Update on endovascular therapies for cerebral vasospasm induced by aneurysmal subarachnoid hemorrhage

Papaverine attenuates the progression of alpha naphthylisothiocyanate induce cholestasis in rats

Cholestasis is a hepatobiliary condition that manifests as acute or chronic and results from disruptions in the bile flow, formation, or secretion processes. The Farnesoid X receptor (FXR) is a vital target for the therapy of cholestasis since it regulates BA homeostasis. Despite the discovery of multiple active FXR agonists, there are still no effective treatments for cholestasis. Papaverine is identified as an FXR agonist.This study investigates papaverine's efficacy and probable mechanism in protecting against alpha naphthylisothiocyanate (ANIT) induced cholestasis. Thirty male albino rats were divided into three groups, each with ten rats. Group I (control) rats were administered 1 mL/kg corn oil 48 h before sacrifice; group II rats were orally administered 100 mg/kg ANIT. Group III received a 200 mg/kg dosage of papaverine over seven consecutive days. A single dose of ANIT at a concentration of 100 mg/kg was orally administered on the fifth day; group II and III animals were euthanized 48 h after inducing cholestasis, and serum concentrations of liver function tests and total bile acid (TBA) were measured. Besides measuring the inflammatory mediator's tumor necrosis factor-alpha (TNF-α) and interleukin 1 (IL-1β), antioxidant markers such as superoxide dismutase (SOD) and glutathione (GSH) were also assessed. The findings indicated the enhancement in the liver function test and total bile acids, as well as in liver histology; papaverine significantly lowered TNF-α and IL-1β while SOD and GSH significantly increased. Additionally, papaverine upregulates Fxr gene expression, bile salt export pump (Besp), small heterodimer partner (shp), hepatocyte nuclear factor 1α (Hnfα), nuclear factor erythroid 2-related factor (Nrf2), heme oxygenase (Ho-1), NAD(P)H quinone oxidoreductase 1 (Nqo1). Furthermore, papaverine increased protein expressions of Sirtuin1. (SIRT 1), FXR, HO-1, and BSEP levels in the rats' livers. The protective effects of papaverine may be attributed to the activation of FXR signaling pathways. These findings revealed that papaverine protects against ANIT-induced Cholestasis.

Papaverine: A Miraculous Alkaloid from Opium and Its Multimedicinal Application

The pharmacological actions of benzylisoquinoline alkaloids are quite substantial, and have recently attracted much attention. One of the principle benzylisoquinoline alkaloids has been found in the unripe seed capsules of Papaver somniferum L. Although it lacks analgesic effects and is unrelated to the compounds in the morphine class, it is a peripheral vasodilator and has a direct effect on vessels. It is reported to inhibit the cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) phosphodiesterase in smooth muscles, and it has been observed to increase intracellular levels of cAMP and cGMP. It induces coronary, cerebral, and pulmonary artery dilatation and helps to lower cerebral vascular resistance and enhance cerebral blood flow. Current pharmacological research has revealed that papaverine demonstrates a variety of biological activities, including activity against erectile dysfunction, postoperative vasospasms, and pulmonary vasoconstriction, as well as antiviral, cardioprotective, anti-inflammatory, anticancer, neuroprotective, and gestational actions. It was recently demonstrated that papaverine has the potential to control SARS-CoV-2 by preventing its cytopathic effect. These experiments were carried out both in vitro and in vivo and require an extensive understanding of the mechanisms of action. With its multiple mechanisms, papaverine can be considered as a natural compound that is used to develop therapeutic drugs. To validate its applications, additional research is required into its precise therapeutic mechanisms as well as its acute and chronic toxicities. Therefore, the goal of this review is to discuss the major studies and reported clinical studies looking into the pharmacological effects of papaverine and the mechanisms of action underneath these effects. Additionally, it is recommended to conduct further research via significant pharmacodynamic and pharmacokinetic studies.

Emerging therapeutics agents and recent advances in drug repurposing for Alzheimer's disease

Alzheimer's disease (AD) is a multivariate and diversified disease and affects the most sensitive areas of the brain, the cerebral cortex, and the hippocampus. AD is a progressive age-related neurodegenerative disease most often associated with memory deficits and cognition that get more worsen over time. The central theory on the pathophysiological hallmark features of AD is characterized by the accumulation of amyloid β (Aβ) peptides, also associated with tau proteins (τ) dysfunctioning which leads to distorted microtubular structure, affects the cholinergic system, and mitochondrial biogenesis. This review emphasizes how simple it is to find novel treatments for AD and focuses on several recently developed medications through repurposing that can speed up traditional drug development.

ABO blood group in aneurysmal subarachnoid haemorrhage-a pilot study

PURPOSE

To evaluate the distribution and impact of ABO blood group on the baseline characteristics and clinical outcomes of patients presenting with aneurysmal subarachnoid haemorrhage (aSAH).

METHODS

Retrospective, single-centre study of patients admitted to a neurosurgical department in the UK, with a diagnosis of spontaneous subarachnoid haemorrhage between May 2014 and January 2020. Patients were categorised by ABO blood type and by Rhesus status. Clinical outcomes such as initial bleeding, rebleeding, delayed cerebral ischaemia (DIND) and venous thromboembolism were analysed in relation to the size of their association with ABO blood type. Hospital mortality rate, Glasgow Outcome Score (GOS) - at discharge and 3 months post-ictus, requirement for ventriculoperitoneal shunt insertion, discharge destination and inpatient length of stay were also considered.

RESULTS

Four-hundred twelve adult patients admitted with aSAH were included in our analysis. The distribution of ABO group or Rhesus status in our cohort did not differ significantly from the general population in the UK. Blood group A patients had a significantly increased risk of developing DIND, compared with non-blood group A patients (OR, 1.88 [95% CI: 1.10-3.21]).

CONCLUSIONS

ABO blood type appears to influence aSAH sequelae. Blood group A patients are at highest risk of DIND following aSAH.

Novel Papaverine Metal Complexes with Potential Anticancer Activities

Cancer is one of the leading causes of death worldwide. Although several potential therapeutic agents have been developed to efficiently treat cancer, some side effects can occur simultaneously. Papaverine, a non-narcotic opium alkaloid, is a potential anticancer drug that showed selective antitumor activity in various tumor cells. Recent studies have demonstrated that metal complexes improve the biological activity of the parent bioactive ligands. Based on those facts, herein we describe the synthesis of novel papaverine–vanadium(III), ruthenium(III) and gold(III) metal complexes aiming at enhancing the biological activity of papaverine drug. The structures of the synthesized complexes were characterized by various spectroscopic methods (IR, UV–Vis, NMR, TGA, XRD, SEM). The anticancer activity of synthesized metal complexes was evaluated in vitro against two types of cancer cell lines: human breast cancer MCF-7 cells and hepatocellular carcinoma HepG-2 cells. The results revealed that papaverine-Au(III) complex, among the synthesized complexes, possess potential antimicrobial and anticancer activities. Interestingly, the anticancer activity of papaverine–Au(III) complex against the examined cancer cell lines was higher than that of the papaverine alone, which indicates that Au-metal complexation improved the anticancer activity of the parent drug. Additionally, the Au complex showed anticancer activity against the breast cancer MCF-7 cells better than that of cisplatin. The biocompatibility experiments showed that Au complex is less toxic than the papaverine drug alone with IC₅₀ ≈ 111µg/mL. These results indicate that papaverine–Au(III) complex is a promising anticancer complex-drug which would make it a suitable candidate for further in vivo investigations.

Fasudil inhibits the activation of microglia and astrocytes of transgenic Alzheimer's disease mice via the downregulation of TLR4/Myd88/NF-κB pathway

Emerging evidence suggests an association of Alzheimer's Disease (AD) with microglial and astrocytic dysregulation. Recent studies have proposed that activated microglia can transform astrocytes to a neurotoxic A1 phenotype, which has been shown to be involved in the promotion of neuronal damage in several neurodegenerative diseases, including AD. In the present study, we observed an obvious microglial activation and A1-specific astrocyte response in the brain tissue of APP/PS1 Tg mice. Fasudil treatment improved the cognitive deficits of APP/PS1 Tg mice, inhibited microglial activation and promoted their transformation to an anti-inflammatory phenotype, and further shifted astrocytes from an A1 to an A2 phenotype. Our experiments suggest Fasudil exerted these functions by inhibing the expression of TLR4, MyD88, and NF-κB, which are key mediators of inflammation. Using in vitro experiments, we further validated in vivo findings. Our cell experiments indicated that Fasudil induces a shift of inflammatory microglia towards an anti-inflammatory phenotype. LPS-induced microglia-conditioned medium promotes A1 astrocytic polarization, but Fasudil treatment resulted in a direct transformation of A1 astrocytes to A2. To summarize, our results show that Fasudil inhibits the neurotoxic activation of microglia and shifts astrocytes towards a neuroprotective A2 phenotype, representing a promising candidate for AD treatment.

Anticancer effects of a non-narcotic opium alkaloid medicine, papaverine, in human glioblastoma cells

The interaction between high-mobility group box 1 protein (HMGB1) and receptor for advanced glycation end products (RAGE) is important for tumor cell growth. We investigated the tumor biological effects of HMGB1 and RAGE interaction. Previously, we identified an inhibitor of HMGB1/RAGE interaction, papaverine (a non-narcotic opium alkaloid), using a unique drug design system and drug repositioning approach. In the present study, we examined the anticancer effects of papaverine in human glioblastoma (GBM) temozolomide (TMZ; as a first-line anticancer medicine)-sensitive U87MG and TMZ-resistant T98G cells. HMGB1 supplementation in the culture medium promoted tumor cell growth in T98G cells, and this effect was canceled by papaverine. In addition, papaverine in T98G cells suppressed cancer cell migration. As an HMGB1/RAGE inhibitor, papaverine also significantly inhibited cell proliferation in U87MG and T98G cells. The effects of papaverine were evaluated in vivo in a U87MG xenograft mouse model by determining tumor growth delay. The results indicate that papaverine, a smooth muscle relaxant, is a potential anticancer drug that may be useful in GBM chemotherapy.

Influence of ABO blood type on the outcome after non-aneurysmal subarachnoid hemorrhage

BACKGROUND

In patients with non-aneurysmal subarachnoid hemorrhage (NA-SAH), the etiology is unknown and the bleeding source remains unidentified. However, the ABO blood type system has a profound role in patient's hemostasis and thrombosis. To date, the aspect of ABO blood type in incidence, clinical course, and outcome after NA-SAH has not been investigated.

METHODS

In this retrospective analysis, 81 patients with non-traumatic and non-aneurysmal subarachnoid hemorrhage treated between 2010 and 2014 at the author's institution were included. WFNS admission status, cerebral vasospasm, delayed infarction, ventriculoperitoneal shunt necessity, the Fisher grade, and the modified Rankin Scale were analyzed for their association with ABO blood type. Four hundred seventy patients with aneurysmal subarachnoid hemorrhage served as a control group.

RESULTS

The AB blood type is more frequent in NA-SAH compared to aneurysmal patients and the German population (OR 2.45, p ≤ 0.05). Furthermore, NA-SAH with AB blood type showed a similar sequelae compared to aneurysmal patients in terms of shunt necessity (OR 2.00, p ≥ 0.05), cerebral vasospasm (OR 1.66, p ≥ 0.05), and delayed infarctions (OR 1.07, p ≥ 0.05).

CONCLUSION

The clinical course of NA-SAH AB blood type patients shows similar severity as of aneurysmal subarachnoid hemorrhage. Therefore, patients with AB blood type should be under intensified observation.

Effect of intrathecal milrinone injection via lumbar catheter on delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage

OBJECTIVE

Delayed cerebral ischemia (DCI) is an important complication after aneurysmal subarachnoid hemorrhage (aSAH). Although intrathecal milrinone injection via lumbar catheter to prevent DCI has been previously reported to be safe and feasible, its effectiveness remains unknown. The goal of this study was to evaluate whether intrathecal milrinone injection treatment after aSAH significantly reduced the incidence of DCI.

METHODS

The prospectively maintained aSAH database was used to identify patients treated between January 2010 and December 2015. The cohort included 274 patients, with group assignment based on treatment with intrathecal milrinone injection or not. A propensity score model was generated for each patient group, incorporating relevant patient variables.

RESULTS

After propensity score matching, 99 patients treated with intrathecal milrinone injection and 99 without treatment were matched on the basis of similarities in their demographic and clinical characteristics. There were significantly fewer DCI events (4% vs 14%, p = 0.024) in patients treated with intrathecal milrinone injection compared with those treated without it. However, there were no significant differences between the 2 groups with respect to their 90-day functional outcomes (46% vs 36%, p = 0.31). The likelihood of chronic secondary hydrocephalus, meningitis, and congestive heart failure as complications of intrathecal milrinone injection therapy was also similar between the groups.

CONCLUSIONS

In propensity score–matched groups, the intrathecal administration of milrinone via lumbar catheter showed significant reduction of DCI following aSAH, without an associated increase in complications.

[Intra-arterial administration of verapamil for prevention and treatment of cerebral angiospasm after SAH due to cerebral aneurysm rupture]

AIM

The study purpose was to analyze the efficacy of intra-arterial administration of verapamil (IAV) in the treatment of angiospasm in SAH patients and to determine optimal parameters of the procedure. A number of studies demonstrated the efficacy of intra-arterial administration of vasodilators, in particular verapamil, in the treatment of angiospasm after aneurysmal SAH, which served the basis for inclusion of this method in the recommended protocol for treatment of SAH patients [1-7].

MATERIAL AND METHODS

We analyzed the efficacy of IAV in 35 patients in the acute period of SAH, with 77.2% of the patients having a Hunt-Hess score of III-V. The inclusion criteria were as follows: IAV within two weeks after SAH; excluded aneurysm; verapamil dose per administration of at least 15 mg; follow-up for at least three months. Efficacy endpoints were as follows: changes in spasm according to angiography and transcranial dopplerography (TCDG); development of ischemic lesions; clinical outcome according to the modified Rankin scale.

RESULTS

A total of 76 IAV procedures were performed. The verapamil dose per procedure was 36.7±9.7 mg, on average; the number of procedures varied from 1 to 5. One arterial territory was treated in 12 cases, two arterial territories were treated in 48 cases, and three arterial territories were treated in 15 cases. Typical adverse reactions included decreased blood pressure, a reduced heart rate, and elevated ICP. In all cases, TCDG revealed signs of reduced angiospasm - a 20-40% decrease in the LBFV in the M1 MCA. Four (11.4%) patients died; of these, only one died due to angiospasm progression. On examination at 3 months or more after discharge, favorable outcomes were observed in 74.3% of cases.

CONCLUSION

IAV is associated with a low risk of significant complications. IAV should be performed under control of systemic hemodynamics and ICP. The indications for IAV include signs of moderate worsening or severe angiospasm according to TCDG and/or angiography. The IAV procedure may be performed every day. Further clarification of the IAV procedure and evaluation of clinical outcomes under prospective study conditions are required.

Endovascular Treatment of Symptomatic Vasospasm after Aneurysmal Subarachnoid Hemorrhage: A Three-year Experience

Objective

The cause of severe clinical vasospasm after aneurysmal subarachnoid hemorrhage remains unknown, despite extensive research over the past 30 years. However, the intra-arterial administration of vasodilating agents and balloon angioplasty have been successfully used in severe refractory cerebral vasospasm.

Materials and Methods

We retrospectively analyzed the data of 233 patients admitted to our institute with aneurysmal subarachnoid hemorrhage (SAH) over the past 3 years.

Results

Of these, 27 (10.6%) developed severe symptomatic vasospasm, requiring endovascular therapy. Vasospasm occurred at an average of 5.3 days after SAH. A total of 46 endovascular procedures were performed in 27 patients. Endovascular therapy was performed once in 18 (66.7%) patients, 2 times in 4 (14.8%) patients, 3 or more times in 5 (18.5%) patients. Intra-arterial vasodilating agents were used in 44 procedures (27 with nimodipine infusion, 17 with nicardipine infusion). Balloon angioplasty was performed in only 2 (7.4%) patients. The Average nimodipine infusion volume was 2.47 mg, and nicardipine was 3.78 mg. Most patients recovered after the initial emergency room visit. Two patients (7.4%) worsened, but there were no deaths.

Conclusion

With advances in endovascular techniques, administration of vasodilating agents and balloon angioplasty reduces the morbidity and mortality of vasospasm after aneurysmal SAH.

Inhibition of Rho-kinase by Fasudil protects dopamine neurons and attenuates inflammatory response in an intranasal lipopolysaccharide-mediated Parkinson's model

Microglia activation and inflammatory factors in brain microenvironment are associated with degeneration of neurons in the substantia nigra (SN) of Parkinson's disease (PD) patients and various PD models. There is increasing evidence that the Rho/ROCK (Rho kinase) signalling pathway may play a critical role in the inflammatory response, and ROCK inhibitor has been reported to have neuroprotective effects. In this study, we examined the neuroprotective potential and possible mechanism of ROCK inhibitor Fasudil in an intranasal lipopolysaccharide (LPS)-induced PD model. ROCK was activated with LPS stimulation and inhibited by Fasudil treatment in this PD model. Behavioural tests demonstrated a clear improvement in motor performance after Fasudil treatment. Furthermore, Fasudil resulted in a significant attenuation of dopamine cell loss, α-synuclein accumulation and inflammatory response with the reversion of inflammatory M1 to anti-inflammatory M2 microglia, decreased NF-кB activation, and IL-12 and TNF-α generation in the SN and olfactory bulb in this model. This study establishes a role for Fasudil in protecting against LPS-mediated dopamine degeneration and provides a therapeutic strategy for the treatment of PD.

Clinical Presentation, Imaging, and Management of Complications due to Neurointerventional Procedures

Neurointervention is a rapidly evolving and complex field practiced by clinicians with backgrounds ranging from neurosurgery to radiology, neurology, cardiology, and vascular surgery. New devices, techniques, and clinical applications create exciting opportunities for impacting patient care, but also carry the potential for new iatrogenic injuries. Every step of every neurointerventional procedure carries risk, and a thorough appreciation of potential complications is fundamental to maximizing safety. This article presents the most frequent and dangerous iatrogenic injuries, their presentation, identification, prevention, and management.

Current options for the management of aneurysmal subarachnoid hemorrhage-induced cerebral vasospasm: a comprehensive review of the literature

OBJECTIVES

Cerebral vasospasm is one of the leading causes of morbi-mortality following aneurysmal subarachnoid hemorrhage. The aim of this article is to discuss the current status of vasospasm therapy with emphasis on endovascular treatment.

METHODS

A comprehensive review of the literature obtained by a PubMed search. The most relevant articles related to medical, endovascular and alternative therapies were selected for discussion.

RESULTS

Current accepted medical options include the oral nimodipine and 'triple-H' therapy (hypertension, hypervolemia and hemodilution). Nimodipine remains the only modality proven to reduce the incidence of infarction. Although widely used, 'triple-H' therapy has not been demonstrated to significantly change overall outcome after cerebral vasospasm. Indeed, both induced hypervolemia and hemodilution may have deleterious effects, and more recent physiologic data favor normovolemia with induced hypertension or optimization of cardiac output. Endovascular options include percutaneous transluminal balloon angioplasty (PTA) and intra-arterial (IA) infusion of vasodilators. Multiple case reports and case series have been encountered in the literature using different drug regimens with diverse mechanisms of action. Compared with PTA, IA drug infusion has the advantages of distal penetration and a better safety profile. Its main disadvantages are the more frequent need for repeat treatments and its systemic hemodynamic repercussions. Alternative options using intraventricular/cisternal drug therapy and flow augmentation strategies have also shown possible benefits; however, their use is not yet as well established.

CONCLUSION

Blood pressure or cardiac output optimization should be the mainstay of hyperdynamic therapy. Endovascular treatment appears to have a positive impact on neurological outcome compared with the natural history of the disease. The role of intraventricular therapy and flow augmentation strategies in association with medical and endovascular treatment may, in the future, play a growing role in the management of patients with severe refractory vasospasm.

Rho kinase inhibitor fasudil protects against β-amyloid-induced hippocampal neurodegeneration in rats

BACKGROUND AND PURPOSE

Alzheimer's disease (AD) is a progressive neurodegenerative disorder, and Aβ-induced neuronal damage is the major pathology of AD. There is increasing evidence that neuroinflammation induced by Aβ is also involved in the pathogenesis of AD. Fasudil is a Rho kinase inhibitor and has been reported to have neuroprotective effects. In this study, the main purpose is to investigate whether fasudil has beneficial effects on cognitive impairment and neuronal toxicity induced by Aβ.

METHODS AND RESULTS

In the present study, intracerebroventricular injection of Aβ1-42 to rats resulted in marked cognitive impairment, severe neuronal damage, as well as increased IL-1β, tumor necrosis factor alpha (TNF-α) production, and NF-κB activation. Administration of fasudil significantly ameliorated the spatial learning and memory impairment, attenuated neuronal loss, and neuronal injury induced by Aβ1-42 . In addition, fasudil inhibited IL-1β and TNF-α production and NF-κB activation in the rat brain.

CONCLUSIONS

Fasudil can protect against Aβ-induced hippocampal neurodegeneration by suppressing inflammatory response, suggesting that fasudil might be a promising agent for the prevention and treatment of inflammation-related diseases, such as AD.

Relevance of animal models of subarachnoid hemorrhage for examining neurobehavioral changes

BACKGROUND AND PURPOSE

For many years survival and neurological functionality of patients were the main outcome measures after treatment of intracranial aneurysms. But, the variable outcomes of patients operated on in a delayed fashion or before the aneurysm rupture indicate that more precise measures are needed for assessment of not only the neurological but also the neuropsychological outcome. However, development and testing of such new tools requires better understanding of pathomechanisms of neurobehavioral changes evoked by aneurysmal subarachnoid hemorrhage (aSAH), which can be achieved using animal models.

METHODS

We reviewed and selected (1) animal models developed to investigate delayed cerebral vasospasm that could be useful for examining effects of brain injury evoked by aSAH and (2) a battery of neurobehavioral animal testing that can be used for assessment of patients after aSAH.

RESULTS

For every species used as an aSAH model, a battery of neurobehavioral test exists.

CONCLUSION

Albeit some limitations must be recognized, research using animal models of SAH should continue to play a critical role in assessment of cognitive and behavioral functions after aSAH.

NADPH oxidases as therapeutic targets in ischemic stroke

Reactive oxygen species (ROS) act physiologically as signaling molecules. In pathological conditions, such as ischemic stroke, ROS are released in excessive amounts and upon reperfusion exceed the body's antioxidant detoxifying capacity. This process leads to brain tissue damage during reoxygenation. Consequently, antioxidant strategies have long been suggested as a therapy for experimental stroke, but clinical trials have not yet been able to promote the translation of this concept into patient treatment regimens. As an evolution of this concept, recent studies have targeted the sources of ROS generation-rather than ROS themselves. In this context, NADPH oxidases have been identified as important generators of ROS in the cerebral vasculature under both physiological conditions in general and during ischemia/reoxygenation in particular. Inhibition of NADPH oxidases or genetic deletion of certain NADPH oxidase isoforms has been found to considerably reduce ischemic injury in experimental stroke. This review focuses on recent advances in the understanding of NADPH oxidase-mediated tissue injury in the cerebral vasculature, particularly at the level of the blood-brain barrier, and highlights promising inhibitory strategies that target the NADPH oxidases.

Safety of early endovascular catheterization and intervention through extracranial-intracranial bypass grafts

Object

The goal of this study was to demonstrate feasibility and evaluate technical aspects of early endovascular access through extracranial-intracranial (EC-IC) bypass grafts.

Methods

Patients undergoing endovascular interventions through the graft in the acute postoperative period following EC-IC bypass are presented. Results, complications, and technical nuances are reviewed.

Results

Fourteen endovascular procedures were performed in 5 patients after EC-IC bypass for ruptured aneurysms in 4 patients and posterior circulation ischemia in 1 patient. In 2 patients, a saphenous vein graft (SVG) was used to bypass the common carotid artery (CCA) to the middle cerebral artery (MCA). One patient underwent a superficial temporal artery (STA)–MCA bypass, and in 2 other patients the STA stump was connected to the intracranial circulation via an interposition SVG. The interval from surgery to endovascular intervention spanned 2–18 days; the indication was intracranial vasospasm in all patients. One case involved angioplasty of the proximal anastomosis on postoperative Day 14. All other interventions entailed proximal access through the bypass conduit for intraarterial infusion of vasodilators. Significant vasospasm of the STA itself was encountered in 2 patients during endovascular manipulation, and it was treated with intraarterial nitroglycerin. There were no cases of anastomotic disruption.

Conclusions

Endovascular catheterization and intervention involving a recent EC-IC bypass is feasible. The main limitation in this series was catheter-induced vasospasm involving the STA. A vein graft may be the more appropriate option in patients with subarachnoid hemorrhage who may require subsequent endovascular intervention for vasospasm.

Late cerebral ischaemia after subarachnoid haemorrhage: is cerebrovascular receptor upregulation the mechanism behind?

Late cerebral ischaemia after subarachnoid haemorrhage (SAH) carries high morbidity and mortality because of reduced cerebral blood flow (CBF) and subsequent cerebral ischaemia. This is associated with upregulation of contractile receptors in cerebral artery smooth muscles via the activation of intracellular signalling. In addition, delayed cerebral ischaemia after SAH is associated with inflammation and disruption of the blood-brain barrier (BBB). This article reviews recent evidence concerning the roles of vasoconstrictor receptor upregulation, inflammation and BBB breakdown in delayed cerebral ischaemia after SAH. In addition, recent studies investigating the role of various intracellular signalling pathways in these processes and the possibilities of targeting signalling components in SAH treatment are discussed. Studies using a rat SAH model have demonstrated that cerebral arteries increase their sensitivity to endogenous agonists such as ET-1 and 5-HT by increasing their smooth muscle expression of receptors for these after SAH. This is associated with reduced CBF and neurological deficits. A number of signal transduction components mediating this receptor upregulation have been identified, including the MEK-ERK1/2 pathway. Inhibition of MEK-ERK1/2 signalling has been shown to prevent cerebrovascular receptor upregulation and normalize CBF and neurological function after SAH in rats. At the same time, in rat SAH, certain cytokines and BBB-regulating proteins are upregulated in cerebral artery smooth muscles and treatment with MEK-ERK1/2 inhibitors prevents the induction of these proteins. Thus, inhibitors of MEK-ERK1/2 signalling exert multimodal beneficial effects in SAH.

Fasudil and ozagrel in combination show neuroprotective effects on cerebral infarction after murine middle cerebral artery occlusion

Rho kinase (ROCK), one of the serine/threonine kinases, is involved in pathologic conditions, and its activation causes neuronal cell death. Fasudil, a selective ROCK inhibitor, has been reported to cause increased cerebral blood flow (CBF) in the ischemic brain and protect against neuronal cell death by inhibiting ROCK. Ozagrel, a thromboxane A(2) synthase inhibitor, inhibits platelet aggregation and causes vasodilatation, thereby increasing CBF in cerebral thrombosis. The present study evaluates the combination therapy of fasudil and ozagrel on focal brain ischemia induced by middle cerebral artery occlusion (MCAO) in mice. Each monotherapy of fasudil at 10 mg/kg i.p. and ozagrel at 30 mg/kg i.p. significantly reduced cerebral infarction. The combination therapy of fasudil (3 mg/kg i.p.) and ozagrel (10 mg/kg i.p.), which are noneffective doses, resulted in reduction of cerebral infarction, and the protective effect was observed up to 5 min, but not 3 h, after reperfusion. Regional CBF after MCAO and phosphorylation of endothelial nitric-oxide synthase (NOS) significantly increased in response to the combination therapy, whereas these effects were not observed with monotherapy of either drug. The protective effect of combination treatment was antagonized by the treatment of a NOS inhibitor, nitro-l-arginine methyl ester hydrochloride. These findings indicate that the combination treatment of fasudil and ozagrel exhibits additive effects for neuroprotection after MCAO. These findings indicate that the combination treatment of fasudil and ozagrel may be useful as a potential therapeutic strategy for the treatment of stroke.

Intra-arterial nimodipine infusion for cerebral vasospasm in patients with aneurysmal subarachnoid hemorrhage

This study evaluated the efficacy of intra-arterial nimodipine infusion for symptomatic vasospasm in patients with aneurysmal subarachnoid hemorrhage (aSAH). Clinical data collected from 42 consecutive patients with symptomatic vasospasm after aSAH were retrospectively reviewed. Forty-two patients underwent 101 sessions of intra-arterial nimodipine infusion. Angiographic response, immediate clinical response, and clinical outcome were evaluated at discharge and six months later. Angiographic improvement was achieved in 82.2% of patients. The immediate clinical improvement rate was 68.3%, while the deterioration rate was 5.0%. A favorable clinical outcome was achieved in 76.2% at discharge and 84.6% six months. Vasospasm-related infarction occurred in 21.4%. There was no drug-related complication. The nimodipine group showed satisfactory outcomes. Nimodipine can be recommended as an effective and safe intra-arterial agent for the treatment of symptomatic vasospasm after aSAH.

Safety and efficacy of transluminal balloon angioplasty using a compliant balloon for severe cerebral vasospasm after an aneurysmal subarachnoid hemorrhage

OBJECTIVE

Vasospasm of cerebral vessels remains a major source of morbidity and mortality after an aneurysmal subarachnoid hemorrhage (SAH). The purpose of this study was to evaluate the safety and efficacy of transluminal balloon angioplasty (TBA) for SAH-induced vasospasm.

METHODS

Eleven patients with an angiographically confirmed significant vasospasm (>50% vessel narrowing and clinical deterioration) were studied. A total of 54 vessel segments with significant vasospasm were treated by TBA. Digital subtraction angiography was used to confirm the presence of vasospasm, and TBA was performed to dilate vasospastic arteries. Medical and angiographic reports were reviewed to determine technical efficacy and for procedural complications.

RESULTS

TBA using Hyper-Glide or Hyper-Form balloons (MicroTherapeutics, Irvine, CA) was successfully accomplished in 88.9% vasospastic segments (48 of 54), namely, in the distal internal carotid artery (100%, n=7), the middle cerebral artery (100%), including the M1 (n=10), M2 (n=10), and M3 segments (n=4), in the vertebral artery (100%, n=2), basilar artery (100%, n=1), and in the anterior cerebral artery (ACA), including the A1 (66%), A2 (66%), and A3 segments (100%). Vessel diameters significantly increased after TBA. There were no cases of vessel rupture or thromboembolic complications. GCS at one day after TBA showed an improvement in all patients except one.

CONCLUSION

This study suggests that TBA using Hyper-Glide or Hyper-Form balloons is a safe and effective treatment for subarachnoid hemorrhage-induced cerebral vasospasm.

Resistant vasospasm in subarachnoid hemorrhage treated with continuous intraarterial nimodipine infusion

Cerebral vasospasm complicating aneurysmal subarachnoid hemorrhage is a well-known medical entity. The delayed ischemic neurological deficits (DIND) as a result of vasospasm remain the main cause of morbidity among patients who manage to survive this severe disease pattern. When the traditional treatment options, either medical or interventional, fail to reverse vasospasm, continuous intraarterial infusion of nimodipine through catheters directly into the spastic arteries presents a promising treatment modality. Of 73 patients with aneurysmal subarachnoid hemorrhage between 2008 and 2009, a total of 27 had Hunt and Hess grades of 4 and 5. Fifteen percent of them showed refractory vasospasms and were treated with continuous nimodipine infusion via catheters in both internal carotid arteries. We present the method's indications and possible complications.

Recurrent vasospasm after endovascular treatment in subarachnoid hemorrhage

OBJECTIVES

the frequency and predictors of recurrent symptomatic and angiographic vasospasm after angioplasty or intra-arterial chemical vasodilatation (IACV) in patients with subarachnoid hemorrhage (SAH) are not well characterized.

METHODS

a retrospective review of serial clinical and angiographic data was conducted between 7/2001-6/2008 on spontaneous SAH patients who underwent endovascular therapy for symptomatic vasospasm.

RESULTS

of 318 SAH patients, symptomatic vasospasm occurred in 80 (25%) and endovascular intervention was performed on 69 (22%) patients. Of these 69 patients, all received IACV in 274 vessels and 33 also underwent angioplasty in a total of 76 vessels. Recurrent angiographic vasospasm occurred in the same vessel segment in 9/23 (39%) patients who received both angioplasty + IACV compared to 40/49 (82%) of patients who received IACV alone (P < 0.001). Recurrent symptomatic vasospasm occurred in 10/26 (38%) angioplasty + IACV patients compared to 28/37 (76%) patients who received IACV alone (P = 0.003). The modified-Fisher Score, A1 spasm, distal and multi-vessel vasospasm predicted recurrent angiographic spasm after IACV alone (P < 0.05). Procedural complications occurred in 4% of IACV alone patients and 6% of angioplasty + IACV patients (P = 0.599).

CONCLUSIONS

recurrent angiographic or symptomatic vasospasm is not uncommon after angioplasty + IACV, but appears to occur significantly less than after IACV alone, without any increase in procedural complications.

Endovascular treatment of medically refractory cerebral vasospasm following aneurysmal subarachnoid hemorrhage

BACKGROUND AND PURPOSE

CV following aneurysmal SAH is a significant cause of morbidity and mortality. We review our experiences using PTA and IA verapamil infusion for treating medically refractory cases.

MATERIALS AND METHODS

We performed a retrospective review of patients with SAH admitted from July 2003 to January 2008.

RESULTS

Of 546 patients admitted within 72 hours of symptom onset, 231 patients (42%) developed symptomatic CV and 189 patients (35%) required endovascular therapy. A total of 346 endovascular sessions were performed consisting of 1 single angioplasty, 286 IA verapamil infusions, and 59 combined treatments. PTA was performed on 151 vessel segments, and IA verapamil was infused in 720 vessel segments. IA verapamil doses ranged from 2.0 to 30.0 mg per vessel segment and from 3.0 to 55.0 mg per treatment session. Repeat treatments were necessary in 102 patients (54%) for persistent, recurrent, or worsening CV. There were 6 treatment-related complications, of which 2 resulted in clinical worsening. No deaths were attributable to endovascular therapy. At follow-up, 115 patients (61%) had a good outcome and 55 patients (29%) had a poor outcome. Sixteen patients died from causes related to SAH, while 3 died from other medical complications.

CONCLUSIONS

Endovascular treatments are an integral part of managing patients with medically refractory CV. In our experience, PTA and IA verapamil are safe, with a low complication rate, but further studies are required to determine appropriate patient selection and treatment efficacy.

[Carotid dissection during angioplasty for vasospasm induced by subarachnoid haemorrhage. The use of multimodal cerebral monitoring]

We report the case of a 54-year-old woman presenting subarachnoid haemorrhage. She experienced multiple vasospasms and treatment included triple-H (hypervolaemia, hypertension, and haemodilution) and endovascular therapies. Right internal carotid dissection complicated angioplasty of the right middle cerebral artery. Combined brain tissue partial pressure of oxygen monitoring and transcranial echo-Doppler could have facilitated early diagnosis. Despite successful revascularization of right internal carotid by stenting, this complication caused acute stroke with refractory intracranial hypertension.

Endothelial nitric oxide synthase tagging single nucleotide polymorphisms and recovery from aneurysmal subarachnoid hemorrhage

Aneurysmal subarachnoid hemorrhage (SAH) is a hemorrhagic stroke subtype with a poor recovery profile. Cerebral vasospasm (CV), a narrowing of the cerebral vasculature, significantly contributes to the poor recovery profile. Variation in the endothelial nitric oxide (NO) synthase (eNOS) gene has been implicated in CV and outcome after SAH. The purpose of this project was to explore the potential association between three eNOS tagging single nucleotide polymorphisms (SNPs) and recovery from SAH. We included 195 participants with a diagnosis of SAH and DNA and 6-month outcome data available but without preexisting neurologic disease/deficit. Genotyping was performed using an ABI Prism 7000 Sequence Detection System and TaqMan assays. CV was verified by cerebral angiogram independently read by a neurosurgeon on 118 participants. Modified Rankin Scores (MRS) and Glasgow Outcome Scale (GOS) scores were collected 6 months posthemorrhage. Data were analyzed using descriptive statistics, analysis of variance (ANOVA) and chi-square analysis as appropriate. The sample was primarily female (n=147; 75.4%) and White (n=178; 91.3%) with a mean age of 54.6 years. Of the participants with CV data, 56 (47.5%) developed CV within 14 days of SAH. None of the SNPs individually were associated with CV presence; however, a combination of the three variant SNPs was significantly associated with CV (p=.017). Only one SNP (rs1799983, variant allele) was associated with worse 6-month GOS scores (p<.001) and MRS (p<.001). These data indicate that the eNOS gene plays a role in the response to SAH, which may be explained by an influence on CV.

Endovascular options in the treatment of delayed ischemic neurological deficits due to cerebral vasospasm

The second leading cause of death and disability in patients with aneurysmal subarachnoid hemorrhage (SAH) is delayed cerebral ischemia due to vasospasm. Although up to 70% of patients have been shown to have angiographic evidence of vasospasm, only 20-30% will present with clinical changes, including mental status changes and neurological deficits that necessitate acute management. Endovascular capabilities have progressed to become viable options in the treatment of cerebral vasospasm. The rationale for intraarterial therapy includes the fact that morbidity and mortality rates have not changed in recent years despite optimized noninvasive medical care. In this report, the authors discuss the most common endovascular options-namely intraarterial vasodilators and transluminal balloon angioplasty-from the standpoint of mechanism, efficacy, limitations, and complications as well as the treatment algorithms for cerebral vasospasm used at our institution.

Cerebral vasospasm following subarachnoid hemorrhage: time for a new world of thought

OBJECTIVE

Delayed cerebral vasospasm has long been recognized as an important cause of poor outcome after an otherwise successful treatment of a ruptured intracranial aneurysm, but it remains a pathophysiological enigma despite intensive research for more than half a century.

METHOD

Summarized in this review are highlights of research from North America, Europe and Asia reflecting recent advances in the understanding of delayed ischemic deficit.

RESULT

It will focus on current accepted mechanisms and on new frontiers in vasospasm research.

CONCLUSION

A key issue is the recognition of events other than arterial narrowing such as early brain injury and cortical spreading depression and of their contribution to overall mortality and morbidity.

Management of aneurysmal subarachnoid hemorrhage

OBJECTIVE

Acute aneurysmal subarachnoid hemorrhage (SAH) is a complex multifaceted disorder that plays out over days to weeks. Many patients with SAH are seriously ill and require a prolonged intensive care unit stay. Cardiopulmonary complications are common. The management of patients with SAH focuses on the anticipation, prevention, and management of these secondary complications.

DATA SOURCES

Source data were obtained from a PubMed search of the medical literature.

DATA SYNTHESIS AND CONCLUSION

The rupture of an intracranial aneurysm is a sudden devastating event with immediate neurologic and cardiac consequences that require stabilization to allow for early diagnostic angiography. Early complications include rebleeding, hydrocephalus, and seizures. Early repair of the aneurysm (within 1-3 days) should take place by surgical or endovascular means. During the first 1-2 weeks after hemorrhage, patients are at risk of delayed ischemic deficits due to vasospasm, autoregulatory failure, and intravascular volume contraction. Delayed ischemia is treated with combinations of volume expansion, induced hypertension, augmentation of cardiac output, angioplasty, and intra-arterial vasodilators. SAH is a complex disease with a prolonged course that can be particularly challenging and rewarding to the intensivist.

[Endovascular treatment of cerebral vasospasm due to aneurysmal subarachnoid hemorrhage]

Cerebral vasospasm remains a leading cause of death and disability in patients with aneurysmal subarachnoid hemorrhage. When vasospasm becomes refractory to maximal medical treatment, endovascular therapies may be considered as an option to increase cerebral blood flow to prevent cerebral infarction. Endovascular techniques include transluminal balloon angioplasty and intra-arterial infusion of vasorelaxants. This article reviews the various endovascular techniques for the treatment of cerebral vasospasm and discusses the mechanisms of action, techniques of administration, clinical results, and limitations of these treatment strategies.