Procedural blood pressure and contrast extravasation on dual energy computed tomography after endovascular stroke treatment

BACKGROUND

Blood brain barrier disruption (BBBD) can be visualized by contrast extravasation (CE) after endovascular treatment (EVT) in patients with acute ischemic stroke. Elevated blood pressure is a risk factor for BBBD. However, the association between procedural blood pressure and CE post-EVT is unknown.

METHODS

In this single-center retrospective study, we analyzed 501 eligible patients who received a dual energy CT (DECT) immediately post-EVT for acute ischemic stroke. Procedural blood pressure values (SBPmean, SBPmax, SBPmax-min, and MAPmean) were collected. CE was quantified by measuring the maximum parenchymal iodine concentration on DECT iodine overlay map reconstructions. As a measure for the extent of BBBD, we created CE-ASPECTS by deducting one point per hyperdense ASPECTS region on iodine overlay maps. The association between blood pressure and CE was assessed using multivariable linear regression.

RESULTS

The procedural SBPmean, SBPmax, and MAPmean were 150 ± 26 mmHg, 173 ± 29 mmHg, and 101 ± 17 mmHg, respectively. The median maximum iodine concentration on post-EVT DECT was 1.2 mg/ml (IQR 0.7-2.0), and median CE-ASPECTS was 8 (IQR 5-11). The maximum iodine concentration was not associated with blood pressure. SBPmean, SBPmax, and MAPmean were significantly associated with CE-ASPECTS (per 10 mmHg, β = -0.2, 95 % CI -0.31 to -0.09, β = -0.15, 95 % CI -0.25 to -0.06, β = -0.33, 95 % CI -0.49 to -0.17, respectively).

CONCLUSION

In acute ischemic stroke patients undergoing EVT, particularly in patients achieving successful recanalization, SBPmean, SBPmax, and MAPmean are associated with the extent of BBBD on immediate post-EVT DECT, but not with maximum iodine concentration.

Prognostic implications of intracranial haemorrhage on dual-energy CT immediately following endovascular treatment for acute ischemic stroke

OBJECTIVE

To describe the incidence, risk factors, and prognostic relevance of intracranial haemorrhage (ICH) immediately after endovascular treatment (EVT) for ischaemic stroke in the anterior circulation.

METHODS

EVT records from 2010 to 2019 were screened. Included patients underwent DECT within 3h post-EVT. Virtual native reconstructions were evaluated for ICH according to the Heidelberg criteria and grouped into Heidelberg classes (HCs): [HC1] haemorrhagic infarction (HI)1, HI2 and parenchymal haematoma (PH)1; [HC2] PH2; [HC3] i.a. intraventricular and subarachnoid haemorrhage. If ICH corresponding to multiple HCs was observed, we assumed that the (largest) parenchymal ICH would have the greatest prognostic impact. Hence, a single HC was attributed by the following order of severity: HC2, HC1, HC3. The primary outcome was the modified Rankin Scale (mRS) at 90 days. The effect of asymptomatic ICH (aICH) and symptomatic ICH (sICH) of (1) HC1 or HC2 and (2) HC3 on patient outcomes was evaluated with multivariable regression after multiple imputation.

RESULTS

Out of 651 records, 498 patients were included. Eighty-one (16%) patients showed ICH on post-EVT DECT, of which 19 were classified as HC1 (21% symptomatic), 6 as HC2 (100% symptomatic), and 56 as HC3 (14% symptomatic). ICH development was mainly associated with unfavourable procedural characteristics. Both aICH and sICH of HC1 or HC2 were associated with the mRS (aICH: adjusted [a]cOR 4.92, 95%CI [1.48-16.35]; sICH: acOR 12.97, 95%CI [2.39-70.26]) and mortality (aICH: aOR 10.08, 95%CI [2.48-40.88]; sICH: aOR 9.92, 95%CI [1.48-66.31]). Likewise, sICH of HC3 was associated with the mRS and mortality (acOR 19.91, 95%CI [4.03-98.35], and aOR 13.23, 95%CI [2.27-77.18], respectively). aICH of HC3 was not significantly associated with the mRS or mortality (acOR 0.87, 95%CI [0.48-1.57], and cOR 0.84, 95%CI [0.32-2.20], respectively).

CONCLUSIONS

Immediate post-EVT ICH is a frequent finding. Except for aICH of HC3, any ICH is associated with poor long-term clinical outcomes.

Comparison of Clinical and Radiological Outcomes Between Different (Balloon) Guide Catheter With and Without Inflated Balloon in Acute Ischemic Stroke Patients: A MaSQ-Registry Study

PURPOSE

Balloon guide catheters (BGCs) are used in endovascular treatment (EVT) for ischemic stroke. Previous literature did not distinguish between BGC use with and without inflated balloon. This study aims to compare outcomes between non-BCG and BGC use with and without inflated balloon during EVT.

METHODS

Patients who underwent EVT for anterior circulation ischemic stroke between September 2020 and February 2023 were analyzed. Patients were divided into three groups: non-BGC, BGC with inflated balloon, or BGC without inflated balloon. The primary outcome was the ordinal modified Rankin Scale (mRS) at 90-day follow-up. Secondary outcomes included expanded Thrombolysis In Cerebral Ischemia score (eTICI) and periprocedural complications. Regression analyses with BGC with inflated balloon as comparator were performed with adjustments. Subgroup analyses were conducted based on first-line thrombectomy technique.

RESULTS

Out of 511 patients, 428 patients were included. Compared to BCG with inflated balloon, the mRS at 90 days did not differ in the group without inflated balloon (adjusted common [ac]OR: 1.07, 95%CI 0.67-1.73) or non-BGC (acOR: 1.42, 95%CI 0.83-2.42). Compared to patients treated with a BGC with inflated balloon, those treated with BGC without inflated balloon had lower eTICI scores (acOR: 0.59, 95%CI 0.37-0.94), and patients treated with non-BGC had lower chances of periprocedural complications (aOR: 0.41, 95%CI 0.20-0.86).

CONCLUSIONS

This study shows no clinical differences in ischemic stroke patients treated with BGC with inflated balloon compared to non-BGC and BGC without inflated balloon, despite lower periprocedural complication rates in the non-BGC group and lower eTICI scores in the BGC without inflated balloon group.

LEVEL OF EVIDENCE

Level 3, non-controlled retrospective cohort study.

The correlation between CT perfusion deficits and immediate post-endovascular treatment contrast extravasation on dual energy CT in acute ischemic stroke patients

PURPOSE

After endovascular therapy (EVT) for ischemic stroke, post-EVT CT imaging often shows areas of contrast extravasation (CE) caused by blood brain barrier disruption (BBBD). Before EVT, CT-perfusion (CTP) can be used to estimate salvageable tissue (penumbra) and irrevocably damaged infarction (core). In this study, we aimed to correlate CTP deficits to CE, as a surrogate marker for BBBD, after EVT for ischemic stroke.

METHODS

In this single center study, EVT patients between 2010 and 2020 in whom both CTP at baseline and DECT post-EVT was performed were included. The presence of core and penumbra on CTP was assessed per ASPECTS region, resulting in a CTP-ASPECTScore and a CTP-ASPECTScore+penumbra. Likewise, CE on DECT was scored per ASPECTS region, resulting in a CE-ASPECTS. Correlation was assessed using Kendall's tau correlation and positive predictive values (PPV) were calculated per ASPECTS region. Bland-Altman plots were created to visualize the agreement between the two scores.

RESULTS

194 patients met our inclusion criteria. The median core and penumbra were 8 cc (IQR 1-25) and 103 cc (IQR 68-141), respectively. The median CTP-ASPECTScore, CTP-ASPECTScore+penumbra, and CE-ASPECTS were 7 (IQR 4-9), 3 (IQR 1-4), and 6 (IQR 4-9), respectively. The correlation between CTP-ASPECTScore and CE-ASPECTS was τ = 0.21, P <.001, and τ = 0.13, P =.02 between CTP-ASPECTScore+penumbra and CE-ASPECTS. Bland-Altman plots showed a mean difference (CTP-ASPECTS minus CE-ASPECTS) of 0.27 (95 %CI -6.7-7.2) for CTP-ASPECTScore and -3.2 (95 %CI -9.7-3.2) for CTP-ASPECTScore+penumbra. The PPVs of the CTP-ASPECTScore and CTP-ASPECTScore+penumbra were highest for the basal ganglia.

CONCLUSION

There is a weak although significant correlation between pre-EVT CTP-ASPECTS and post-EVT CE-ASPECTS. The weak correlation may be attributed to various imaging limitations as well as patient related factors.

Cost and Utility Estimates per Modified Rankin Scale Score up to 2 Years Post Stroke: Data to Inform Economic Evaluations From a Societal Perspective

OBJECTIVES

Model-based health economic evaluations of ischemic stroke are in need of cost- and utility estimates related to relevant outcome measures. This study aims to describe societal cost- and utility estimates per modified Rankin Scale (mRS)-score at different time points within 2 years post stroke.

METHODS

Included patients had a stroke between 3 months and 2.5 years ago. mRS and EQ-5D-5L were scored during a telephone interview. Based on the interview date, records were categorized into a time point: 3 months (3M; 3-6 months), 1 year (Y1; 6-18 months), or 2 years (Y2; 18-30 months). Patients completed a questionnaire on healthcare utilization and productivity losses in the previous 3 months. Initial stroke hospitalization costs were assessed. Mean costs and utilities per mRS and time point were derived with multiple imputation nested in bootstrapping. Cost at 3 months post stroke were estimated separately for endovascular treatment (EVT)-/non-EVT-patients.

RESULTS

1106 patients were included from 18 Dutch centers. At each time point, higher mRS-scores were associated with increasing average costs and decreasing average utility. Mean societal costs at 3M ranged from €11 943 (mRS 1, no EVT) to €55 957 (mRS 5, no EVT). For Y1, mean costs in the previous 3 months ranged from €885 (mRS 0) to €23 215 (mRS 5), and from €1655 (mRS 0) to €22 904 (mRS 5) for Y2. Mean utilities ranged from 0.07 to 0.96, depending on mRS and time point.

CONCLUSIONS

The mRS-score is a major determinant of costs and utilities at different post-stroke time points. Our estimates may be used to inform future model-based health economic evaluations.

Procedural Blood Pressure and Intracranial Hemorrhage on Dual-Energy Computed Tomography After Endovascular Stroke Treatment

PURPOSE

Optimal systolic blood pressure (SBP) management during endovascular treatment (EVT) for acute ischemic stroke remains a topic of debate. Though BP is associated with worse functional outcome, the relationship between BP and post-procedural intracranial hemorrhage (ICH) is less well-known. We aimed to investigate the association between BP during EVT and post-procedural ICH on dual-energy CT (DECT).

METHODS

We included all patients who underwent EVT for an anterior circulation large vessel occlusion between 2010 and 2019, and received DECT < 3 h post-EVT. All BP measurements during the EVT procedure were used to calculate mean arterial pressure (MAPmean), mean SBP (SBPmean), and SBPmax-min (highest minus lowest). ICH was assessed using virtual post-procedural unenhanced DECT reconstructions and classified as intraparenchymal or extraparenchymal. Symptomatic ICH was scored according to the Heidelberg criteria. The association between different BP parameters and ICH was assessed using multivariable logistic regression.

RESULTS

We included 478 patients. Seventy-six patients (16%) demonstrated ICH on DECT, of which 26 (34%) were intraparenchymal. Symptomatic intraparenchymal and extraparenchymal ICH occurred in 10 (38%) and 4 (8%) patients. SBPmax, SBPmean, and MAPmean were associated with intraparenchymal ICH with an adjusted odds ratio of 1.19 (95%CI, 1.02-1.39), 1.22 (95%CI, 1.03-1.46), and 1.40 (95%CI, 1.09-1.81) per 10 mmHg, while BP was not significantly associated with extraparenchymal ICH. BP did not differ between asymptomatic and symptomatic ICH.

CONCLUSION

Procedural BP is associated with intraparenchymal ICH on post-EVT DECT but not with extraparenchymal ICH. Future studies should evaluate whether individual procedural BP management reduces post-EVT ICH and improves clinical outcome.

Cerebral arterial air emboli on immediate post-endovascular treatment CT are associated with poor short- and long-term clinical outcomes in acute ischaemic stroke patients

PURPOSE

To determine the incidence and predictors of cerebral arterial air emboli (CAAE) on immediate post-endovascular treatment (EVT) dual-energy CT (DECT) in acute ischaemic stroke (AIS) patients, and describe their association with clinical outcomes.

METHODS

EVT records from 2010 to 2019 were screened. Exclusion criteria included intracerebral haemorrhage on post-EVT DECT. In the affected middle cerebral artery (MCA)-territory, circular and linear (length ≥ 1.5*width) CAAE were counted. Clinical data were collected from prospective records. The modified Rankin Scale (mRS) at 90 days was the primary outcome. Multivariable linear, logistic, and ordinal regression were used to analyse the effect of (1) linear CAAE and (2) isolated circular CAAE.

RESULTS

Out of 651 EVT-records, 402 patients were included. In 65 patients (16%), at least one linear CAAE was found in the affected MCA-territory. 17 patients (4%) showed isolated circular CAAE. Multivariable regression showed an association between both the presence and the number of linear CAAE and the mRS at 90 days (presence: adjusted (a)cOR 3.10, 95%CI 1.75-5.50; number: acOR 1.28, 95%CI 1.13-1.44), NIHSS at 24-48 h (presence: aβ 4.15, 95%CI 1.87-6.43; number: aβ 0.88, 95%CI 0.42-1.34), mortality at 90 days (presence: aOR 3.34, 95%CI 1.51-7.40; number: aOR 1.24, 95%CI 1.08-1.43) and stroke progression (presence: aOR 4.01, 95%CI 1.96-8.18; number: aOR 1.31, 95%CI 1.15-1.50). Isolated circular CAAE were not significantly associated with any outcome measure.

CONCLUSION

CAAE were found frequently on post-EVT CT imaging. The presence and the number of linear CAAE, but not circular CAAE, are associated with unfavourable short- and long-term clinical outcomes.

Endovascular treatment versus no endovascular treatment after 6-24 h in patients with ischaemic stroke and collateral flow on CT angiography (MR CLEAN-LATE) in the Netherlands: a multicentre, open-label, blinded-endpoint, randomised, controlled, phase 3 trial

BACKGROUND

Endovascular treatment for anterior circulation ischaemic stroke is effective and safe within a 6 h window. MR CLEAN-LATE aimed to assess efficacy and safety of endovascular treatment for patients treated in the late window (6-24 h from symptom onset or last seen well) selected on the basis of the presence of collateral flow on CT angiography (CTA).

METHODS

MR CLEAN-LATE was a multicentre, open-label, blinded-endpoint, randomised, controlled, phase 3 trial done in 18 stroke intervention centres in the Netherlands. Patients aged 18 years or older with ischaemic stroke, presenting in the late window with an anterior circulation large-vessel occlusion and collateral flow on CTA, and a neurological deficit score of at least 2 on the National Institutes of Health Stroke Scale were included. Patients who were eligible for late-window endovascular treatment were treated according to national guidelines (based on clinical and perfusion imaging criteria derived from the DAWN and DEFUSE-3 trials) and excluded from MR CLEAN-LATE enrolment. Patients were randomly assigned (1:1) to receive endovascular treatment or no endovascular treatment (control), in addition to best medical treatment. Randomisation was web based, with block sizes ranging from eight to 20, and stratified by centre. The primary outcome was the modified Rankin Scale (mRS) score at 90 days after randomisation. Safety outcomes included all-cause mortality at 90 days after randomisation and symptomatic intracranial haemorrhage. All randomly assigned patients who provided deferred consent or died before consent could be obtained comprised the modified intention-to-treat population, in which the primary and safety outcomes were assessed. Analyses were adjusted for predefined confounders. Treatment effect was estimated with ordinal logistic regression and reported as an adjusted common odds ratio (OR) with a 95% CI. This trial was registered with the ISRCTN, ISRCTN19922220.

FINDINGS

Between Feb 2, 2018, and Jan 27, 2022, 535 patients were randomly assigned, and 502 (94%) patients provided deferred consent or died before consent was obtained (255 in the endovascular treatment group and 247 in the control group; 261 [52%] females). The median mRS score at 90 days was lower in the endovascular treatment group than in the control group (3 [IQR 2-5] vs 4 [2-6]), and we observed a shift towards better outcomes on the mRS for the endovascular treatment group (adjusted common OR 1·67 [95% CI 1·20-2·32]). All-cause mortality did not differ significantly between groups (62 [24%] of 255 patients vs 74 [30%] of 247 patients; adjusted OR 0·72 [95% CI 0·44-1·18]). Symptomatic intracranial haemorrhage occurred more often in the endovascular treatment group than in the control group (17 [7%] vs four [2%]; adjusted OR 4·59 [95% CI 1·49-14·10]).

INTERPRETATION

In this study, endovascular treatment was efficacious and safe for patients with ischaemic stroke caused by an anterior circulation large-vessel occlusion who presented 6-24 h from onset or last seen well, and who were selected on the basis of the presence of collateral flow on CTA. Selection of patients for endovascular treatment in the late window could be primarily based on the presence of collateral flow.

FUNDING

Collaboration for New Treatments of Acute Stroke consortium, Dutch Heart Foundation, Stryker, Medtronic, Cerenovus, Top Sector Life Sciences & Health, and the Netherlands Brain Foundation.