Evolution of Intra-arterial Therapy for Acute Ischemic Stroke in The Netherlands: MR CLEAN Pretrial Experience

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.

Advancements in diagnostic and interventional radiology for stroke treatment: the path from trial to bedside through the pre-MR CLEAN, MR CLEAN, and MR CLEAN II eras

The stroke field is inevitably connected with imaging in which radiologists fulfill a central role. Our landmark MR CLEAN trial led to the implementation of baseline computed tomography angiography or magnetic resonance angiography in the acute stroke workup and subsequent endovascular treatment (EVT) for ischemic stroke patients with a large vessel occlusion in the anterior circulation, resulting in numerous patients worldwide currently being treated often successfully. A reversal of the pathophysiologic process behind an acute cerebrovascular event was made possible. Subsequently, in the MR CLEAN II trials, the clinical impact of both diagnostic and interventional radiologists remained a cornerstone of our research, which means value-based radiology. Within these MR CLEAN II trials, we proved that aspirin and heparin during EVT should be avoided due to increased symptomatic intracranial hemorrhage risk (MR CLEAN-MED). We concluded there is additional benefit of EVT in the 6-to-24-h window after stroke in the presence of good collaterals on baseline CTA (MR CLEAN-LATE). The impactful success of our stroke trials that changed many guidelines was mainly attributable to (1) the societal burden of the disease, with two thirds of patients dying or being independent at 3 months; (2) the fact that stroke is a common disease, (3) the relatively simple and pragmatic approach of the trials resembling real-world setting; (4) the acceleration of implementation in clinical practice facilitated by a structured approach to guideline development and conditional funding; and foremost (5) the excellent collaboration on a professional level between-disciplines, i.e., diagnostic radiologists, interventionalists, and neurologists.Critical relevance statement The MR CLEAN and MR CLEAN II trials have had tremendous impact on clinical practice, directly by more patients being treated with an effective intervention and indirectly through adoption of evidence-based guidelines. It is in this setting of stroke treatment that diagnostic and interventional radiologists have played a crucial role and created clinical impact.

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.

A Bioinspired Manganese-Organic Framework Ameliorates Ischemic Stroke through its Intrinsic Nanozyme Activity and Upregulating Endogenous Antioxidant Enzymes

Following stroke, oxidative stress induced by reactive oxygen species (ROS) aggravates neuronal damage and enlarges ischemic penumbra, which is devastating to stroke patients. Nanozyme-based antioxidants are emerging to treat stroke through scavenging excessive ROS. However, most of nanozymes cannot efficiently scavenge ROS in neuronal cytosol and mitochondria, due to low-uptake abilities of neurons and barriers of organelle membranes, significantly limiting nanozymes' neuroprotective effects. To overcome this limitation, a manganese-organic framework modified with polydopamine (pDA-MNOF), capable of not only mimicking catalytic activities of natural SOD2's catalytic domain but also upregulating two endogenous antioxidant enzymes in neurons is fabricated. With such a dual anti-ROS effect, this nanozyme robustly decreases cellular ROS and effectively protects them from ROS-induced injury. STAT-3 signaling is found to play a vital role in pDA-MNOF activating the two antioxidant enzymes, HO1 and SOD2. In vivo pDA-MNOF treatment significantly improves the survival of middle cerebral artery occlusion (MCAo) mice by reducing infarct volume and more importantly, promotes animal behavioral recovery. Further, pDA-MNOF activates vascular endothelial growth factor expression, a downstream target of STAT3 signaling, thus enhancing angiogenesis. Taken together, the biochemical, cell-biological, and animal-level behavioral data demonstrate the potentiality of pDA-MNOF as a dual ROS-scavenging agent for stroke treatment.

Early post-endovascular treatment contrast extravasation on dual-energy CT is associated with clinical and radiological stroke outcomes: A 10-year single-centre experience

OBJECTIVE

To determine the association between early post-endovascular treatment (EVT) contrast extravasation (CE) on dual-energy CT (DECT) and stroke outcomes.

METHODS

EVT records in 2010-2019 were screened. Exclusion criteria included the occurrence of immediate post-procedural intracranial haemorrhage (ICH). Hyperdense areas on iodine overlay maps were scored according to the Alberta Stroke Programme Early CT Score (ASPECTS), thus forming a CE-ASPECTS. Maximum parenchymal iodine concentration and maximum iodine concentration relative to the torcula were recorded. Follow-up imaging was reviewed for ICH. The primary outcome measure was the modified Rankin Scale (mRS) at 90 days.

RESULTS

Out of 651 records, 402 patients were included. CE was found in 318 patients (79%). Thirty-five patients developed ICH on follow-up imaging. Fourteen ICHs were symptomatic. Stroke progression occurred in 59 patients. Multivariable regression showed a significant association between decreasing CE-ASPECTS and the mRS at 90 days (adjusted (a)cOR: 1.10, 95% CI: 1.03-1.18), NIHSS at 24-48 h (aβ: 0.57, 95% CI: 0.29-0.84), stroke progression (aOR: 1.14, 95% CI: 1.03-1.26) and ICH (aOR: 1.21, 95% CI: 1.06-1.39), but not symptomatic ICH (aOR 1.19, 95% CI: 0.95-1.38). Iodine concentration was significantly associated with the mRS (acOR: 1.18, 95% CI: 1.06-1.32), NIHSS (aβ: 0.68, 95% CI: 0.30-1.06), ICH (aOR: 1.37, 95% CI: 1.04-1.81) and symptomatic ICH (aOR: 1.19, 95% CI: 1.02-1.38), but not stroke progression (aOR: 0.99, 95% CI: 0.86-1.15). Results of the analyses with relative iodine concentration were similar and did not improve prediction.

CONCLUSIONS

CE-ASPECTS and iodine concentration are both associated with short- and long-term stroke outcomes. CE-ASPECTS is likely a better predictor for stroke progression.

Influence of the interventionist's experience on outcomes of endovascular thrombectomy in acute ischemic stroke: results from the MR CLEAN Registry

BACKGROUND

The relationship between the interventionist's experience and outcomes of endovascular thrombectomy (EVT) for acute ischemic stroke of the anterior circulation, is unclear.

OBJECTIVE

To assess the effect of the interventionist's level of experience on clinical, imaging, and workflow outcomes. Secondly, to determine which of the three experience definitions is most strongly associated with these outcome measures.

METHODS

We analysed data from 2700 patients, included in the MR CLEAN Registry. We defined interventionist's experience as the number of procedures performed in the year preceding the intervention (EXPfreq), total number of procedures performed (EXPno), and years of experience (EXPyears). Our outcomes were the baseline-adjusted National Institutes of Health Stroke Scale (NIHSS) score at 24-48 hours post-EVT, recanalization (extended Thrombolysis in Cerebral Infarction (eTICI) score ≥2B), and procedural duration. We used multilevel regression models with interventionists as random intercept. For EXPfreq and EXPno results were expressed per 10 procedures.

RESULTS

Increased EXPfreq was associated with lower 24-48 hour NIHSS scores (adjusted (a)β:-0.46, 95% CI -0.70 to -0.21). EXPno and EXPyears were not associated with short-term neurological outcomes. Increased EXPfreq and EXPno were both associated with recanalization (aOR=1.20, 95% CI 1.11 to 1.31 and aOR=1.08, 95% CI 1.04 to 1.12, respectively), and increased EXPfreq, EXPno, and EXPyears were all associated with shorter procedure times (aβ:-3.08, 95% CI-4.32 to -1.84; aβ:-1.34, 95% CI-1.84 to -0.85; and aβ:-0.79, 95% CI-1.45 to -0.13, respectively).

CONCLUSIONS

Higher levels of interventionist's experience are associated with better outcomes after EVT, in particular when experience is defined as the number of patients treated in the preceding year. Every 20 procedures more per year is associated with approximately one NIHSS score point decrease, an increased probability for recanalization (aOR=1.44), and a 6-minute shorter procedure time.

The Association between Hypoxia-Induced Low Activity and Apoptosis Strongly Resembles That between TTX-Induced Silencing and Apoptosis

In the penumbra of a brain infarct, neurons initially remain structurally intact, but perfusion is insufficient to maintain neuronal activity at physiological levels. Improving neuronal recovery in the penumbra has large potential to advance recovery of stroke patients, but penumbral pathology is incompletely understood, and treatments are scarce. We hypothesize that low activity in the penumbra is associated with apoptosis and thus contributes to irreversible neuronal damage. We explored the putative relationship between low neuronal activity and apoptosis in cultured neurons exposed to variable durations of hypoxia or TTX. We combined electrophysiology and live apoptosis staining in 42 cultures, and compared effects of hypoxia and TTX silencing in terms of network activity and apoptosis. Hypoxia rapidly reduced network activity, but cultures showed limited apoptosis during the first 12 h. After 24 h, widespread apoptosis had occurred. This was associated with full activity recovery observed upon reoxygenation within 12 h, but not after 24 h. Similarly, TTX exposure strongly reduced activity, with full recovery upon washout within 12 h, but not after 24 h. Mean temporal evolution of apoptosis in TTX-treated cultures was the same as in hypoxic cultures. These results suggest that prolonged low activity may be a common factor in the pathways towards apoptosis.

Oxygen-Generating Cyanobacteria Powered by Upconversion-Nanoparticles-Converted Near-Infrared Light for Ischemic Stroke Treatment

Stroke is one of most common causes of death and disability. Most of neuroprotective agents fail to rescue neurons from cerebral ischemic insults, mainly because of targeting downstream cascading events, such as excitotoxicity, oxidative and nitrosative stress, and inflammation, rather than improving hypoxia that initially occurs. Here, we report a near-infrared light (NIR)-driven nanophotosynthesis biosystem capable of generating oxygen and absorbing carbon dioxide, thus rescuing neurons from ischemia toward treating stroke. Through cerebral delivery of S. elongatus that spontaneously photosynthesize and upconversion nanoparticles (UCNPs), NIR with excellent tissue penetrating capability is converted to visible light by UCNPs to activate S. elongatus generating oxygen in vivo, enhancing angiogenesis, reducing infarction, and facilitating repair of brain tissues, thus improving neuronal function recovery. The combination of cell-biological, biochemical, and animal-level behavioral data provides compelling evidence demonstrating that this oxygen-generating biosystem through jointly utilizing microorganism and nanotechnology represents a novel approach to stroke treatment.

Path From Clinical Research to Implementation: Endovascular Treatment of Ischemic Stroke in the Netherlands

Before 2015, endovascular treatment (EVT) for acute ischemic stroke was considered a promising treatment option. Based on limited evidence, it was performed in several dedicated stroke centers worldwide on selected patients. Since 2015, EVT for patients with intracranial large vessel occlusion has quickly been implemented as standard treatment in many countries worldwide, supported by the revised international guidelines based on solid evidence from multiple clinical trials. We describe the development in use of EVT in the Netherlands before, during, and after the pivotal EVT trials. We used data from all patients who were treated with EVT in the Netherlands from January 2002 until December 2018. We undertook a time-series analysis to examine trends in the use of EVT using Poisson regression analysis. Incidence rate ratios per year with 95% CIs were obtained to demonstrate the impact and implementation after the publication of the EVT trial results. We made regional observation plots, adjusted for stroke incidence, to assess the availability and use of the treatment in the country. In the buildup to the MR CLEAN (Multicenter Clinical Trial of Endovascular Treatment of Acute Ischemic Stroke in the Netherlands), a slow increase of EVT patients was observed, with 0.2% of all ischemic stroke patients receiving EVT. Before the trial results were formally announced, a statistically significant increase in EVT-treated patients per year was observed (incidence rate ratio, 1.72 [95% CI, 1.46-2.04]), and after the trial publication, an immediate steep increase was seen, followed by a more gradual increase (incidence rate ratio, 2.14 [95% CI, 1.77-2.59]). In 2018, the percentage of ischemic stroke patients receiving EVT increased to 5.8%. A well-developed infrastructure, a pragmatic approach toward the use of EVT in clinical practice, in combination with a strict adherence by the regulatory authorities to national evidence-based guidelines has led to successful implementation of EVT in the Netherlands. Ongoing efforts are directed at further increasing the proportion of stroke patients with EVT in all regions of the country.

Intra-arterial neuroprotective therapy as an adjunct to endovascular intervention in acute ischemic stroke: A review of the literature and future directions

Mechanical thrombectomy for acute ischemic stroke due to large vessel occlusion has been shown to significantly improve outcomes. However, despite efficient rates of recanalization (60-90%), the rates of functional independence remain suboptimal (14-58%), most likely due to pathways of cell death in the brain that have already committed despite successful reperfusion. Pharmacologic neuroprotection provides a potential means of preventing this inevitable damage through targeting excitotoxicity, reactive oxygen species, cellular apoptosis, and inflammation. Numerous clinical trials using various neuroprotective agents have failed, but the majority of these trials did not include endovascular reperfusion, and thus the drugs were not reaching the therapeutic target. Intra-arterial delivery of neuroprotective agents via the guide catheter already in place for mechanical thrombectomy could provide a way to deliver high doses directly to the affected territory while limiting systemic exposure. Agents that have shown promise via the intra-arterial route in preclinical as well as some clinical models include magnesium sulfate, verapamil, cold saline, stem cells, and various combined approaches. Targeted hypothermia, achieved with intra-carotid infusion of cold saline, may provide an effective means of achieving hypothermia of the ischemic tissue while avoiding the systemic effects that have limited its use previously. Combination therapy of targeted hypothermia and a cocktail of drugs that provide anti-excitotoxic, anti-oxidant, anti-apopototic, and anti-inflammatory effects may provide an ideal approach that deserves further study in clinical trials.

Repeated Endovascular Thrombectomy in Patients With Acute Ischemic Stroke

Background and Purpose—

Patients with acute ischemic stroke treated with endovascular thrombectomy may be treated with repeat endovascular thrombectomy (rEVT) in case of recurrent large vessel occlusion. Data on safety and efficacy of these interventions is scarce. Our aim is to report on frequency, timing, and outcome of rEVT in a large nation-wide multicenter registry.

Methods—

In the Netherlands, all patients with endovascular thrombectomy have been registered since 2002 (MR CLEAN Pretrial registry, MR CLEAN Trial [Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands], and MR CLEAN Registry). We retrospectively reviewed these databases for anterior circulation rEVT cases. Patient characteristics, procedural data, and functional outcome (modified Rankin Scale at 90 days) were analyzed.

Results—

Of 3928 patients treated between 2002 and 2017, 27 (0.7%) underwent rEVT. Median time between first and second procedure was 78 (1–1122) days; 11/27 patients were re-treated within 30 days. Cardioembolism was the most common etiology (18 patients [67%]). In 19 patients (70%), recurrent occlusion occurred ipsilateral to previous occlusion. At 90 days after rEVT procedure, 44% of the patients had achieved functional independence (modified Rankin Scale score of 0–2), and 33% had died. Adverse events were 2/27 (7.4%) intracranial hemorrhage, 1/27 (3.7%) stroke progression, and 1/27 (3.7%) pneumonia.

Conclusions—

In this large nationwide cohort of patients with acute ischemic stroke treated with endovascular thrombectomy, rEVT was rare. Stroke cause was mainly cardio-embolic, and most recurrent large vessel occlusions in which rEVT was performed occurred ipsilateral. Although there probably is a selection bias on repeated treatment in case of recurrent large vessel occlusion, rEVT appears safe, with similar outcome as in single-treated cases.

Validation of the extended thrombolysis in cerebral infarction score in a real world cohort

Background

A thrombolysis in cerebral infarction (TICI) score of 2b is defined as a good recanalization result although the reperfusion may only cover 50% of the affected territory. An additional mTICI2c category was introduced to further differentiate between mTICI scores. Despite the new mTICI2c category, mTICI2b still covers a range of 50–90% reperfusion which might be too imprecise to predict neurological improvement after therapy.

Aim

To compare the 7-point “expanded TICI” (eTICI) scale with the traditional mTICI in regard to predict functional independence at 90 days.

Methods

Retrospective review of 225 patients with large artery occlusion. Angiograms were graded by 2 readers according the 7-point eTICI score (0% = eTICI0; reduced clot = eTICI1; 1–49% = eTICI2a, 50–66% = eTICI2b50; 67–89% = eTICI2b67, 90–99% = eTICI2c and complete reperfusion = eTICI3) and the conventional mTICI score. The ability of e- and mTICI to predict favorable outcome at 90days was compared.

Results

Given the ROC analysis eTICI was the better predictor of favorable outcome (p-value 0.047). Additionally, eTICI scores 2b50, 2b67 and 2c (former mTICI2b) were significantly superior at predicting the probability of a favorable outcome at 90 days after endovascular therapy with a p-value of 0.033 (probabilities of 17% for mTICI2b50, 24% for mTICI2b67 and 54% for mTICI2c vs. 36% for mTICI2b).

Conclusions

The 7-point eTICI allows for a more accurate outcome prediction compared to the mTICI score because it refines the broad range of former mTICI2b results.

Intra-arterial verapamil post-thrombectomy is feasible, safe, and neuroprotective in stroke

Large vessel ischemic stroke represents the most disabling subtype. While t-PA and endovascular thrombectomy can recanalize the occluded vessel, good clinical outcomes are not uniformly achieved. We propose that supplementing endovascular thrombectomy with superselective intra-arterial (IA) verapamil immediately following recanalization could be safe and effective. Verapamil, a calcium channel blocker, has been shown to be an effective IA adjunct in a pre-clinical mouse focal ischemia model. To demonstrate translational efficacy, mechanism, feasibility, and safety, we conducted a group of translational experiments. We performed in vivo IA dose-response evaluation in our animal stroke model with C57/Bl6 mice. We evaluated neuroprotective mechanism through in vitro primary cortical neuron (PCN) cultures. Finally, we performed a Phase I trial, SAVER-I, to evaluate feasibility and safety of administration in the human condition. IA verapamil has a likely plateau or inverted-U dose-response with a defined toxicity level in mice (LD₅₀ 16-17.5 mg/kg). Verapamil significantly prevented PCN death and deleterious ischemic effects. Finally, the SAVER-I clinical trial showed no evidence that IA verapamil increased the risk of intracranial hemorrhage or other adverse effect/procedural complication in human subjects. We conclude that superselective IA verapamil administration immediately following thrombectomy is safe and feasible, and has direct, dose-response-related benefits in ischemia.

Protective roles of intra-arterial mild hypothermia and arterial thrombolysis in acute cerebral infarction

Objective

Herein, we evaluated the efficacy and safety of intra-arterial mild hypothermia in combination with arterial thrombolysis to treat acute cerebral infarction due to middle cerebral artery occlusion.

Methods

A total of 26 patients with acute middle cerebral artery occlusion were divided into a normothermia group (n = 15) and a mild hypothermia group (n = 11). The infarct volumes at 24 h and 7 days after the operation were compared between the normothermia group and the mild hypothermia group. Additionally, we compared neurological deficit scores between the two groups at 24 h, 7 days, and 1 mo after the operation.

Results

The infarct volumes and neurological deficit scores of the mild hypothermia group were significantly reduced compared to those in the normothermia group (p < 0.05). Furthermore, no adverse reactions or complications occurred in the mild hypothermia group.

Conclusion

Intra-arterial mild hypothermia reduced infarct volume after ischemia–reperfusion injury in the arterial thrombolysis of an acute cerebral infarction. Additionally, it improved the prognosis of patients with an acute middle cerebral artery occlusion, suggesting that this procedure is safe and effective for treating acute cerebral infarction.

The effect of age on outcome after intra-arterial treatment in acute ischemic stroke: a MR CLEAN pretrial study

Background

In recent randomized controlled trials (RCTs) intra-arterial treatment (IAT) has been proven effective and safe for patients with acute ischemic stroke (AIS). So far, there seemed to be no interaction between older age (>80) and main treatment effect. We studied the association of older age with outcome and adverse events after IAT in a cohort of intra arterially treated patients.

Methods and findings

Data from all AIS patients with proven proximal anterior circulation cerebral artery occlusion who were intra arterially treated between 2002 until the start of the MR CLEAN trial were studied retrospectively. Duration of the procedure, recanalization (Thrombolysis In Cerebral Infarction score (TICI)), early neurological recovery (i.e. decrease on NIHSS of ≥ 8 points) after one week or at discharge, good functional outcome at discharge by modified Rankin Scale (mRS ≤ 2) and the occurrence of neurological and non-neurological adverse events were assessed and the association with age was investigated. In total 315 patients met our inclusion criteria. Median age was 63 years (range 22–93) and 17 patients (5.4 %) were over 80. Age was inversely associated with good functional outcome (adjusted Odds Ratio (aOR) 0.80, 95 % CI: 0.66–0.98) for every 10 years increase of age. Age was not associated with longer duration of the procedure, lower recanalization rate or less early neurological recovery. The risk of all adverse events (aOR 1.27; 95 % CI: 1.08–1.50) and non-neurological adverse events (aOR 1.34; 95 % CI: 1.11–1.61) increased, but that of peri-procedural adverse events (aOR 0.79; 95 % CI: 0.66–0.94) decreased with age.

Conclusion

Higher age is inversely associated with good functional outcome after IAT in patients with AIS. However, treatment related adverse events are not related to age. These findings may help decision making when considering treatment of older patients with AIS.