Blood Pressure Goals and Clinical Outcomes after Successful Endovascular Therapy: A Multicenter Study

Blood pressure management based on infarct volume after successful endovascular thrombectomy

INTRODUCTION

While the efficacy of endovascular thrombectomy (EVT) in large core infarcts has been established, the influence of blood pressure (BP) management on functional outcomes based on infarct volume remains unclear.

PATIENTS AND METHODS

We conducted a secondary analysis of the Outcome in Patients Treated With Intra-Arterial Thrombectomy-Optimal Blood Pressure Control (OPTIMAL-BP) trial, which compared intensive (systolic BP < 140 mmHg) versus conventional (systolic BP 140-180 mmHg) BP management within the first 24 h following successful recanalization. Patients were grouped based on an infarct volume cut-off of 50 ml, assessed 24 h post-EVT. The primary efficacy outcome was functional independence (modified Rankin Scale of 0-2) at 3 months. Change of predicted probability for functional independence between BP managements, as infarct volume varied, was assessed.

RESULTS

Of the 300 patients, 222 (74.0%) were in the infarct volume ⩽50 ml group and 78 (26.0%) were in the infarct volume >50 ml group. The conventional management was significantly associated with a higher rate of functional independence in the infarct volume ⩽50 ml group (adjusted odds ratio [AOR], 2.06 [95% CI, 1.12-3.86]). In the infarct volume >50 ml group, the proportion of patients with functional independence was not significantly different between BP managements (AOR, 1.52 [95% CI, 0.46-5.04]). The interaction effect between the infarct volume groups and BP managements was not significant. As infarct volume increased, the difference in predicted probability of functional independence between BP managements decreased.

DISCUSSION AND CONCLUSIONS

Conventional BP management showed greater benefits for achieving functional independence at 3 months when infarct volumes were smaller. As infarct volume increased, the impact of BP management strategies on functional outcomes decreased.

REGISTRATION

ClinicalTrials.gov (NCT04205305).

Magnitude of systolic blood pressure reduction following endovascular treatment and clinical outcomes in acute large artery occlusion stroke

BACKGROUND

The impact of lowering systolic blood pressure (SBP) following endovascular treatment (EVT) in acute large vessel occlusion stroke (LVOS) patients remains unclear. We aimed to explore the effect of the magnitude of SBP reduction (SBPr) after EVT on outcomes in LVOS patients.

METHODS

We consecutively registered patients at three comprehensive stroke centres who had experienced EVT as a result of acute anterior circulation LVOS. SBPr was calculated as follows: (baseline SBP-mean SBP/baseline SBP)×100%. The 90-day modified Rankin Scale score ranging from 0 to 2 was defined as a favourable functional outcome. Based on CT scans obtained within 24 hours after procedure, symptomatic intracranial haemorrhage (sICH) was assessed according to the criteria of the European Cooperative Acute Stroke Study III.

RESULTS

We enrolled 1080 patients, of which 908 (84.1%) had successful recanalisation. In the overall cohort, SBPr was correlated with lower odds of sICH (SBPr±10% as a reference, 20%-30%: OR 0.460; 95% CI: 0.245 to 0.864; p=0.016; >30%: OR 0.304; 95% CI 0.123 to 0.749; p=0.010). In patients who achieved successful reperfusion, SBPr>30% was correlated with higher odds of a poor outcome (SBPr±10% as a reference, OR 2.150; 95% CI 1.268 to 3.645; p=0.004) and SBPr has a similar tendency towards reducing the incidence of sICH. In the subgroup analyses, baseline Alberta Stroke Programme Early CT (ASPECT) score (pinteract=0.024) modified the effect of SBPr on the 90-day outcome.

CONCLUSION

Among patients with EVT, a significant drop in SBP may be related to a poor functional outcome and a reduced incidence of sICH. Baseline ASPECT score may be an important interacting factor in the association of SBPr with the 90-day outcome. This study provides new insights for individualised BP management in patients with EVT.

Flow restoration during mechanical thrombectomy for large vessel occlusion is associated with an immediate reduction of systemic blood pressure

INTRODUCTION

Managing blood pressure in patients with large vessel occlusion affects infarct size and clinical outcomes. We examined how restoring blood flow impacts systemic blood pressure during mechanical thrombectomy.

PATIENTS AND METHODS

Patients with large vessel occlusion in the anterior circulation undergoing mechanical thrombectomy between June 2016 and January 2018 were screened. We included those treated under local anesthesia or conscious sedation and analyzed standardized anesthesia protocols to assess systolic and diastolic blood pressure levels throughout the procedure. The primary outcome was the change of blood pressure, compared 5 min before versus 5 min after the last recanalization attempt. Successful reperfusion was defined as Thrombolysis in Cerebral Infarction score ⩾ 2b.

RESULTS

Of 134 patients, 117 (87%) achieved successful angiographic reperfusion, showing a notable systolic blood pressure drop 5 min after flow restoration (10.2 ± 14.6 vs 3.24 ± 8.65 mm Hg, p = 0.009). Successful angiographic reperfusion was a significant predictor for this decrease in multivariable logistic regression: OR = 1.34 (95% CI: 1.03-1.73, p = 0.0299). Among 66 patients not given circulation-affecting meds, a significant systolic pressure reduction was also observed (155 ± 17 mm Hg to 148 ± 17 mm Hg ; p < 0.001). No diastolic pressure changes were significant.

DISCUSSION AND CONCLUSIONS

Flow restoration was associated with an immediate reduction of systolic blood pressure values in patients undergoing mechanical recanalization under local anesthesia or conscious sedation. This suggests a complex interplay between endovascular stroke therapy and cardiovascular hemodynamics.

Meta-Analysis of the Safety and Efficacy of Intensive Blood Pressure Control After Thrombectomy

PURPOSE

After successful endovascular treatment of acute ischemic stroke, there remains considerable controversy surrounding the efficacy of intensified blood pressure control therapy. Presently, numerous randomized controlled trials have yielded diverse findings. Thus, our objective is to consolidate all current randomized controlled trial data to evaluate whether intensified systolic blood pressure targets, in comparison to standard targets, offer superior safety and efficacy.

METHODS

By searching the EMBASE, PubMed, and Cochrane Library databases, we identified randomized controlled trials comparing standard blood pressure control to intensified blood pressure control in patients with acute ischemic stroke undergoing endovascular thrombectomy (EVT). Efficacy outcomes included favorable clinical outcomes (defined as a modified Rankin Scale (mRS) score of 0-2 at 90 days), excellence clinical outcomes (defined as an mRS score of 0-1 at 90 days), and 90-day mortality. Safety outcomes included symptomatic intracranial hemorrhage (sICH). The relationship between standard and intensified blood pressure control post-EVT and the prognosis of patients with acute ischemic stroke undergoing endovascular thrombectomy was expressed using risk ratios (RR) and their corresponding 95% confidence intervals (95% CI).

RESULTS

The analysis encompassed four studies involving a total of 753 patients. After sensitivity analysis and exclusion of literature with significant heterogeneity, it was revealed that compared to intensified blood pressure control, standard blood pressure control was associated with excellent clinical outcomes RR of 0.81 (95% confidence interval [CI]: 0.73-0.90; p < 0.05; I2  =  25%). However, no significant correlation was found for favorable clinical outcomes, 90-day mortality, and safety outcomes including symptomatic intracranial hemorrhage.

CONCLUSIONS

After careful analysis, our conclusion is that intensified blood pressure control, compared to standard blood pressure control following endovascular treatment in acute stroke patients, does not yield better clinical outcomes and may even lead to inferior ones. Moreover, there is no significant disparity in terms of safety between the two approaches.

Advances in the Critical Care of Ischemic Brain Infarction

Acute care for ischemic stroke has dramatically evolved over the last years. Cerebral reperfusion is possible up to 24 h after symptoms onset. Advanced brain imaging allows identifying salvageable ischemic brain tissue, and the development of newer endovascular devices permits access to distal vessels. Monitoring for neurologic deterioration, diagnosis of stroke etiology, and secondary prevention treatments are important after initial treatment. This article reviews the recent advancements in the critical care of acute ischemic stroke.

Exploring the impact of intensive versus standard blood pressure management following post-endovascular therapy in ischemic stroke: A comparative systematic review and meta-analysis

Objective

This systematic review and meta-analysis examines the impact of intensive versus standard blood pressure control following post-endovascular therapy in ischemic stroke patients.

Methods

We conducted a systematic review and meta-analysis in accordance with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines by searching PubMed, Google Scholar, and Cochrane Central databases from inception to December 2023. The outcomes evaluated included symptomatic intracerebral hemorrhage, functional independence (modified Rankin Scale (mRS) score 0-2), death or disability (mRS score 3-6), and health-related quality of life (three-level EuroQoL five-dimensional self-report questionnaire (EQ-5D-3L score). We used the standard mean difference (SMD) with a 95% confidence interval (CI) for continuous outcomes in all studies and used a random-effects model for data synthesis irrespective of heterogeneity. Heterogeneity was assessed using the I2 statistics.

Results

We screened 2,000 articles and included four randomized controlled trials (3,635 patients). Intensive blood pressure control affected the health-related quality of life (EQ-5D-3L score) more than standard blood pressure (SMD = -0.22, 95% CI: -0.34 to -0.11, p = 0.0002). However, intensive blood pressure control after endovascular therapy did not significantly reduce the risk of intracerebral hemorrhage within 36 hours (risk ratio (RR) = 0.91, 95% CI: 0.70-1.19, p = 0.51). Additionally, there was an insignificant improvement in the likelihood of regaining functional independence (mRS score 0-2) at three months (RR = 0.87, 95% CI: 0.73-1.04, p = 0.12). Moreover, there was an insignificant increase in the risk of death or disability (mRS score 3-6) at 3 months with intensive blood pressure control compared to standard blood pressure control (RR = 1.18, 95% CI: 0.93-1.51, p = 0.18).

Conclusion

In summary, our findings indicate that implementing intensive blood pressure control does not lead to an increased risk of adverse outcomes such as intracranial hemorrhage within 36 hours, compromised functional independence, disability, or mortality 3 months following endovascular therapy. Despite the observed reduction in health-related quality of life reflected in the EQ-5D-3L score, the overall safety profile of intensive blood pressure control compared to standard management suggests its viability as a potential strategy for improving patient outcomes in the context of endovascular therapy.

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.

A Randomized Trial on Hemodynamic Optimization of Cerebral Perfusion after Successful Endovascular Therapy in Patients with Acute Ischemic Stroke (HOPE)

INTRODUCTION

In patients with acute ischemic stroke (AIS) secondary to intracranial large vessel occlusion, optimal blood pressure (BP) management following endovascular treatment (EVT) has not yet been established. The randomized trial on Hemodynamic Optimization of Cerebral Perfusion after Successful Endovascular Therapy in Patients with Acute Ischemic Stroke (HOPE) (clinicaltrials.gov id: NCT04892511) aims to demonstrate whether hemodynamic optimization using different systolic BP targets following EVT according to the degree of final recanalization, is more effective than currently recommended BP management in improving functional outcomes of patients with AIS.

METHODS

HOPE is an investigator-initiated multicenter clinical trial with randomized allocation, open-label treatment, and blinded endpoint evaluation (PROBE). Patients with an anterior circulation AIS within 24 h of symptom onset, treated with EVT, and showing successful recanalization (mTICI ≥2b) at the end of the procedure, are equally allocated (1:1) to hemodynamic optimization according to the study protocol versus BP management according to current guidelines (≤180/105 mm Hg). The protocol includes two different targets of systolic BP depending on the recanalization status (mTICI = 2b: 140-160 mm Hg; mTICI = 2c/3: 100-140 mm Hg). The protocol is applied within the first 72 h and includes BP lowering as well as vasopressor therapies when needed. The primary outcome is the proportion of favorable outcome (modified Rankin Scale [mRS] 0-2) at 90 days. Secondary outcomes include the shift on the mRS score, neurological deterioration, symptomatic intracerebral hemorrhage, and mortality.

CONCLUSION

The HOPE trial will provide new information on the safety and efficacy of different BP targets following EVT according to the degree of final recanalization in patients with AIS.

Blood pressure targets after successful reperfusion in mechanical thrombectomy for acute ischemic stroke: an updated systematic review and meta-analysis of randomized clinical trials

BACKGROUND

This study sought to determine whether intensive blood pressure (BP) control for patients with successful reperfusion following acute ischemic stroke (AIS) is beneficial, compared to conventional BP management.

METHODS

PubMed, Embase, and Cochrane databases were systematically searched for randomized controlled trials (RCTs) on the subject. The studied outcomes included dependency or death at 90 days (modified Rankin Scale [mRS] 3-6); severe disability at 90 days (mRS 3-5); mortality at 90 days; and symptomatic intracranial hemorrhage. Odds ratios (OR) with 95% confidence intervals were used to compare the treatment effects for categorical outcomes. We employed a fixed-effect model for analyses with low heterogeneity (I2 < 25%) and a random-effects model for analyses with higher heterogeneity.

RESULTS

A total of 1519 patients were included, with 50% (n = 760) receiving intensive BP control (systolic BP < 140 mmHg). Functional disability or death at 90 days was significantly higher in the intensive group (54.9%) compared to the conventional treatment group (44.1%) (OR = 1.51; 95% Confidence Interval [CI]: 1.15-1.96; p = 0.003; I2 = 29%). Severe functional disability (mRS 3-5) was significantly higher in the intensive group (30.6% vs. 43.5%, OR = 1.75; 95%CI = 1.36-2.25; p < 0.0001; I2 = 0%). There was no difference in symptomatic intracranial hemorrhage (OR = 1.13; 95%CI = 0.76-1.67) or mortality (OR = 1.22; 95%CI = 0.9-1.64).

CONCLUSIONS

Intensive BP control is harmful in patients who underwent EVT for AIS and achieved successful reperfusion. It yields higher rates of functional dependence, with no differences in mortality or symptomatic intracranial hemorrhage.

Systolic blood pressure reduction strategies in acute ischemic stroke patients following endovascular thrombectomy: a systematic review and meta-analysis

BACKGROUND AND AIMS

There is no clear consensus on ideal systolic blood pressure (SBP) target post-endovascular thrombectomy (EVT) in patients with acute ischemic stroke. This study intends to investigate the relationship between reducing SBP and clinical outcomes and to determine the therapeutic efficacy of moderate and intensive SBP reduction post EVT.

METHODS

A comprehensive search was conducted across five electronic databases to identify studies relevant to our analysis. Data from these studies were then analyzed using pooled relative risk (RR) along with their corresponding 95 % confidence intervals (CI) for our categorical outcomes. functional independence at 90 days post-EVT was defined as a modified Rankin score (mRS) 0-2.

RESULTS

Our meta-analysis included eight studies with 2922 patients: 1376 patients were treated with intensive SBP reduction, 306 with moderate SBP reduction, and 1243 with standard SBP reduction. There was no difference in the risk of functional independence at 90 days post-EVT with both intensive-SBP reduction (target 120-140 mmHg, relative risk (RR) =1.05, 95 % CI 0.82, 1.34, p = 0.72) and moderate-SBP reduction (>160 mm Hg) (RR= 0.95, 95 % CI 0.69, 1.31, p = 0.76) compared with standard SBP reduction (>180 mm Hg). The risk of symptomatic intracranial hemorrhage (sICH) did not significantly differ between standard-SBP reduction and intensive-SBP reduction (RR = 0.93, 95 % CI 0.66, 1.31, p = 0.36) or moderate-SBP reduction (0.72 (95 % CI [0.28, 1.87], p = 0.50) groups, respectively. Intensive-SBP reduction significantly decreased the risk of hemicraniectomy.

CONCLUSIONS

We did not identify any difference in functional independence at 90 days in acute ischemic stroke patients with either intensive-SBP reduction or moderate-SBP reduction compared with standard SBP reduction post-EVT.

Association of blood pressure and outcomes differs upon cerebral perfusion post-thrombectomy in patients with acute ischemic stroke

BACKGROUND

The relationship between post-endovascular thrombectomy (EVT) blood pressure (BP) and outcomes in patients with acute ischemic stroke (AIS) remains contentious. We aimed to explore whether this association differs with different cerebral perfusion statuses post-EVT.

METHODS

In a multicenter observational study of patients with AIS with large vessel occlusion who underwent EVT, we enrolled those who accepted CT perfusion (CTP) imaging within 24 hours post-EVT. We recorded post-EVT systolic (SBP) and diastolic BP. Patients were stratified into favorable perfusion and unfavorable perfusion groups based on the hypoperfusion intensity ratio (HIR) on CTP. The primary outcome was good functional outcome (90-day modified Rankin Scale score of ≤3). Secondary outcomes included early neurological deterioration, infarct size growth, and symptomatic intracranial hemorrhage.

RESULTS

Of the 415 patients studied (mean age 62 years, 75% male), 233 (56%) achieved good functional outcomes. Logistic regression showed that post-EVT HIR and 24-hour mean SBP were significantly associated with functional outcomes. Among the 326 (79%) patients with favorable perfusion, SBP <140 mmHg was associated with a higher percentage of good functional outcomes compared with SBP ≥140 mmHg (68% vs 52%; aOR 1.70 (95% CI 1.00 to 2.89), P=0.04). However, no significant difference was observed between SBP and functional outcomes in the unfavorable perfusion group. There was also no discernible difference between SBP and secondary outcomes across the different perfusion groups.

CONCLUSIONS

In patients with favorable perfusion post-EVT, SBP <140 mmHg was associated with good functional outcomes, which underscores the need for further investigations with larger sample sizes or a more individualized BP management strategy.

CLINICAL TRIAL REGISTRATION

ChiCTR1900022154.

Time-dependent systolic blood pressure within 72 h after endovascular treatment in large vessel occlusion stroke

BACKGROUND

The association of systolic blood pressure (SBP) and ischemic stroke outcome has recently been proved to be varied at different time points within 72 h after acute ischemic stroke onset; however, the specific status of how SBP affects prognosis at different time points within 72 h after endovascular treatment (EVT) among patients with large vessel occlusion (LVO) remains unclear.

METHODS

Consecutive LVO patients treated with EVT were enrolled in our study. BP data were collected at eight time points (1, 2, 4, 8, 16, 24, 48, and 72 h post-EVT). Outcome measure of interest was functional dependence, which was defined as mRS >2 at 90 days.

RESULTS

A total of 406 LVO patients treated with EVT from 2016 to 2022 were included. At 16 h after EVT, the relationship between SBP and functional dependence showed a nonlinear association. At other time points after EVT, SBP had linear relationships with functional dependence. Furthermore, higher SBP, as either a linear or quadratic term, had an adverse effect on functional outcome. In addition, three SBP trajectories were observed, and the high-to-low group was independently associated with functional dependence.

CONCLUSION

Taken together, higher SBP within the first 72 h after EVT has a time-dependent association with adverse clinical outcomes. Optimal blood pressure management during the first 72 h after EVT may be important to improve clinical outcome.

Standard Versus Intensive Blood Pressure Control in Acute Ischemic Stroke Patients Successfully Treated With Endovascular Thrombectomy: A Systemic Review and Meta-Analysis of Randomized Controlled Trials

BACKGROUND AND PURPOSE

The optimal blood pressure (BP) control after successful endovascular thrombectomy (EVT) in acute ischemic stroke (AIS) with large vessel occlusion (LVO) remains debatable. We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) that evaluate the efficacy and safety of standard BP control (with systolic BP ≤180 mm Hg) versus intensive BP control (systolic BP <140 mm Hg) during the 24 hours after successful EVT in AIS with LVO.

METHODS

PubMed, Scopus, the Cochrane Central Register of Controlled Trials, and Embase were searched to identify relevant trials. The crude odds ratio (OR) and 95% confidence interval (CI) were calculated and estimates using random-effects models were pooled. This meta-analysis followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines (PROSPERO ID: CRD42023450673).

RESULTS

Four RCTs involving 1,559 participants were included. Regarding efficacy outcomes, intensive BP control was associated with a lower likelihood of functional independence (OR: 0.68; 95% CI: 0.51-0.91 for modified Rankin Scale [mRS] ≤2) and walking without assistance (OR: 0.65; 95% CI: 0.53-0.81 for mRS ≤3). For safety outcomes, consistent with the efficacy findings, intensive BP control was significantly associated with severe disability or death (mRS 5 or 6) (OR: 1.34; 95% CI: 1.07-1.69). However, there were no significant differences including all-cause mortality, any intracerebral hemorrhage (ICH), symptomatic ICH, parenchymal hematoma type 2, and stroke recurrence.

CONCLUSION

While all four RCTs were conducted to demonstrate the superiority of intensive BP control over standard BP control, standard BP control may be beneficial for the outcome after EVT for AIS with LVO without increasing adverse safety outcomes. Caution should be needed with the application of intensive BP control during the 24 hours following successful recanalization after EVT.

Safety and efficacy of intensive systolic blood pressure lowering after successful endovascular therapy: a post hoc analysis of the BP TARGET trial

BACKGROUND

The Safety and Efficacy of Intensive Blood Pressure Lowering after Successful Endovascular Therapy in Acute Ischaemic Stroke (BP TARGET) trial demonstrated no benefit from intensive systolic blood pressure (SBP) treatment after successful reperfusion with endovascular therapy. However, it remains unknown if the response to blood pressure treatment is modified by other factors.

OBJECTIVE

To carry out a post hoc analysis of the BP TARGET trial data to determine if the response to blood pressure treatment is modified by factors such as age, history of hypertension, recanalization status, location of occlusion, diabetes, hyperglycemia, or pretreatment with intravenous thrombolysis.

METHODS

This is a post hoc analysis of the BP TARGET trial. Patients were divided into groups based on age, diabetes, blood glucose, site of occlusion, history of hypertension, and pretreatment with intravenous thrombolysis. The primary outcome was any intraparenchymal hemorrhage.

RESULTS

318 patients were included. Diabetes modified the treatment effect on favorable functional outcome (Pheteogenity=0.041). There was a trend towards benefit from intensive SBP treatment in diabetic patients (OR=2.81; 95% CI 0.88 to 8.88; p=0.08) but not in non-diabetic patients (OR=0.75; 95% 0.45 to 126; p 0.28). Age, location of occlusion, admission SBP, pretreatment with intravenous thrombolysis, and history of hypertension did not modify the effect of intensive SBP treatment on any of the outcomes.

CONCLUSION

The effect of SBP lowering treatment was not modified by age, location of occlusion history of hypertension, intravenous thrombolysis, and admission SBP. Diabetes modified the effect of intensive SBP lowering treatment, and there was a trend towards benefit from intensive SBP treatment in diabetic patients. This finding is hypothesis generating and requires further validation.

Association between blood pressure and endovascular treatment outcomes differs by baseline perfusion and reperfusion status

We hypothesized that the association between BP and endovascular treatment (EVT) outcomes would differ by baseline perfusion and recanalization status. We identified 388 ICA or M1 occlusion patients who underwent EVT ≤ 24 h from onset with successful recanalization (TICI ≥ 2b). BP was measured at 5-min intervals from arrival and during the procedure. Systolic BPs (SBP) were summarized as dropmax (the maximal decrease over two consecutive measurements), incmax (the maximal increase), mean, coefficient of variation (cv), and standard deviation. Adequate baseline perfusion was defined as hypoperfusion intensity ratio (HIR) ≤ 0.5; infarct proportion as the volume ratio of final infarcts within the Tmax > 6 s region. In the adequate perfusion group, infarct proportion was closely associated with SBPdropmax (β ± SE (P-value); 1.22 ± 0.48, (< 0.01)), SBPincmax (1.12 ± 0.33, (< 0.01)), SBPcv (0.61 ± 0.15 (< 0.01)), SBPsd (0.66 ± 0.08 (< 0.01)), and SBPmean (0.71 ± 0.37 (0.053) before recanalization. The associations remained significant only in SBPdropmax, SBPincmax, and SBPmean after recanalization. SBPincmax, SBPcv and SBPsd showed significant associations with modified Rankin Scale score at 3 months in the pre-recanalization period. In the poor perfusion group, none of the SBP indices was associated with any stroke outcomes regardless of recanalization status. BP may show differential associations with stroke outcomes by the recanalization and baseline perfusion status.

Hypertensive crisis: diagnosis, presentation, and treatment

PURPOSE OF REVIEW

Hypertensive crisis (HTN-C) is a condition of increasing prevalence. It carries significant morbidity and mortality, and prompt recognition and treatment are crucial. There is a paucity of controlled trials, so a working knowledge of the most recent literature in the area of HTN-C is helpful.

RECENT FINDINGS

Novel serological markers, including serum corin, have been found to aid in the early identification of end-organ damage from severely elevated blood pressure (BP). In the area of BP following thrombolysis for ischemic stroke, lower target BP (130-140 mmHg) is associated with some improved outcomes. Two large trials of lower BP following mechanical thrombectomy in stroke have failed to show improved outcomes; however, observed data show benefits at lower than currently recommended levels. Clevidipine, a calcium channel blocker marketed for unique use in HTN-C, was found to be noninferior to the generic less expensive nicardipine. Oral nifedipine was found to be the most effective agent for sustained BP reduction in preeclampsia.

SUMMARY

HTN-C remains an area with few prospective randomized trials, but there is active research on identifying lower goals for specific clinical scenarios. Ideal therapeutic agents should be tailored for specific end-organ damage.

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.

Good outcome associated with blood-brain barrier disruption and lower blood pressure after endovascular therapy

OBJECTIVES

To evaluate the association between post-endovascular thrombectomy (EVT) blood-brain barrier (BBB) disruption on MRI or CT and average systolic blood pressure (SBP) with favorable 90-day functional outcome. Observational studies have found elevated SBP associated with worse outcomes post-EVT, while recent randomized trials found no difference in targeted BP reduction. There may be a subgroup of patients who benefit from targeted BP reduction post-EVT.

METHODS

This is a single-center study of 1) anterior large vessel occlusion stroke patients treated with EVT from 2015 to 2021, 2) achieved mTICI grade 2b or 3. Hyperintense acute reperfusion marker (HARM), hemorrhagic transformation (HT), and midline shift at 3 h post-EVT and 24 h imaging were assessed independently by multiple raters. Binary logistic regression models were used to determine the association of post-EVT SBP with outcomes. BBB disruption was defined as HT or HARM on 3h post-EVT imaging.

RESULTS

Of 103 patients, those with SBP 100-129 versus SBP 130-160 found no significant difference in favorable 90-day outcome (64% vs. 46%, OR 2.11, 95% CI 0.78-5.76, p=0.143). However, among 71 patients with BBB disruption, a significant difference in favorable outcome of 64% in SBP 100-129 vs. 39% in SBP 130-160 group (OR 5.93, 95% CI 1.50-23.45, p=0.011) was found. There was no difference in symptomatic ICH, 90-day mortality, midline shift (≥5 mm), and hemicraniectomy, between BP or BBB groups.

CONCLUSIONS

BBB disruption on 3h post-EVT imaging and lower SBP was associated with favorable outcome. This imaging finding may guide targeted BP therapy and suggests need for a randomized control trial.

Increased blood pressure variability during general anaesthesia is associated with worse outcomes after mechanical thrombectomy: a prospective observational cohort study

OBJECTIVES

Optimal periprocedural blood pressure (BP) management during mechanical thrombectomy (MT) for acute ischaemic stroke is still controversial. The aim of this study was to investigate the association between intraprocedural BP variability (BPV) and outcomes in patients with large vessel occlusion (LVO) following MT with general anaesthesia.

DESIGN

A prospective observational cohort study.

SETTING

This study was conducted in a single tertiary hospital of Hangzhou in Zhejiang province.

PARTICIPANTS

A total of 141 patients with LVO treated with MT were finally included between January 2018 and September 2020.

MAIN OUTCOME MEASURES

Intraprocedural BP was recorded every 5 min throughout the procedure. BPV was measured as SD, coefficient of variation (CV), max-min (RANGE) and successive variation. Haemorrhagic transformation was assessed on 24-hour CT images according to European Cooperative Acute Stroke Study III trial. Poor functional outcome was defined as 90-day modified Rankin Scale score 3-6. Binary logistic regression analysis was used to investigate the association of BPV parameters with the incidence of parenchymal haemorrhage (PH) and poor functional outcome.

RESULTS

After controlling for age, female, history of smoking, hypertension and atrial fibrillation, baseline National Institutes of Health Stroke Scale, baseline systolic BP (SBP), baseline Alberta Stroke Program Early CT Score, bridging thrombolysis and times of retrieval attempts, the results demonstrated that intraprocedural SBP_RANGE (OR 1.029; 95% CI 1.003 to 1.055; p=0.027), SBP_SD (OR 1.135; 95% CI 1.023 to 1.259; p=0.017) and SBP_CV (OR 1.189; 95% CI 1.053 to 1.342; p=0.005) were independently associated with poor functional outcome. However, the independent association between intraprocedural BPV and PH at 24 hours has not been established in this study.

CONCLUSIONS

Increased intraprocedural BPV was more likely to have poor functional outcome in patients with LVO following MT with general anaesthesia. This finding indicates that special precautions should be taken to minimise BP fluctuation during procedure.

Acute Neurointervention for Ischemic Stroke

Acute ischemic stroke (AIS) is one of the major causes of death worldwide and a leading cause of disability. Until recently treatment of AIS was supportive, and in a minority of patients intravenous thrombolysis was available but with marginal clinical benefit. With the advent of stent retrievers, distal aspiration catheters as well as improved patient selection neurologic outcomes have greatly improved. However, the care of patients with AIS is still challenging and requires the early recognition of stroke symptoms, extensive diagnostic testing, early intervention, and advanced nursing and critical care.

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.

The Management of Hypertensive Emergencies-Is There a "Magical" Prescription for All?

Hypertensive emergencies (HE) represent high cardiovascular risk situations defined by a severe increase in blood pressure (BP) associated with acute, hypertension mediated organ damage (A-HMOD) to the heart, brain, retina, kidneys, and large arteries. Blood pressure values alone do not accurately predict the presence of HE; therefore, the search for A-HMOD should be the first step in the management of acute severe hypertension. A rapid therapeutic intervention is mandatory in order to limit and promote regression of end-organ damage, minimize the risk of complications, and improve patient outcomes. Drug therapy for HE, target BP, and the speed of BP decrease are all dictated by the type of A-HMOD, specific drug pharmacokinetics, adverse drug effects, and comorbidities. Therefore, a tailored approach is warranted. However, there is currently a lack of solid evidence for the appropriate treatment strategies for most HE. This article reviews current pharmacological strategies while providing a stepwise, evidence based approach for the management of HE.

Blood Pressure Trajectory Groups and Outcome After Endovascular Thrombectomy: A Multicenter Study

BACKGROUND

Elevated blood pressure after endovascular thrombectomy (EVT) has been associated with an increased risk of hemorrhagic transformation and poor functional outcomes. However, the optimal hemodynamic management after EVT remains unknown, and the blood pressure course in the acute phase of ischemic stroke has not been well characterized. This study aimed to identify patient subgroups with distinct blood pressure trajectories after EVT and study their association with radiographic and functional outcomes.

METHODS

This multicenter retrospective cohort study included consecutive patients with anterior circulation large-vessel occlusion ischemic stroke who underwent EVT. Repeated time-stamped blood pressure data were recorded for the first 72 hours after thrombectomy. Latent variable mixture modeling was used to separate subjects into five groups with distinct postprocedural systolic blood pressure (SBP) trajectories. The primary outcome was functional status, measured on the modified Rankin Scale 90 days after stroke. Secondary outcomes included hemorrhagic transformation, symptomatic intracranial hemorrhage, and death.

RESULTS

Two thousand two hundred sixty-eight patients (mean age [±SD] 69±15, mean National Institutes of Health Stroke Scale 15±7) were included in the analysis. Five distinct SBP trajectories were observed: low (18%), moderate (37%), moderate-to-high (20%), high-to-moderate (18%), and high (6%). SBP trajectory group was independently associated with functional outcome at 90 days (P<0.0001) after adjusting for potential confounders. Patients with high and high-to-moderate SBP trajectories had significantly greater odds of an unfavorable outcome (adjusted odds ratio, 3.5 [95% CI, 1.8-6.7], P=0.0003 and adjusted odds ratio, 2.2 [95% CI, 1.5-3.2], P<0.0001, respectively). Subjects in the high-to-moderate group had an increased risk of symptomatic intracranial hemorrhage (adjusted odds ratio, 1.82 [95% CI, 1-3.2]; P=0.04). No significant association was found between trajectory group and hemorrhagic transformation.

CONCLUSIONS

Patients with acute ischemic stroke demonstrate distinct SBP trajectories during the first 72 hours after EVT that have differing associations with functional outcome. These findings may help identify potential candidates for future blood pressure modulation trials.

Review of major trials of acute blood pressure management in stroke

Over the last two decades, there have been a number of major landmark clinical trials, classified as "major" as they sought to address clear clinical practice driven questions, in a pragmatic yet robust trial design, using a large powered sample size (n > 1000), in order to help improve patient outcome through informing guidelines. A commonality across all stroke sub-types included in these trials is the tendency to acute hypertensive crises within the acute stroke period. This phenomenon is associated with greater stroke complications and worsened overall prognosis. Multiple trials have attempted to address the issue of acute blood pressure management during the acute stroke period, with consideration for timing, magnitude of lowering, agent and relationship to other interventions. This review will consider the major clinical trials performed in ischaemic and haemorrhagic stroke that test the hypothesis that acute BP reduction improves clinical outcomes.

The Impact of Delayed Symptomatic Treatment Implementation in the Intensive Care Unit

We estimated the harm related to medication delivery delays across 12,474 medication administration instances in an intensive care unit using retrospective data in a large urban academic medical center between 2012 and 2015. We leveraged an instrumental variables (IV) approach that addresses unobserved confounds in this setting. We focused on nurse shift changes as disruptors of timely medication (vasodilators, antipyretics, and bronchodilators) delivery to estimate the impact of delay. The average delay around a nurse shift change was 60.8 min (p < 0.001) for antipyretics, 39.5 min (p < 0.001) for bronchodilators, and 57.1 min (p < 0.001) for vasodilators. This delay can increase the odds of developing a fever by 32.94%, tachypnea by 79.5%, and hypertension by 134%, respectively. Compared to estimates generated by a naïve regression approach, our IV estimates tend to be higher, suggesting the existence of a bias from providers prioritizing more critical patients.

Association between systolic blood pressure course and outcomes after stroke thrombectomy

Background

Systolic blood pressure (SBP) after endovascular thrombectomy (EVT) for large artery occlusive stroke is dynamic, requiring adaptable early prediction tools for improving outcomes. We investigated if post-EVT SBP course was associated with outcomes.

Methods

EVT-treated patients who had a stroke at Karolinska University Hospital, Stockholm, Sweden, were included in the study during 12 February 2018–11 February 2020. SBP was recorded during the first 24 hours after EVT. Primary outcome was functional independence defined by a Modified Rankin Scale score of 0–2 at 3 months. Secondary outcomes were death by 3 months, symptomatic intracranial haemorrhage and any intracranial haemorrhage. Patients with favourable outcomes were used as a reference SBP course in mixed linear effects models and compared with SBP courses of patients with unfavourable outcomes using the empirical best linear unbiased predictor, measuring deviations from the reference SBP course using the random effects. We tested model predictive stability for SBP measurements of only 18, 12 or 6 hours after EVT.

Results

374 patients were registered, with mean age 71, median NIHSS score of 15, and 53.2% men. Deviating from a linear SBP course starting at 130 mm Hg and decreasing to 123 mm Hg at 24 hours after EVT was associated with lower chances of functional independence (adjusted OR 0.53, 95% CI 0.29 to 0.88, for reaching either 99 or 147 mm Hg at 24 hours after EVT). All SBP course models for the remaining outcomes did not show statistical significance. Functional independence models showed stable predictive values for all time periods.

Conclusion

Deviating from a linear SBP course was associated with lower chances of 3-month functional independence.

Effect of blood pressure variability in the randomized controlled BP TARGET trial

BACKGROUND AND PURPOSE

The Blood Pressure Target in Acute Ischemic Stroke to Reduce Hemorrhage After Endovascular Therapy (BP TARGET) trial evaluated whether an intensive systolic blood pressure (SBP) target resulted in reduced rates of intracranial hemorrhage (ICH) after successful endovascular therapy (EVT) but did not assess the effect of blood pressure variability (BPV) on functional outcomes and ICH occurrence. We sought to evaluate this question in the BP TARGET trial.

METHODS

We performed a post hoc analysis of the BP TARGET trial and included patients with at least 50% of blood pressure (BP) recordings during the first 24 h after EVT. BPV parameters were SBP and diastolic BP (DBP) coefficient of variation (CV), standard deviation (SD), maximum-minimum (max-min), successive variation (SV), and time rate. The primary outcome was favorable functional outcome (3-month modified Rankin Scale between 0 and 2); the secondary outcome was the rate of ICH at 24 h.

RESULTS

We included 290 patients (mean number of BP measures = 30.4, SD = 8.0). BPV parameters (SBP_SD , SBP_max-min , SBP_CV ) were higher in the intensive SBP target group. Only DBP BPV parameters were associated with worse functional outcomes in the unadjusted model (DBP_SD , DBP_max-min , DBP_CV , and DBP_SV ), but not after adjustment. Higher SBP_max-min was associated with worse functional outcomes in Thrombolysis in Cerebral Infarction 2B patients (odds ratio [OR] = 0.62, 95% confidence interval [CI] = 0.38-1.02), but not in patients with complete reperfusion (OR = 1.27, 95% CI = 0.80-2.02, p for heterogeneity (p_het =0.037). None of the BPV parameters was associated with ICH, regardless of the randomization group or the reperfusion grade.

CONCLUSIONS

BPV was significantly higher in the intensive SBP target group but was not associated with functional outcome or ICH.

Blood Pressure After Endovascular Thrombectomy and Malignant Cerebral Edema in Large Vessel Occlusion Stroke

Background: Elevated blood pressure (BP) can cause blood–brain barrier disruption and facilitates brain edema formation. We aimed to investigate the association of BP level after thrombectomy with the development of malignant cerebral edema (MCE) in patients treated with endovascular thrombectomy (EVT).

Methods: Consecutive patients who underwent EVT for an anterior circulation ischemic stroke were enrolled from three comprehensive stroke centers. BP was measured hourly during the first 24 h after thrombectomy. MCE was defined as swelling causing a midline shift on the follow-up imaging within 5 days after EVT. Associations of various BP parameters, including mean BP, maximum BP (BP_max), and BP variability (BPV), with the development of MCE were analyzed.

Results: Of the 498 patients (mean age 66.9 ± 11.7 years, male 58.2%), 97 (19.5%) patients developed MCE. Elevated mean systolic BP (SBP) (OR, 1.035; 95% CI, 1.006–1.065; P = 0.017) was associated with a higher likelihood of MCE. The best SBP_max threshold that predicted the development of MCE was 165 mmHg. Additionally, increases in BPV, as evaluated by SBP standard deviation (OR, 1.061; 95% CI, 1.003–1.123; P = 0.039), were associated with higher likelihood of MCE.

Interpretation: Elevated mean SBP and BPV were associated with a higher likelihood of MCE. Having a SBP_max > 165 mm Hg was the best threshold to discriminate the development of MCE. These results suggest that continuous BP monitoring after EVT could be used as a non-invasive predictor for clinical deterioration due to MCE. Randomized clinical studies are warranted to address BP goal after thrombectomy.

Transcranial Doppler 6 h after Successful Reperfusion as a Predictor of Infarct Volume

OBJECTIVES

The aim of the study is to analyze the hemodynamic changes in the middle cerebral artery (MCA) after endovascular revascularization in acute ischemic stroke (AIS) due to large vessel occlusion and its association with the infarct volume size in the control head CT.

MATERIALS AND METHODS

Prospective study of patients with AIS due to internal carotid artery terminus or M1 segment of the MCA occlusion, who underwent endovascular treatment with a final TICI 2b-3 score, without concomitant stenosis ≥50% in both cervical carotid arteries. Transcranial Doppler ultrasound (TCD) of both MCAs was carried out at 6 h after the endovascular procedure. Mean flow velocities (MFV) after arterial reperfusion and its association with the infarct volume size in 24-36 h control head CT were determined.

RESULTS

91 patients (51 women) were included with a median age of 78 years and National institute of Health Stroke Scale of 18. The MCA was occluded in 76.92%, and intravenous thrombolysis was administered in 40.7%. The incidence of symptomatic intracranial hemorrhage was 5.5%. At three months, mortality was 19.8% and a 52.7% of patients achieved functional independence (modified Rankin Scale 0-2). After a multivariable logistic regression analysis, an increase in the MFV greater than 50% at 6 h in the treated MCA compared to contralateral MCA, was an independent predictor of large infarct volume in the control head CT with an OR 9.615 (95%CI: 1.908-47.620), p=0.006 CONCLUSIONS: Increased MFV assessed by TCD examination following endovascular recanalization is independently associated with larger infarct volume.

Overview of Acute Ischemic Stroke Evaluation and Management

Stroke is a major contributor to death and disability worldwide. Prior to modern therapy, post-stroke mortality was approximately 10% in the acute period, with nearly one-half of the patients developing moderate-to-severe disability. The most fundamental aspect of acute stroke management is "time is brain". In acute ischemic stroke, the primary therapeutic goal of reperfusion therapy, including intravenous recombinant tissue plasminogen activator (IV TPA) and/or endovascular thrombectomy, is the rapid restoration of cerebral blood flow to the salvageable ischemic brain tissue at risk for cerebral infarction. Several landmark endovascular thrombectomy trials were found to be of benefit in select patients with acute stroke caused by occlusion of the proximal anterior circulation, which has led to a paradigm shift in the management of acute ischemic strokes. In this modern era of acute stroke care, more patients will survive with varying degrees of disability post-stroke. A comprehensive stroke rehabilitation program is critical to optimize post-stroke outcomes. Understanding the natural history of stroke recovery, and adapting a multidisciplinary approach, will lead to improved chances for successful rehabilitation. In this article, we provide an overview on the evaluation and the current advances in the management of acute ischemic stroke, starting in the prehospital setting and in the emergency department, followed by post-acute stroke hospital management and rehabilitation.

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.

CE: Hypertensive Emergencies: A Review

ABSTRACT

While acute blood pressure elevations are commonly seen in the ED, not all require emergency treatment. True hypertensive emergencies are characterized by a rapid elevation in blood pressure to a level above 180/120 mmHg and are associated with acute target organ damage, which requires immediate hospitalization for close hemodynamic monitoring and IV pharmacotherapy. Recognizing the clinical signs and symptoms of hypertensive emergency, which may vary widely depending on the target organ involved, is critical. High blood pressure levels that produce no signs or symptoms of target organ damage may be treated without hospitalization through an increase in or reestablishment of previously prescribed oral antihypertensive medication. However, all patients presenting with blood pressure this high should undergo evaluation to confirm or rule out impending target organ damage, which differentiates hypertensive emergency from other hypertensive crises and is vital in facilitating appropriate emergency treatment. Drug therapy for hypertensive emergency is influenced by end-organ involvement, pharmacokinetics, potential adverse drug effects, and patient comorbidities. Frequent nursing intervention and close monitoring are crucial to recuperation. Here, the authors define the spectrum of uncontrolled hypertension; discuss the importance of distinguishing hypertensive emergencies from hypertensive urgencies; and describe the pathophysiology, clinical manifestations, and management of hypertensive emergencies.

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.

Acute Ischemic Stroke Associated with Myocardial Infarction: Challenges and Management

Acute ischemic stroke (AIS) and acute myocardial infarction (AMI) may co-occur simultaneously or in close temporal succession, with occurrence of one ischemic vascular event increasing a patient's risk for the other. Both employ time-sensitive treatments, and both benefit from expert consultation. Patients are at increased risk of stroke for up to 3 months following AMI, and aggressive treatment of AMI, including use of reperfusion therapy, decreases the risk of AIS. For patients presenting with AIS in the setting of a recent MI, treatment with alteplase, an intravenous tissue plasminogen activator, can be given, provided anterior wall myocardial involvement has been carefully evaluated. It is important for clinicians to recognize that troponin elevations can occur in the setting of AIS as well as other clinical scenarios and that this may have implications for short- and long-term mortality.

Magnitude of blood pressure change and clinical outcomes after thrombectomy in stroke caused by large artery occlusion

BACKGROUND

Extremes of both high and low systolic blood pressure (SBP) after mechanical thrombectomy (MT) in large artery occlusion stroke are known predictors of unfavorable outcome. However, the effect of SBP change (∆SBP) during the first 24 h on thrombectomy outcomes remains unclear. We aimed to investigate the association between ∆SBP at different time intervals and thrombectomy outcomes.

METHODS

We analyzed MT-treated patients registered in the SITS International Stroke Thrombectomy Registry from January 1, 2014 to September 3, 2019. Primary outcome was 3-month unfavorable outcome (modified Rankin scale scores 3-6). We defined ∆SBP as the mean SBP of a given time interval after MT (0-2, 2-4, 4-12, 12-24 h) minus admission SBP. Multivariable mixed logistic regression models were used to adjust for known confounders and center as random effect. Subgroup analyses were included to contrast specific subpopulations. Restricted cubic splines were used to model the associations.

RESULTS

The study population consisted of 5835 patients (mean age 70 years, 51% male, median NIHSS 16). Mean ∆SBP was -12.3, -15.7, -17.2, and -16.9 mmHg for the time intervals 0-2, 2-4, 4-12 h, and 12-24 h, respectively. Higher ∆SBP was associated with unfavorable outcome at 0-2 h (odds ratio 1.065, 95% confidence interval 1.014-1.118), 2-4 h (1.140, 1.081-1.203), 4-12 h (1.145, 1.087-1.203), and 12-24 h (1.145, 1.089-1.203), for every increase of 10 mmHg. Restricted cubic spline models suggested that increasing ∆SBP was associated with unfavorable outcome, with higher values showing increased risk of unfavorable outcome.

CONCLUSION

SBP increase after thrombectomy in large artery occlusion stroke is associated with poor functional outcome.

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.

Effect of Blood Pressure Management Strategies on Outcomes in Patients with Acute Ischemic Stroke After Successful Mechanical Thrombectomy

BACKGROUND

Variability, with no general consensus, exists in how patients' blood pressure should be managed after successful mechanical thrombectomy (MT) for large vessel ischemic stroke. We examined whether exceeding the systolic blood pressure (SBP) targets in patients during the first 24 hours after successful MT led to worse outcomes.

METHODS

We retrospectively studied a consecutive sample of adult patients who had undergone MT. We collected SBP data for the first 24 hours after MT and categorized the patients into 3 groups according to cases of the SBP exceeding 140, 160, or 180 mm Hg. The primary and secondary outcomes were the modified Rankin scale score at discharge and 90 days of follow-up, the incidence of symptomatic intracranial hemorrhage, malignant cerebral edema, and hemicraniectomy, mortality within 90 days, and discharge disposition.

RESULTS

A total of 117 patients were included (mean age, 65 ± 13.12 years; 53% female). The occurrence of ≥1 instance of SBP ≥180 mm Hg was significantly associated with poor functional outcomes at discharge (adjusted odds ratio [OR], 5.83; 95% confidence interval [CI], 1.41-32.9; P = 0.025) but not at 90 days of follow-up. The occurrence of SBP ≥160 mm Hg resulted in an independently increased odds of malignant cerebral edema (adjusted OR, 17.07; 95% CI, 2.56-174.4; P = 0.01), with a trend toward increased odds of symptomatic intracranial hemorrhage (adjusted OR, 4.42; 95% CI, 1.03-21.2; P = 0.0503).

CONCLUSIONS

These results suggest that individual instances of SBP elevation alone after successful MT, rather than a necessarily prolonged increased blood pressure as reflected by the mean or median SBP values, can significantly affect the clinical outcomes after successful MT.

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.

Thrombolysis in Cerebral Infarction 2b Reperfusions: To Treat or to Stop?

In patients undergoing mechanical thrombectomy, achieving complete (Thrombolysis in Cerebral Infarction 3) rather than incomplete successful reperfusion (Thrombolysis in Cerebral Infarction 2b) is associated with better functional outcome. Despite technical improvements, incomplete reperfusion remains the final angiographic result in 40% of patients according to recent trials. As most incomplete reperfusions are caused by distal vessel occlusions, they are potentially amenable to rescue strategies. While observational data suggest a net benefit of up to 20% in functional independence of incomplete versus complete reperfusions, the net benefit of secondary improvement from Thrombolysis in Cerebral Infarction 2b to 3 reperfusion might differ due to lengthier procedures and delayed reperfusion. Current strategies to tackle distal vessel occlusions consist of distal (microcatheter) aspiration, small adjustable stent retrievers, and administration of intra-arterial thrombolytics. While there are promising reports evaluating those techniques, all available studies show relevant limitations in terms of selection bias, single-center design, or nonconsecutive patient inclusion. Besides an assessment of risks associated with rescue maneuvers, we advocate that the decision-making process should also include a consideration of potential outcomes if complete reperfusion would successfully be achieved. These include (1) a futile angiographic improvement (hypoperfused territory is already infarcted), (2) an unnecessary angiographic improvement (the patient would not have developed infarction if no rescue maneuver was performed), and (3) a successful rescue maneuver with clinical benefit. Currently there is paucity of data on how these scenarios can be predicted and the decision whether to treat or to stop in a patient with incomplete reperfusion involves many unknowns. To advance the status quo, we outline current knowledge gaps and avenues of potential research regarding this clinically important question.

Blood pressure reduction and outcome after endovascular therapy: a secondary analysis of the BEST study

BACKGROUND

Elevated systolic blood pressure (SBP) in the acute phase after endovascular therapy (EVT) is associated with worse outcome. However, the association between systolic blood pressure reduction (SBPr) and the outcome of EVT is not well understood.

OBJECTIVE

To determine the association between SBPr and clinical outcomes after EVT in a prospective multicenter cohort.

METHODS

A post hoc analysis of the Blood Pressure after Endovascular Stroke Therapy (BEST) prospective observational cohort study was carried out. SBPr was defined as the absolute difference between admission SBP and mean SBP in the first 24 hours after EVT. Logistic regression was used to assess the association between SBPr and poor functional outcome (modified Rankin Scale score 3-6) at 90 days.

RESULTS

A total of 259/433 (58.5%) patients had poor outcome. SBPr was higher in the poor outcome group than in the good outcome group (26.6±27.4 vs 19.0±22.3 mm Hg; p<0.001). However, in adjusted models, SBPr was not independently associated with poor outcome (OR=1.00 per 1 mm Hg increase, 95% CI 0.99 to 1.01) or death (OR=0.9 per 1 mm Hg increase; 95% CI 0.98 to 1.00). No association remained when SBPr was divided into tertiles. Subgroup analyses based on history of hypertension, revascularization status, and antihypertensive treatment yielded similar results.

CONCLUSION

The reduction in baseline SBP following EVT was not associated with poor functional outcomes. Most of the cohort (88%) achieved successful recanalization, and therefore, these results mainly apply to patients with successful recanalization.