thrombectomy (MT). We sought to evaluate the association of BP levels on clinical outcomes among patients with acute ischemic stroke with large vessel occlusion treated with MT. Studies were identified that reported the association of systolic BP (SBP) or diastolic BP levels before, during, or after MT on the outcomes of patients with acute ischemic stroke treated with MT. Unadjusted and adjusted analyses of studies reporting odds ratios (OR_adj) per 10 mm Hg BP increment were performed. Our analysis included 25 studies comprising 6474 patients. Higher pre-MT mean SBP (P=0.008) and post-MT maximum SBP (P=0.009) levels were observed in patients who died within 3 months. Patients with 3-month functional independence were noted to have lower pre-MT (P<0.001) and post-MT maximum SBP levels (P<0.001). In adjusted analyses, increasing post-MT maximum SBP and diastolic BP levels were associated with 3-month mortality (OR_adj, 1.19 [95% CI,1.00-1.43]; I²=78%, P value for Cochran Q test: 0.001) and symptomatic intracranial hemorrhage (OR_adj, 1.65 [95% CI, 1.11-2.44]; I²=0%, P value for Cochran Q test: 0.80), respectively. Increasing pre- and post-MT mean SBP levels were associated with lower odds of 3-month functional independence (OR_adj, 0.86 [95% CI, 0.77-0.96]; I²=18%, P value for Cochran Q test: 0.30) and (OR_adj, 0.80 [95% CI, 0.72-0.89]; I²=0%, P value for Cochran Q test: 0.51), respectively. In conclusion, elevated BP levels before and after MT are associated with adverse outcomes among patients with acute ischemic stroke with large vessel occlusion.