Feasibility and Safety of Repeat Instant Endovascular Interventions in Patients with Refractory Cerebral Vasospasms

Stent Angioplasty for the Treatment of Cerebral Vasospasm: A Systematic Review and Meta-Analysis

BACKGROUND

Several case series and prospective cohorts have reported the use of stent retrievers (SR) and specifically designed expanding stents (ES) to perform in situ mechanical stent angioplasty to treat cerebral vasospasm in subarachnoid vasospasm.

PURPOSE

The aim of this study was to review and conduct a meta-analysis to evaluate the safety and efficacy of this novel technique.

DATA SOURCES

A systematic review and meta-analysis was conducted according to established protocols. Searches were conducted in PubMed, Scopus, Web of Science, and EMBASE databases up to June 2024, including variations of "stent," "expanding device," "vasospasm," "subarachnoid hemorrhage." Original studies reporting treatment outcomes for vasospasm by using SR/ES in more than 5 patients were included.

STUDY SELECTION

Pooled data from 8 studies, comprising 156 patients and 428 targeted vessels treated with stent angioplasty for vasospasm were analyzed.

DATA ANALYSIS

We evaluated rates of angiographic success, complications, recurrence, and neurologic improvement. Meta-analysis was performed by using a random-effects model.

DATA SYNTHESIS

The angiographic success rate was 81.8% (95% CI: 70.6-89.3). Subgroup analysis showed a success rate of 86.5% (95% CI: 62.6-96.1) with ES and 80.5% (95%CI: 62.6-93.1) with SR. Overall complication rate was 1.1% (95% CI: 0.0-3.6), due to clot formation or hemorrhage. Recurrence of vasospasm was noted in 12.8% (95% CI: 5.2-28.1) while neurologic improvement was seen in 65.9% (95% CI: 51.1-78.1) of the cases. Finally, it should be noted that all included studies used stent angioplasty in combination with intra-arterial vasodilators.

LIMITATIONS

Our meta-analysis is limited by selection and reporting biases, as well as high heterogeneity. Moreover, the overall low quality of available evidence is the main limitation of our results.

CONCLUSIONS

Combination of stent angioplasty and intra-arterial vasodilators was found to have high rates of angiographic success and low incidences of adverse events. Randomized controlled trials are needed to confirm their efficacy and safety compared with medical and balloon angioplasty treatments.

Risk Factors for Unfavorable Functional Outcome after Endovascular Treatment of Cerebral Vasospasm following Aneurysmal Subarachnoid Hemorrhage

BACKGROUND AND PURPOSE

Cerebral vasospasm remains a strong predictor of poor outcomes after aneurysmal subarachnoid hemorrhage (aSAH). Endovascular treatment of vasospasm can be considered when conservative treatment options are exhausted, but its superiority over standard treatment remains a subject of critical debate. This study focuses on patients with clinically relevant vasospasm after aSAH who underwent endovascular vasospasm treatment and aims to analyze patients' individual risk factors, intensity, and extent of cerebral vasospasm associated with poor functional outcomes after aSAH.

MATERIALS AND METHODS

We conducted a retrospective cohort study of consecutive patients with aSAH admitted at a tertiary stroke center between January 2016 and December 2022. Patients with medically refractory cerebral vasospasm necessitating at least 1 endovascular intervention were analyzed. Primary end point was defined as functional outcome defined as modified Rankin Scale (mRS) scores after 6 months. Secondary end point was the occurrence of cerebral infarctions following cerebral vasospasm.

RESULTS

Overall, 138 patients received endovascular treatment due to cerebral vasospasm, including 322 treatments, with 78 patients receiving more than 1 endovascular treatment. In 65.2% (90) of patients, cerebral vasospasm developed in both hemispheres; in 16.7% (23), cerebral vasospasm occurred involving the posterior circulation; and in 10.1% (14), percutaneous transluminal angioplasty was performed. Multivariable logistic regression analysis showed an association of higher age (adjusted odds ratio [aOR], 1.05, 95% CI: 1.0-1.1), higher Hunt and Hess grades (aOR, 2.12, 95% CI: 1.38-3.24), the occurrence of rebleeding (aOR, 4.97, 95% CI: 1.0-24.65), and bihemispheric vasospasm (aOR, 4.05, 95% CI: 1.4-11.72) with unfavorable outcome (mRS 3-6). Further analysis showed that higher age (aOR, 1.07, 95% CI: 1.03-1.13) was associated with an increased risk of developing vasospasm-associated infarctions.

CONCLUSIONS

Our results indicate an association between bihemispheric cerebral vasospasm and poor functional outcomes after aSAH. This finding supports a more aggressive treatment strategy in patients developing bihemispheric vasospasm to prevent unfavorable disease courses.

Management of neurological complications related to aneurysmal subarachnoid hemorrhage: A comparison of the bedside therapeutic algorithms

BACKGROUND

Aneurysmal subarachnoid hemorrhage (aSAH) is of the most serious emergencies in neurosurgical practice and continues to be associated with high morbidity and mortality. Beyond securing the ruptured aneurysm to prevent a rebleed, physicians continue to be concerned about potential complications such as cerebral vasospasm-delayed cerebral ischemia (DCI), an area where management remains highly variable. This study aimed at reviewing the most recent literature and assessing any up-to-date schemes for treating the most common aSAH neurological complications in adults that can be applied in daily clinical practice towards optimising outcomes.

METHODS

A systematic review was performed according to PRISMA guidelines on the management of aSAH neurological complications in adults. The literature surveyed was between 2016 and 2022 inclusive, using the Pubmed search engine. Comparisons between the methods suggested by existing therapeutic algorithms were discussed.

RESULTS

Six stepwise algorithms assisting the decision-making for treating cerebral vasospasm-DCI were recognised and compared. No algorithm was found for the management of any other neurological complications of aSAH. Despite differences in the algorithms, induced hypertension and endovascular therapy were common treatments in all approaches. Controversy in the therapeutic process of these complications surrounds not only the variability of methods but also their optimal application towards clinical outcome optimisation.

CONCLUSIONS

A universal approach to managing aSAH complications is lacking. Despite advances in the techniques to secure a ruptured aneurysm, there persist a high rate of neurological deficit and mortality, and several unanswered questions. More research is required towards stratification of current treatment algorithms as per the quality of their evidence.

Outcome analysis for patients with subarachnoid hemorrhage and vasospasm including endovascular treatment

As a complication of subarachnoid hemorrhage (SAH), vasospasm substantially contributes to its morbidity and mortality. We aimed at analyzing predictors of outcome for these patients including the role of endovascular treatment (ET). Our database was screened for patients with SAH treated in our Neuro-ICU from 2009 to 2019. Clinical parameters including functional outcome (modified Rankin Scale, mRS of 0-2 or 3-6 at discharge and after a median follow-up of 18 months) and details about ET were gathered on 465 patients, 241 (52%) of whom experienced vasospasm. Descriptive analyses were performed to identify explanatory variables for the dichotomized mRS score. A logistic regression model was fitted on 241 patients with vasospasm including age, Hunt and Hess Score, extraventricular drainage (EVD), forced hypertension, ET and delayed cerebral ischemia (DCI). The model found a Hunt and Hess Score of 5 (OR = 0.043, p = 0.008), requirement of EVD (OR = 0.161, p < 0.001), forced hypertension (OR = 0.242, p = 0.001), ET (OR = 0.431, p = 0.043) and DCI (OR = 0.229, p < 0.001) to be negative predictors of outcome while age was not. Use of intraarterial nimodipine alone (OR = 0.778, p = 0.705) or including balloon angioplasty (OR = 0.894, p = 0.902) and number of ETs per patient (OR = 0.757, p = 0.416) were not significant in a separate model with otherwise identical variables. While DCI is clearly associated with poor outcome, the influence of ET on outcome remains inconclusive. Limited by their retrospective nature and an indication bias, these data encourage a randomized assessment of ET.

Cervical Ganglion Sympathectomy to Treat Cerebral Vasospasm in Subarachnoid Hemorrhage

Delayed cerebral ischemia (DCI) is still a significant cause of death and disability after aneurysmal subarachnoid hemorrhage. Cerebral vasospasm represents one of the most reported mechanisms associated with DCI. The management of DCI-related vasospasm remains a significant challenge for clinicians; induced hypertension, intraarterial vasodilators, and/or intracranial vessel angioplasty-particularly in refractory or recurrent cases-are the most used therapies. Because an essential role in the pathophysiology of cerebral vasospasm has been attributed to the adrenergic sympathetic nerves, a "sympatholytic" intervention, consisting of a temporary interruption of the sympathetic pathways using local anesthetics, has been advocated to minimize the vascular narrowing and reverse the consequences of cerebral vasospasm on tissue perfusion. In this review, we have analyzed the existing literature on the block of the cervical ganglions, particularly the stellate ganglion, in managing refractory cerebral vasospasm in patients with aneurysmal subarachnoid hemorrhage. These findings could help clinicians to understand the potential role of such intervention and to develop future interventional trials in this setting.

Distal cerebral vasospasm treatment following aneurysmal subarachnoid hemorrhage using the Comaneci device: technical feasibility and single-center preliminary results

BACKGROUND

Balloon-assisted mechanical angioplasty for cerebral vasospasm following aneurysmal subarachnoid hemorrhage (aSAH) has a number of limitations, including transient occlusion of the spastic blood vessel. Comaneci is an FDA-approved device for temporary coil embolization assistance which has recently also been approved for the treatment of distal symptomatic refractory vasospasm. We aimed to report the feasibility, efficacy and safety of our experience with Comaneci angioplasty for refractory distal vasospasm (up to the second segment of the cerebral arteries) following aSAH.

METHODS

This is a retrospective analysis of a prospective series of 18 patients included between April 2019 and June 2021 with aSAH and symptomatic vasospasm refractory to medical therapy, who were treated using Comaneci-17-asssisted mechanical distal angioplasty. Immediate angiographic results, procedure-related complications, and clinical outcomes were assessed. Inter-rater reliability of the scores was determined using the intraclass correlation coefficient.

RESULTS

Comaneci-assisted distal angioplasty was performed in 18 patients, corresponding to 31 target arteries. All distal anterior segments were easily accessible with the Comaneci-17 device. Vasospasm improvement after Comaneci mechanical angioplasty was seen in 22 distal arteries (71%) (weighted Cohen's kappa (κ_w) 0.73, 95% CI 0.69 to 0.93). Vasospasm recurrence occurred in three patients (16.67%) and delayed cerebral infarction in three patients (16.67%), with a mean±SD delay between onset of symptoms and imaging follow-up (MRI/CT) of 32.61±8.93 days (κ_w 0.98, 95% CI 0.88 to 1).

CONCLUSION

This initial experience suggests that distal mechanical angioplasty performed with the Comaneci-17 device for refractory vasospasm following aSAH seems to be safe, with good feasibility and efficacy.

Incidence and Outcome of Peri-interventional Vasospasm During Endovascular or Microsurgical Treatment of Unruptured Intracranial Aneurysms

BACKGROUND

Peri-interventional vasospasm (PIVS) is associated with high risk of delayed cerebral vasospasm (DCVS), delayed cerebral ischemia, and poor outcome after aneurysmal subarachnoid hemorrhage. However, the incidence rate associated with treatment of unruptured intracranial aneurysm (UIA) remains unclear.

OBJECTIVE

To define the incidence and clinical significance of PIVS in UIA repair based on intraoperative/peri-interventional digital subtraction angiography.

METHODS

A consecutive series of 205 patients who underwent UIA treatment by means of microsurgical clipping (n = 109) or endovascular coil embolization (n = 96) was assessed for the occurrence of PIVS. In all cases, PIVS was detected, measured, and classified using intraoperative/peri-interventional digital subtraction angiography. Severity of PIVS, association of PIVS with the development of DCVS, and neurological outcome were analyzed.

RESULTS

Intraoperative PIVS was present in n = 14/109 (13%) patients with microsurgical clipping. Of these, caliber irregularities were mild (n = 10), moderate (n = 3), and severe (n = 1). In endovascularly treated patients, 6/96 (6%) developed PIVS, which were either mild (n = 3) or moderate (n = 3). Management in all cases included immediate intensive blood pressure management and application of topical papaverine or intra-arterial nimodipine immediately on detection of PIVS. No patient developed DCVS or lasting neurological deficits attributable to PIVS.

CONCLUSION

This series revealed a relatively high overall incidence of PIVS (10%). However, no association of PIVS with the development of DCVS or poor outcome was found. In contrast to ruptured intracranial aneurysms, PIVS in unruptured intracranial aneurysms-if immediately and adequately addressed-seems to be benign and without sequelae for patient's functional outcome.

Anesthesia care in the interventional neuroradiology suite: an update

PURPOSE OF REVIEW

The scope of procedures conducted by neurointerventionalists is expanding quickly, with lacking consensus over the best anesthesia modality. Although the procedures involve all age groups, the interventions may be complex and lengthy and may be provided in hospitals currently not yet familiar with the field. Here we review current literature addressing elective outpatient neurointerventional procedures and aim to provide an update on the management of intervention-specific crises, address special patient populations, and provide key learning points for everyday use in the neurointerventional radiology suite.

RECENT FINDINGS

Various studies have compared the use of different anesthesia modalities and preinterventional and postinterventional care. Monitored anesthesia care is generally recommended for elderly patients, whereas children are preferably treated with general anesthesia. Additional local anesthesia is beneficial for procedures, such as percutaneous kyphoplasty and vascular access.

SUMMARY

Combining different anesthetic modalities is a valuable approach in the neurointerventional radiology suite. More interventional and patient population-specific studies are needed to improve evidence-based perioperative management.

Intraarterial Nimodipine Versus Induced Hypertension for Delayed Cerebral Ischemia: A Modified Treatment Protocol

Background:

Rescue treatment for delayed cerebral ischemia (DCI) after subarachnoid hemorrhage can include induced hypertension (iHTN) and, in refractory cases, endovascular approaches, of which selective, continuous intraarterial nimodipine (IAN) is one variant. The combination of iHTN and IAN can dramatically increase vasopressor demand. In case of unsustainable doses, iHTN is often prioritized over IAN. However, evidence in this regard is largely lacking. We investigated the effects of a classical (iHTN+IAN) and modified (IAN only ) treatment protocol for refractory DCI in an observational study.

Methods:

Rescue treatment for DCI was initiated with iHTN (target >180 mm Hg systolic) and escalated to IAN in refractory cases. Until July 2018, both iHTN and IAN were offered in cases refractory to iHTN alone. After protocol modification, iHTN target was preemptively lowered to >120 mm Hg when IAN was initiated (IAN only ). Primary outcome was noradrenaline demand. Secondary outcomes included noradrenaline-associated complications, brain tissue oxygenation, DCI-related infarction and favorable 6-month outcome (Glasgow Outcome Scale 4–5).

Results:

N=29 and n=20 patients were treated according to the classical and modified protocol, respectively. Protocol modification resulted in a significant reduction of noradrenaline demand (iHTN+IAN 0.70±0.54 µg/kg per minute and IAN only 0.26±0.20 µg/kg per minute, P <0.0001) and minor complications (15.0% versus 48.3%, unadjusted odds ratio, 0.19 [95% CI, 0.05–0.79]; P <0.05) with comparable rates of major complications (20.0% versus 20.7%, odds ratio, 0.96 [0.23–3.95]; P =0.95). Incidence of DCI-related infarction (45.0% versus 41.1%, odds ratio, 1.16 [0.37–3.66]; P =0.80) and favorable clinical outcome (55.6% versus 40.0%, odds ratio, 1.88 [0.55–6.39]; P =0.32) were similar. Brain tissue oxygenation was significantly higher with IANonly (26.6±12.8, 39.6±15.4 mm Hg; P <0.01).

Conclusions:

Assuming the potential of iHTN to be exhausted in case of refractory hypoperfusion, additional IAN may serve as a last-resort measure to bridge hypoperfusion in the DCI phase. With close monitoring, preemptive lowering of pressure target after induction of IAN may be a safe alternative to alleviate total noradrenaline load and potentially reduce complication rate.

The Impact of Endovascular Rescue Therapy on the Clinical and Radiological Outcome After Aneurysmal Subarachnoid Hemorrhage: A Safe and Effective Treatment Option for Hemodynamically Relevant Vasospasm?

Objective

Cerebral vasospasm (CVS) represents one of the multiple contributors to delayed cerebral ischemia (DCI) in patients with aneurysmal subarachnoid hemorrhage (aSAH). Especially the management of CVS, refractory to medical treatment, is a challenging task during the acute phase after aSAH. Endovascular rescue therapies (ERT), such as medical and mechanical dilation, are possible treatment options on an individual basis. However, data about the influence on the patients' functional outcomes are limited. This study aims to assess the impact of ERT on the long-term functional outcome in aSAH-patients with refractory CVS.

Methods

We performed a retrospective analysis of aSAH patients treated between 2012 and 2018. CVS was considered refractory, if it persisted despite oral/intravenous nimodipine application and induced hypertension. The decision to perform ETR was made on an individual basis, according to the detection of “tissue at risk” on computed tomography perfusion (CTP) scans and CVS on computed tomography angiography (CTA) or digital subtraction angiography (DSA). The functional outcome was assessed according to the modified Rankin scale (mRS) 3 months after the ictus, whereas an mRS ≤ 2 was considered as a good outcome.

Results

A total of 268 patients were included. Out of these, 205 patients (76.5%) were treated without ERT (group 1) and 63 patients (23.5%) with ERT (group 2). In 20 patients (31.8%) balloon dilatation was performed, in 23 patients (36.5%) intra-arterial nimodipine injection alone, and in 20 patients (31.8%) both procedures were combined. Considering only the patient group with DCI, the patients who were treated with ERT had a significantly better outcome compared to the patients without ERT (Mann–Whitney test, p = 0.02).

Conclusion

Endovascular rescue therapies resulted in a significantly better functional outcome in patients with DCI compared to the patient group treated without ETR. CTP and CTA-based identification of “tissue at risk” might be a reliable tool for patient selection for performing ERT.

Inhaled Nitric Oxide Treatment for Aneurysmal SAH Patients With Delayed Cerebral Ischemia

Background

We demonstrated experimentally that inhaled nitric oxide (iNO) dilates hypoperfused arterioles, increases tissue perfusion, and improves neurological outcome following subarachnoid hemorrhage (SAH) in mice. We performed a prospective pilot study to evaluate iNO in patients with delayed cerebral ischemia after SAH.

Methods

SAH patients with delayed cerebral ischemia and hypoperfusion despite conservative treatment were included. iNO was administered at a maximum dose of 40 ppm. The response to iNO was considered positive if: cerebral artery diameter increased by 10% in digital subtraction angiography (DSA), or tissue oxygen partial pressure (PtiO₂) increased by > 5 mmHg, or transcranial doppler (TCD) values decreased more than 30 cm/sec, or mean transit time (MTT) decreased below 6.5 secs in CT perfusion (CTP). Patient outcome was assessed at 6 months with the modified Rankin Scale (mRS).

Results

Seven patients were enrolled between February 2013 and September 2016. Median duration of iNO administration was 23 h. The primary endpoint was reached in all patients (five out of 17 DSA examinations, 19 out of 29 PtiO₂ time points, nine out of 26 TCD examinations, three out of five CTP examinations). No adverse events necessitating the cessation of iNO were observed. At 6 months, three patients presented with a mRS score of 0, one patient each with an mRS score of 2 and 3, and two patients had died.

Conclusion

Administration of iNO in SAH patients is safe. These results call for a larger prospective evaluation.

Early Fevers and Elevated Neutrophil-to-Lymphocyte Ratio are Associated with Repeat Endovascular Interventions for Cerebral Vasospasm in Patients with Aneurysmal Subarachnoid Hemorrhage

BACKGROUND

Patients with aneurysmal subarachnoid hemorrhage (aSAH) may develop refractory arterial cerebral vasospasm requiring multiple endovascular interventions. The aim of our study is to evaluate variables associated with need for repeat endovascular treatments in refractory vasospasm and to identify differences in outcomes following one versus multiple treatments.

METHODS

We retrospectively reviewed patients treated for aSAH between 2017 and 2020 at two tertiary care centers. We included patients who underwent treatment (intraarterial infusion of vasodilatory agents or mechanical angioplasty) for radiographically diagnosed vasospasm in our analysis. Patients were divided into those who underwent single treatment versus those who underwent multiple endovascular treatments for vasospasm.

RESULTS

Of the total 418 patients with aSAH, 151 (45.9%) underwent endovascular intervention for vasospasm. Of 151 patients, 95 (62.9%) underwent a single treatment and 56 (37.1%) underwent two or more treatments. Patients were more likely to undergo multiple endovascular treatments if they had a Hunt-Hess score > 2 (odds ratio [OR] 5.10 [95% confidence interval (CI) 1.82-15.84]; p = 0.003), a neutrophil-to-lymphocyte ratio > 8.0 (OR 3.19 [95% CI 1.40-7.62]; p = 0.028), and more than two fevers within the first 5 days of admission (OR 7.03 [95% CI 2.68-20.94]; p < 0.001). Patients with multiple treatments had poorer outcomes, including increased length of stay, delayed cerebral ischemia, in-hospital complications, and higher modified Rankin scores at discharge.

CONCLUSIONS

A Hunt-Hess score > 2, a neutrophil-to-lymphocyte ratio > 8.0, and early fevers may be predictive of need for multiple endovascular interventions in refractory cerebral vasospasm after aSAH. These patients have poorer functional outcomes at discharge and higher rates of in-hospital complications.

Anesthesia modality does not affect clinical outcomes of intra-arterial vasodilator treatment in patients with symptomatic cerebral vasospasms

Background: Delayed cerebral ischemia and cerebral vasospasm remain the leading causes of poor outcome in survivors of aneurysmal subarachnoid hemorrhage. Refractory cerebral vasospasms can be treated with endovascular vasodilator therapy, which can either be performed in conscious sedation or general anesthesia. The aim of this study is to compare the effect of the anesthesia modality on long-term clinical outcomes in patients undergoing endovascular vasodilator therapy due to cerebral vasospasm and hypoperfusion.

Methods: Modified Rankin Scale (mRS) scores were retrospectively analyzed at time of discharge from the hospital and six months after aneurysmal subarachnoid hemorrhage. Additionally, National Institutes of Health Stroke Scale (NIHSS) was assessed 24 hours before, immediately before, immediately after, and 24 hours after endovascular vasodilator therapy, and at discharge and six months. Interventional parameters such as duration of intervention, choice and dosage of vasodilator and number of arteries treated were also recorded.

Results: A total of 98 patients were included in this analysis and separated into patients who had interventions in conscious sedation, general anesthesia and a mix of both. Neither mRS at discharge nor at six months showed a significant difference for functionally independent outcomes (mRS 0-2) between groups. NIHSS before endovascular vasodilator therapy was significantly higher in patients receiving interventions in general anesthesia but did not differ anymore between groups six months after the initial bleed.

Conclusion: This study did not observe a difference in outcome whether patients underwent endovascular vasodilator therapy in general anesthesia or conscious sedation for refractory cerebral vasospasms. Hence, the choice should be made for each patient individually.

Intra-arterial nimodipine for severe cerebral vasospasm after aneurysmal subarachnoid haemorrhage - neurological and radiological outcome

Objectives

Cerebral vasospasm is a known complication to aneurysmal subarachnoid haemorrhage, which can lead to severe morbidity. Intra-arterial vasodilation therapy is widely used as a last resort treatment in patients with symptomatic refractory cerebral vasospasm but there is limited data about the outcome. The purpose of this study is to evaluate the neurological and radiological outcome in patients treated with intra-arterial nimodipine in relation to cerebral infarction, procedure-related complications and clinical outcome.

Methods

Patients with refractory cerebral vasospasm treated with intra-arterial nimodipine during 2009–2020 at Sahlgrenska University Hospital were retrospectively reviewed. Neurological outcome (modified Rankin Scale) at 30 days and 6 months, development of cerebral infarction after intra-arterial nimodipine treatment and procedure-related complications were studied.

Results

Forty-eight patients were treated with intra-arterial nimodipine. A good outcome (modified Rankin Scale 0–2) was seen in 25% (n = 12) of the patients after 30 days and in 47% (n = 22) of the patients after six months. Infarction related to the vasospastic vessel after treatment with intra-arterial nimodipine was seen in 60% (n = 29) of the patients. A total of 124 procedures with intra-arterial nimodipine were performed where complications were seen in 10 (21%) patients in 10 (8%) procedures. Four (8%) patients died within 30 days.

Conclusions

A majority of patients developed an ischaemic cerebral infarction in spite of intra-arterial nimodipine treatment. However, a good clinical recovery was seen in almost half of the patients after 6 months. Minor complications occurred in one out of five patients.

Levosimendan as a therapeutic strategy to prevent neuroinflammation after aneurysmal subarachnoid hemorrhage?

BACKGROUND

Poor patient outcomes after aneurysmal subarachnoid hemorrhage (SAH) occur due to a multifactorial process, mainly involving cerebral inflammation (CI), delayed cerebral vasospasm (DCVS), and delayed cerebral ischemia, followed by neurodegeneration. CI is mainly triggered by enhanced synthesis of serotonin (5-HT), prostaglandin F2alpha (PGF2a), and cytokines such as interleukins. Levosimendan (LV), a calcium-channel sensitizer, has already displayed anti-inflammatory effects in patients with severe heart failure. Therefore, we wanted to elucidate its potential anti-inflammatory role on the cerebral vasculature after SAH.

METHODS

Experimental SAH was induced by using an experimental double-hemorrhage model. Sprague Dawley rats were harvested on day 3 and day 5 after the ictus. The basilar artery was used for isometric investigations of the muscular media tone. Vessel segments were either preincubated with LV or without, with precontraction performed with 5-HT or PGF2a followed by application of acetylcholine (ACh) or LV.

RESULTS

After preincubation with LV 10^-4 M and 5-HT precontraction, ACh triggered a strong vasorelaxation in sham segments (LV 10^-4 M, E_max 65%; LV 10^-5 M, E_max 48%; no LV, E_max 53%). Interestingly, SAH D3 (LV 10^-4, E_max 76%) and D5 (LV 10^-4, E_max 79%) segments showed greater vasorelaxation compared with sham. An LV series after PGF2a precontraction showed significantly enhanced relaxation in the sham (P=0.004) and SAH groups (P=0.0008) compared with solvent control vessels.

CONCLUSIONS

LV application after SAH seems to beneficially influence DCVS by antagonizing 5-HT- and PGF2a-triggered vasoconstriction. Considering this spasmolytic effect, LV might have a role in the treatment of SAH, additionally in selected patients suffering takotsubo cardiomyopathy.

Vasospasm: Role of Imaging in Detection and Monitoring Treatment

Cerebral vasospasm (VS) and delayed cerebral ischemia (DCI) are important complications of aneurysmal subarachnoid hemorrhage (ASAH). Imaging approaches to VS monitoring include noninvasive bedside assessment with transcranial Doppler ultrasonography, angiographic evaluation with digital subtraction angiography, and computed tomography (CT) angiography. DCI is a clinical diagnosis and is not fully explained by the presence of angiographic VS. CT perfusion has shown clinical utility and implications for future research in the evaluation of DCI in patients with ASAH. This review article discusses the common approaches to diagnosis and monitoring of VS and DCI, current treatment strategies, and future research directions.

Reliability of the Diagnosis of Cerebral Vasospasm Using Catheter Cerebral Angiography: A Systematic Review and Inter- and Intraobserver Study

BACKGROUND AND PURPOSE

Conventional angiography is the benchmark examination to diagnose cerebral vasospasm, but there is limited evidence regarding its reliability. Our goals were the following: 1) to systematically review the literature on the reliability of the diagnosis of cerebral vasospasm using conventional angiography, and 2) to perform an agreement study among clinicians who perform endovascular treatment.

MATERIALS AND METHODS

Articles reporting a classification system on the degree of cerebral vasospasm on conventional angiography were systematically searched, and agreement studies were identified. We assembled a portfolio of 221 cases of patients with subarachnoid hemorrhage and asked 17 raters with different backgrounds (radiology, neurosurgery, or neurology) and experience (junior ≤10 and senior >10 years) to independently evaluate cerebral vasospasm in 7 vessel segments using a 3-point scale and to evaluate, for each case, whether findings would justify endovascular treatment. Nine raters took part in the intraobserver reliability study.

RESULTS

The systematic review showed a very heterogeneous literature, with 140 studies using 60 different nomenclatures and 21 different thresholds to define cerebral vasospasm, and 5 interobserver studies reporting a wide range of reliability (κ = 0.14-0.87). In our study, only senior raters reached substantial agreement (κ ≥ 0.6) on vasospasm of the supraclinoid ICA, M1, and basilar segments and only when assessments were dichotomized (presence or absence of ≥50% narrowing). Agreement on whether to proceed with endovascular management of vasospasm was only fair (κ ≤ 0.4).

CONCLUSIONS

Research on cerebral vasospasm would benefit from standardization of definitions and thresholds. Dichotomized decisions by experienced readers are required for the reliable angiographic diagnosis of cerebral vasospasm.

The Impact of Intra-Arterial Papaverine-Hydrochloride on Cerebral Metabolism and Oxygenation for Treatment of Delayed-Onset Post-Subarachnoid Hemorrhage Vasospasm

BACKGROUND

Delayed posthemorrhagic vasospasm remains among the major complications after aneurysmal subarachnoid hemorrhage (SAH) and can result in devastating ischemic strokes. As rescue therapy, neurointerventional procedures are used for selective vasodilatation.

OBJECTIVE

To investigate the effects of intra-arterial papaverine-hydrochloride on cerebral metabolism and oxygenation.

METHODS

A total of 10 consecutive patients, suffering from severe aneurysmal SAH were prospectively included. Patients were under continuous multimodality neuromonitoring and required intra-arterial papaverine-hydrochloride for vasospasm unresponsive to hypertensive therapy. Cerebral metabolism (microdialysis), brain tissue oxygen tension (ptiO2), intracranial pressure (ICP), and cerebral perfusion pressure (CPP) were analyzed for a period of 12 h following intervention.

RESULTS

A median dose of 125 mg papaverine-hydrochloride was administered ipsilateral to the multimodality probe. Angiographic improvement of cerebral vasospasm was observed in 80% of patients. During intervention, a significant elevation of ICP (13.7 ± 5.2 mmHg) and the lactate-pyruvate ratio (LPR) (54.2 ± 15.5) was observed, whereas a decrease in cerebral glucose (0.9 ± 0.5 mmol/L) occurred. Within an hour, an increase of cerebral lactate (5.0 ± 2.0 mmol/L) and glycerol (104.4 ± 89.8 μmol/L) as well as a decrease of glucose (0.9 ± 0.4 mmol/L) were measured. In 2 to 5 h after treatment, the LPR significantly decreased (pretreatment: 39.3 ± 15.3, to lowest 30.5 ± 6.7). Cerebral pyruvate levels increased in 1 to 10 h (pretreatment: 100.1 ± 33.1 μmol/L, to highest 141.4 ± 33.7 μmol/L) after intervention. No significant changes in ptiO2 or CPP occurred.

CONCLUSION

The initial detrimental effects of the endovascular procedure itself were outweighed by an improved cerebral metabolism within 10 h thereafter. As the effect was very limited, repeated interventions or continuous application should be considered.

The Role of Losartan as a Potential Neuroregenerative Pharmacological Agent after Aneurysmal Subarachnoid Haemorrhage

BACKGROUND

Cerebral vasospasm (CVS) remains a major cause of delayed cerebral ischaemia following aneurysmal subarachnoid haemorrhage (SAH), making it a life-threatening type of stroke with high morbidity and mortality. Endothelin-1 is known as key player mediating a strong vasocontractile effect. Interestingly, losartan restores the impaired vasorelaxative ET(B1) receptor function in a non-competitive direct fashion. With this study, we aimed to investigate a potential losartan-dependent vasodilatory effect vice versa by inhibiting NO release through L-NAME, thus pushing forward concepts to alleviate vasospasm and possibly prevent ischaemia and neurodegeneration.

METHODS

Cerebral vasospasm was induced by the use of an established double-injection rat model. Sprague-Dawley rats were culled on Day 3 after the ictus, and the vasospastic basilar artery was harvested for isometric investigations of the vessel tone. Ring segments were preincubated with and without L-NAME and/or losartan.

RESULTS

Preincubation with L-NAME induced dose-dependent vasoconstriction via endothelin-1 in the non-SAH cohort, which was dose-dependently reduced by losartan. After SAH and dose-dependent endothelin-1 administration, maximal contraction was achieved in the control group without losartan. Furthermore, this maximal contraction was significantly decreased in the losartan group and was reversed by L-NAME.

CONCLUSIONS

After SAH, losartan was shown to positively influence the ET(B1) receptor pathway in a non-competitive direct agonistic and indirect fashion. Losartan alleviated the maximum contraction triggered by endothelin-1. This effect was resolved due to NO inhibition by L-NAME. Considering this spasmolytic effect of losartan besides its already well-known effects (attenuating cerebral inflammation, restoring cerebral autoregulation and reducing epileptogenic activity) and alleviating early brain injury, losartan seems to have potential as a promising pharmacological agent after SAH.

The Role of Sartans in the Treatment of Stroke and Subarachnoid Hemorrhage: A Narrative Review of Preclinical and Clinical Studies

Background: Delayed cerebral vasospasm (DCVS) due to aneurysmal subarachnoid hemorrhage (aSAH) and its sequela, delayed cerebral ischemia (DCI), are associated with poor functional outcome. Endothelin-1 (ET-1) is known to play a major role in mediating cerebral vasoconstriction. Angiotensin-II-type-1-receptor antagonists such as Sartans may have a beneficial effect after aSAH by reducing DCVS due to crosstalk with the endothelin system. In this review, we discuss the role of Sartans in the treatment of stroke and their potential impact in aSAH. Methods: We conducted a literature research of the MEDLINE PubMed database in accordance with PRISMA criteria on articles published between 1980 to 2019 reviewing: "Sartans AND ischemic stroke". Of 227 studies, 64 preclinical and 19 clinical trials fulfilled the eligibility criteria. Results: There was a positive effect of Sartans on ischemic stroke in both preclinical and clinical settings (attenuating ischemic brain damage, reducing cerebral inflammation and infarct size, increasing cerebral blood flow). In addition, Sartans reduced DCVS after aSAH in animal models by diminishing the effect of ET-1 mediated vasoconstriction (including cerebral inflammation and cerebral epileptogenic activity reduction, cerebral blood flow autoregulation restoration as well as pressure-dependent cerebral vasoconstriction). Conclusion: Thus, Sartans might play a key role in the treatment of patients with aSAH.

Distal Balloon Angioplasty of Cerebral Vasospasm Decreases the Risk of Delayed Cerebral Infarction

BACKGROUND AND PURPOSE

Conventional angioplasty of cerebral vasospasm combines proximal balloon angioplasty (up to the first segment of cerebral arteries) with chemical angioplasty for distal arteries. Distal balloon angioplasty (up to the second segment of cerebral arteries) has been used in our center instead of chemical angioplasty since January 2015. We aimed to assess the effect of this new approach in patients with aneurysmal SAH.

MATERIALS AND METHODS

The occurrence, date, territory, and cause of any cerebral infarction were retrospectively determined and correlated to angioplasty procedures. Delayed cerebral infarction, new angioplasty in the territory of a previous angioplasty, angioplasty complications, 1-month mortality, and 6- to 12-month modified Rankin Scale ≤ 2 were compared between 2 periods (before-versus-after January 2015, from 2012 to 2017) with adjustment for age, sex, World Federation of Neurosurgical Societies score, and the modified Fisher grade.

RESULTS

Three-hundred-ninety-two patients were analyzed (160 before versus 232 after January 2015). Distal balloon angioplasty was associated with the following: higher rates of angioplasty (43% versus 27%, P < .001) and intravenous milrinone (31% versus 9%, P < .001); lower rates of postangioplasty delayed cerebral infarction (2.2% versus 7.5%, P = .01) and new angioplasty (8% versus 19%, P = .003) independent of the rate of patients treated by angioplasty and milrinone; and the same rates of stroke related to angioplasty (3.6% versus 3.1%, P = .78), delayed cerebral infarction (7.7% versus 12.5%, P = .12), mortality (10% versus 11%, P = .81), and favorable outcome (79% versus 73%, P = .21).

CONCLUSIONS

Our study suggests that distal balloon angioplasty is safe and decreases the risk of delayed cerebral infarction and the recurrence of vasospasm compared with conventional angioplasty. It fails to show a clinical benefit possibly because of confounding changes in adjuvant therapies of vasospasm during the study period.

Effect of intraoperative infusion of dexmedetomidine on postoperative recovery in patients undergoing endovascular interventional therapies: A prospective, randomized, controlled trial

BACKGROUND

Rapid emergence from general anesthesia during endovascular interventional therapies (EITs) is important. However, the solution that improved quality of both analepsia and postoperative recovery after EITs has not been specifically addressed. We conducted this prospective, randomized, controlled trial to evaluate the intraoperative infusion of dexmedetomidine on quality of analepsia and postoperative recovery in patients undergoing EITs.

METHODS

Eighty-six patients undergoing EITs were divided into three groups: RD1 (dexmedetomidine at an initial dose of 0.5 μg/kg for 10 min adjusted to 0.2 μg kg^-1  hr^-1 throughout EIT), RD2 (dexmedetomidine at an initial dose of 0.5 μg/kg for 10 min adjusted to 0.4 μg kg^-1  hr^-1 throughout EIT), and RD3 (dexmedetomidine at an initial dose of 0.5 μg/kg for 10 min adjusted to 0.6 μg kg^-1  hr^-1 throughout EIT). An analgesia system delivered sufentanil only. The primary outcome measure was the total consumption of nimodipine during the first 48 hr after surgery. The secondary outcome measures were sufentanil consumption, pain intensity, hemodynamics, functional activity score (FAS), neurologic examination, level of sedation (LOS), and Bruggrmann comfort scale (BCS). We also recorded the intraoperative hemodynamic data, requirement of narcotic and vasoactive drugs, prevalence of complications and symptomatic cerebral vasospasm, duration of postanesthesia care unit (PACU) stay, Glasgow Outcome Score (GOS) at 3 months, and prevalence of cerebral infarction 30 days after surgery.

RESULTS

Dexmedetomidine application in the regimen RD3 reduced the consumption of the total dose of nimodipine and sufentanil 48 hr after surgery, prevalence of symptomatic cerebral vasospasm, consumption of narcotic drugs and nimodipine during surgery, pain intensity during the first 8 hr after surgery, and increased both BCS during the first 4 hr after surgery and hemodynamic stability. However, the LOS was increased at the 0.5 hr after surgery and surgeon satisfaction score was lower. There were no significant differences among the groups for consumption of vasoactive drugs except urapidil, Glasgow coma scale (GCS) and FAS during the first 48 hr after surgery, GOS at 3 months, and cerebral infarction after 30 days.

CONCLUSIONS

Dexmedetomidine (an initial dose of 0.5 μg/kg for 10 min adjusted to 0.6 μg kg^-1 hr^-1 throughout EIT) could reduce the total consumption of nimodipine and opioid during the first 48 hr after surgery, the concerning adverse effects, and improve pain scores. The optimal dosage of dexmedetomidine during EITs merits further investigation.

A Review of the Management of Cerebral Vasospasm After Aneurysmal Subarachnoid Hemorrhage

BACKGROUND

Despite decades of research, cerebral vasospasm (CV) continues to account for high morbidity and mortality in patients who survive their initial aneurysmal subarachnoid hemorrhage.

OBJECTIVE

To define the scope of the problem and review key treatment strategies that have shaped the way CV is managed in the contemporary era.

METHODS

A literature search was performed of CV management after aneurysmal subarachnoid hemorrhage.

RESULTS

Recent advances in neuroimaging have led to improved detection of vasospasm, but established treatment guidelines including hemodynamic augmentation and interventional procedures remain highly variable among neurosurgical centers. Experimental research in subarachnoid hemorrhage continues to identify novel targets for therapy.

CONCLUSIONS

Proactive and preventive strategies such as oral nimodipine and endovascular rescue therapies can reduce the morbidity and mortality associated with CV.

Endovascular Rescue Treatment for Delayed Cerebral Ischemia After Subarachnoid Hemorrhage Is Safe and Effective

Background: The implementation of rescue efforts for delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage remains largely empirical for a lack of supporting evidence, while the associated risk profile is also unclear. Objective: The present study evaluates the safety and efficacy of endovascular rescue treatment (ERT, continuous intraarterial nimodipine; IAN, transcutaneous balloon angioplasty, TBA). Methods: In this prospective observational study, we assessed periprocedural complications and side effects in context of ERT. We evaluated neurological status, multimodal neuromonitoring (p_tiO₂, lactate/pyruvate ratio, transcranial doppler), and cranial imaging (CTP, DSA). All parameters were included into multivariate analysis to determine predictors for the need of retreatment. Results: We included 33 consecutive patients with 54 ERT (IAN n = 35; TBA n = 13; TBA + IAN n = 6). We recorded no serious complications and initial improvement in all parameters (neurostatus 72.3% of patients; p_tiO₂ 15.0 ± 11.7 to 25.8 ± 15.5 mmHg, p < 0.0001; lactate/pyruvate ratio 46.3 ± 27.5 to 31.0 ± 9.7, p <0.05; transcranial doppler 139.0 ± 46.3 to 98.9 ± 29.6 cm/s, p < 0.05; CTP 81.6% of patients; DSA 93.1% of patients). Retreatment (n = 16, 48.5%) was independently associated with preinterventional p_tiO₂ < 5 mmHg (p <0.01) and early (<72 h) discontinuation of IAN treatment (p = 0.08). DCI related cerebral infarction was noted in n = 8 patients (24.2%). At 3 months after discharge, favorable outcome was noted for n = 11 (35.5%) patients. Conclusion: Provided a detailed decision tree, timely ERT can provide a relatively safe and effective treatment option in those highly-selected patients undergoing multimodality monitoring where conservative treatment options are exhausted. Continuous treatment in particular may be suitable to surpass sustained DCI and was associated with a low rate of DCI related infarction and comparably high percentage of good outcome.