Nicardipine in the treatment of aneurysmal subarachnoid haemorrhage: a meta-analysis of published data

Beyond nimodipine: advanced neuroprotection strategies for aneurysmal subarachnoid hemorrhage vasospasm and delayed cerebral ischemia

The clinical management of aneurysmal subarachnoid hemorrhage (SAH)-associated vasospasm remains a challenge in neurosurgical practice, with its prevention and treatment having a major impact on neurological outcome. While considered a mainstay, nimodipine is burdened by some non-negligible limitations that make it still a suboptimal candidate of pharmacotherapy for SAH. This narrative review aims to provide an update on the pharmacodynamics, pharmacokinetics, overall evidence, and strength of recommendation of nimodipine alternative drugs for aneurysmal SAH-associated vasospasm and delayed cerebral ischemia. A PRISMA literature search was performed in the PubMed/Medline, Web of Science, ClinicalTrials.gov, and PubChem databases using a combination of the MeSH terms "medical therapy," "management," "cerebral vasospasm," "subarachnoid hemorrhage," and "delayed cerebral ischemia." Collected articles were reviewed for typology and relevance prior to final inclusion. A total of 346 articles were initially collected. The identification, screening, eligibility, and inclusion process resulted in the selection of 59 studies. Nicardipine and cilostazol, which have longer half-lives than nimodipine, had robust evidence of efficacy and safety. Eicosapentaenoic acid, dapsone and clazosentan showed a good balance between effectiveness and favorable pharmacokinetics. Combinations between different drug classes have been studied to a very limited extent. Nicardipine, cilostazol, Rho-kinase inhibitors, and clazosentan proved their better pharmacokinetic profiles compared with nimodipine without prejudice with effective and safe neuroprotective role. However, the number of trials conducted is significantly lower than for nimodipine. Aneurysmal SAH-associated vasospasm remains an area of ongoing preclinical and clinical research where the search for new drugs or associations is critical.

Not Your Typical Thunderclap Headache

We present the case of a young adult female who presented to the emergency department with headache and vomiting. After treatment with intravenous fluids, diphenhydramine and metoclopramide the headache completely resolved. Because of the patient's persistent symptoms and past medical history of systemic lupus erythematosus, a noncontrast head CT scan was done. In this case, the patient had a subarachnoid hemorrhage with edema and mass effect, detected on a noncontrast head CT scan. The patient required a nicardipine drip for blood pressure control. The patient recovered well and was discharged at her normal state of health. This case demonstrates the importance of maintaining high clinical suspicion for life-threatening emergencies even in patients with unremarkable physical exams who experience symptomatic improvement after treatment.

Comparative Study of Vasodilatation After Intra-arterial Nicardipine or Dantrolene Infusion in Animal Model of Cerebral Vasospasm

PURPOSE

Intra-arterial (IA) infusion of calcium channel blockers (CCBs) has been widely applied in treating medically refractory vasospasm; however, surprisingly little is known regarding their vasodilatory duration. This study was undertaken to compare attributes of nicardipine and dantrolene, focusing on efficacy and capacity for sustained vasodilation.

METHODS

In New Zealand white rabbits (N = 22), vasospasm was individually provoked through experimentally induced subarachnoid hemorrhage and confirmed via conventional angiography, grouping animals by IA-infused drug (nicardipine vs. dantrolene). Controls received normal saline. After chemoangioplasty, follow-up angiography was performed at intervals of 1-3 h for 6 h to compare vasospastic and dilated (i.e., treated) arterial diameters. Drug efficacy, duration of action, and changes in mean arterial pressure (relative to baseline) were analyzed by group.

RESULTS

Compared with controls, effective vasodilation was evident in both nicardipine and dantrolene test groups after IA infusion. Vasodilatory effects of nicardipine peaked at 1 h, returning to former vasospastic states at 3 h. In dantrolene recipients, vasodilation endured longer, lasting >6 h. Only the nicardipine group showed a significant 3‑h period of lowered blood pressure.

CONCLUSION

Unlike the vasodilatory action of a CCB, sustained for < 3 h after IA infusion, the effect of dantrolene endured for > 6 h. This outcome suggests that IA dantrolene infused alone or together with a conventional CCB infusion may be a new means of prolonging vasodilatory effect. Further research is needed to assess durations of IA-infused vasodilatory drug based on perfusion status.

Nicardipine Prolonged Release Implants for Prevention of Delayed Cerebral Ischemia after Aneurysmal Subarachnoid Hemorrhage: A Meta-Analysis

OBJECTIVES

A paucity of treatments to prevent delayed cerebral ischemia (DCI) has stymied recovery after aneurysmal subarachnoid hemorrhage (aSAH). Nicardipine has long been recognized as a potent cerebrovascular vasodilator with a history off-label use to prevent vasospasm and DCI. Multiple centers have developed nicardipine prolonged release implants (NPRI) that are directly applied during clip ligation to locally deliver nicardipine throughout the vasospasm window. Here we perform a systematic review and meta-analysis to assess whether NPRI confers protection against DCI and improves functional outcomes after aSAH.

MATERIALS AND METHODS

A systematic search of PubMed, Ovid Embase, and Cochrane databases was performed for studies reporting the use of NPRI after aSAH published after January 1, 1980. We included all studies assessing the association of NPRI with DCI and or functional outcomes. Findings from studies with control arms were analyzed using a random effects model. A separate network meta-analysis was performed, including controlled NPRI studies, single-arm NPRI reports, and the control-arms of modern aSAH randomized clinical trials as additional comparators.

RESULTS

The search identified 214 unique citations. Three studies with 284 patients met criteria for the random effects model. The pooled summary odds ratio for the association of NPRI and DCI was 0.21 (95% CI 0.09-0.49, p = 0.0002) with no difference in functional outcomes (OR 1.80, 95% CI 0.63 - 5.16, p = 0.28). 10 studies of 866 patients met criteria for the network meta-analysis. The pooled summary odds ratio for the association of NPRI and DCI was 0.30 (95% CI 0.13-0.89,p = 0.017) with a trend towards improved functional outcomes (OR 1.68, 0.63 - 4.13 95% CI, p = 0.101).

CONCLUSIONS

In these meta-analyses, NPRI decreases the incidence of DCI with a non-significant trend towards improvement in functional outcomes. Randomized trials on the role of intrathecal calcium channel blockers are warranted to evaluate these observations in a prospective manner.

An overview of pharmacotherapy for cerebral vasospasm and delayed cerebral ischemia after subarachnoid hemorrhage

Introduction: Survival from aneurysmal subarachnoid hemorrhage has increased in the past few decades. However, functional outcome after subarachnoid hemorrhage is still suboptimal. Delayed cerebral ischemia (DCI) is one of the major causes of morbidity.Areas covered: Mechanisms underlying vasospasm and DCI after aneurysmal subarachnoid hemorrhage and pharmacological treatment are summarized in this review.Expert opinion: Oral nimodine, an L-type dihydropyridine calcium channel blocker, is the only FDA-approved drug for the prevention and treatment of neurological deficits after aneurysmal subarachnoid hemorrhage. Fasudil, a potent Rho-kinase inhibitor, has also been shown to improve the clinical outcome and has been approved in some countries for use in patients with aneurysmal subarachnoid hemorrhage. Although other drugs, including nicardipine, cilostazol, statins, clazosentan, magnesium and heparin, have been expected to have beneficial effects on DCI, there has been no convincing evidence supporting the routine use of those drugs in patients with aneurysmal subarachnoid hemorrhage in clinical practice. Further elucidation of the mechanisms underlying DCI and the development of effective therapeutic strategies for DCI, including combination therapy, are necessary to further improve the functional outcome and mortality after subarachnoid hemorrhage.

Duration of Vasodilatory Action After Intra-arterial Infusions of Calcium Channel Blockers in Animal Model of Cerebral Vasospasm

BACKGROUND

In medically refractory vasospasm, invasive intervention may be required. A commonly used approach is intra-arterial (IA) drug infusion. Although calcium channel blockers (CCBs) have been widely applied in this setting, studies comparing their efficacies and durations of action have been few. This study was performed to compare attributes of three CCBs (nicardipine, nimodipine, and verapamil), focusing on duration of the vasodilatory action based on angiography.

METHODS

Vasospasm was produced in New Zealand white rabbits (N = 22) through experimentally induced subarachnoid hemorrhage and confirmed in each via conventional angiography, grouping them by IA-infused drug. After chemoangioplasty, angiography was performed hourly for 5 h to compare dilated and vasospastic arterial diameters. Drug efficacy, duration of action, and changes in mean arterial pressure (relative to baseline) were analyzed by group.

RESULTS

Effective vasodilation was evident in all three groups immediately after IA drug infusion. The vasodilative effects of nimodipine and nicardipine peaked at 1 h and were sustained at 2 h, returning to initial vasospastic states at 3 h. In verapamil recipients, effects were more transient by comparison, entirely dissipating at 1 h. Only the nicardipine group showed a significant 3-h period of lowered blood pressure.

CONCLUSIONS

Although nimodipine and nicardipine proved longer acting than verapamil in terms of vasodilation, their effects were not sustained beyond 2 h after IA infusion. Further study is required to confirm the vasodilatory duration of IA CCB based on perfusion status, and an effort should be made to find new alternative to extend the duration.

Cerebral vasospasm: current understanding

PURPOSE OF REVIEW

With recent research trying to explore the pathophysiologic mechanisms behind vasospasm, newer pharmacological and nonpharmacological treatments are being targeted at various pathways involved. This review is aimed at understanding the mechanisms and current and future therapies available to treat vasospasm.

RECENT FINDINGS

Computed tomography perfusion is a useful alternative tool to digital subtraction angiography to diagnose vasospasm. Various biomarkers have been tried to predict the onset of vasospasm but none seems to be helpful. Transcranial Doppler still remains a useful tool at the bedside to screen and follow up patients with vasospasm. Hypertension rather than hypervolemia and hemodilution in 'Triple-H' therapy has been found to be helpful in reversing the vasospasm. Hyperdynamic therapy in addition to hypertension has shown promising effects. Endovascular approaches with balloon angioplasty and intra-arterial nimodipine, nicardipine, and milrinone have shown consistent benefits. Endothelin receptor antagonists though relieved vasospasm, did not show any benefit on functional outcome.

SUMMARY

Endovascular therapy has shown consistent benefit in relieving vasospasm. An aggressive combination therapy through various routes seems to be the most useful approach to reduce the complications of vasospasm.

Cerebral artery myogenic reactivity: The next frontier in developing effective interventions for subarachnoid hemorrhage

Aneurysmal subarachnoid hemorrhage (SAH) is a devastating cerebral event that kills or debilitates the majority of those afflicted. The blood that spills into the subarachnoid space stimulates profound cerebral artery vasoconstriction and consequently, cerebral ischemia. Thus, once the initial bleeding in SAH is appropriately managed, the clinical focus shifts to maintaining/improving cerebral perfusion. However, current therapeutic interventions largely fail to improve clinical outcome, because they do not effectively restore normal cerebral artery function. This review discusses emerging evidence that perturbed cerebrovascular "myogenic reactivity," a crucial microvascular process that potently dictates cerebral perfusion, is the critical element underlying cerebral ischemia in SAH. In fact, the myogenic mechanism could be the reason why many therapeutic interventions, including "Triple H" therapy, fail to deliver benefit to patients. Understanding the molecular basis for myogenic reactivity changes in SAH holds the key to develop more effective therapeutic interventions; indeed, promising recent advancements fuel optimism that vascular dysfunction in SAH can be corrected to improve outcome.

Prolonged Intracisternal Papaverine Toxicity: Index Case Description and Proposed Mechanism of Action

BACKGROUND

Intracisternal papaverine (iPPV) is a vasodilator used for prophylaxis of intraoperative vasospasm during aneurysmal clipping. Postoperative side effects of iPPV include transient cranial nerve palsies, most commonly mydriasis owing to oculomotor nerve involvement, with rapid resolution.

METHODS

We critically reviewed current literature on the adverse effects of iPPV in aneurysmal surgery with a focus on oculomotor nerve involvement. We also present the index case of prolonged bilateral mydriasis secondary to iPPV irrigation toxicity and its putative underlying mechanism.

RESULTS

Papaverine toxicity occurs in the setting of its antimuscarinic action and blood-cerebrospinal fluid and blood-brain barrier compromise owing to acute subarachnoid hemorrhage and direct effect of papaverine. Our patient also experienced severe vasospasm and a minor stroke, both contributing to further blood-brain barrier disruption, and relatively acidic pH of the subarachnoid hemorrhage milieu.

CONCLUSIONS

We propose that these factors perpetuate phase dynamics of papaverine crystals and facilitate a sustained slow release of papaverine within the cisternal system. Were it indicated, 0.3% iPPV would reasonably diminish the risk for neurotoxicity.

Higher dose intra-arterial milrinone and intra-arterial combined milrinone-nimodipine infusion as a rescue therapy for refractory cerebral vasospasm

Background Cerebral vasospasm (CV) is a major cause of delayed morbidity and mortality in patients with subarachnoid hemorrhage (SAH). Various cerebral protectants have been tested in patients with aneurysmal SAH. We aimed to research the success rate of treatment of CV via intra-arterial milrinone injection and aggressive pharmacological therapy for refractory CV. Methods A total of 25 consecutive patients who received intra-arterial milrinone and nimodipine treatment for CV following SAH between 2014 and 2017 were included in the study. Patients who underwent surgical clipping were excluded. Refractory vasospasm was defined as patients with CV refractory to therapies requiring ≥3 endovascular interventions. Overall, six patients had refractory CV. Long-term neurological outcome was assessed 6-18 months after SAH using a modified Rankin score and Barthel index. Results The median modified Rankin scores were 1 (min: 0, max: 3) and Barthel index scores were 85 (min: 70, max: 100) From each vasospastic territory maximal 10-16 mg milrinone was given to patients; a maximum of 24 mg milrinone was given to each patient in a session and a maximum of 42 mg milrinone was given to a patient in a day. Both milrinone and nimodipine were given to three patients. There was a large vessel diameter increase after milrinone and nimodipine injections. No patient died due to CV; only one patient had motor dysfunction on the right lower extremity. Conclusion Higher doses of milrinone can be used effectively to control refractory CV. For exceptional patients with refractory CV, high dose intra-arterial nimodipine and milrinone infusion can be used as a rescue therapy.

Chemical angioplasty with spasmolytics for vasospasm after subarachnoid hemorrhage

BACKGROUND

Clinically symptomatic vasospasm leading to delayed ischemic neurological deficits occurs in up to 30% of patients with subarachnoid hemorrhage (SAH). Vasospasm can result in a serious decline in clinical conditions of patients with SAH, yet the algorithm for vasospasm treatment and prevention remains unclear. Intra-arterial administration of vasodilators is one of the modalities used for vasospasm therapy.

METHODS

Over the last 7 years, we have treated 27 female and 7 male patients with vasospasm using intra-arterial administration of either nimodipine or milrinone; all had suffered aneurysm rupture. Of these patients, 28 were treated surgically (clip), and 6 patients had their aneurysm coiled. Spasmolytics were applied from day 2 to day 18 after rupture.

RESULTS

Of the 53 procedures, angiographic improvement was documented in 92% of cases with a mean flow velocity decrease of 65 cm/s. Brain metabolism changes were monitored after the procedure. The highest level of immediate clinical improvement was observed in conscious patients with a focal neurological deficit (aphasia, hemiparesis). Overall clinical outcomes (Glasgow outcome scale, GOS) were as follows: GOS 5 (12 patients), GOS 4 (5 patients), GOS 3 (5 patients), GOS 2 (6 patients), and GOS 1 (6 patients).

CONCLUSIONS

Intra-arterial administration of spasmolytics is a safe and potent method of vasospasm treatment. It is most effective when applied to conscious patients with a focal deficit. For unconscious patients, its therapeutic benefits are inconclusive. Patients in severe clinical states would further require use of other diagnostic tools such as multimodal brain monitoring to complement vasospasm therapy.

Temporal evolution of vasospasm and clinical outcome after intra-arterial vasodilator therapy in patients with aneurysmal subarachnoid hemorrhage

Intra-arterial (IA) vasodilator therapy is one of the recommended treatments to minimize the impact of aneurysmal subarachnoid hemorrhage-induced cerebral vasospasm refractory to standard management. However, its usefulness and efficacy is not well established. We evaluated the effect IA vasodilator therapy on middle cerebral artery blood flow and on discharge outcome. We reviewed records for 115 adults admitted to Neurointensive Care Unit to test whether there was a difference in clinical outcome (discharge mRS) in those who received IA infusions. In a subset of 19 patients (33 vessels) treated using IA therapy, we tested whether therapy was effective in reversing the trends in blood flow. All measures of MCA blood flow increased from day -2 to -1 before infusion (maximum Peak Systolic Velocity (PSV) 232.2±9.4 to 262.4±12.5 cm/s [p = 0.02]; average PSV 202.1±8.5 to 229.9±10.9 [p = 0.02]; highest Mean Flow Velocity (MFV) 154.3±8.3 to 172.9±10.5 [p = 0.10]; average MFV 125.5±6.3 to 147.8±9.5 cm/s, [p = 0.02]) but not post-infusion (maximum PSV 261.2±14.6 cm/s [p = .89]; average PSV 223.4±11.4 [p = 0.56]; highest MFV 182.9±12.4 cm/s [p = 0.38]; average MFV 153.0±10.2 cm/s [p = 0.54]). After IA therapy, flow velocities were consistently reduced (day X infusion interaction p<0.01 for all measures). However, discharge mRS was higher in IA infusion group, even after adjusting for sex, age, and admission grades. Thus, while IA vasodilator therapy was effective in reversing the vasospasm-mediated deterioration in blood flow, clinical outcomes in the treated group were worse than the untreated group. There is need for a prospective randomized controlled trial to avoid potential confounding effect of selection bias.

Cerebral Vasospasm in Subarachnoid Hemorrhage Through Aneurysm Rupture - Clinical Considerations and Case Report

Arterial aneurysm ruptures of the circle of Willis determine subarachnoid hemorrhage, which evolving due to the irritating effect of the blood in the subarachnoid space may lead to complications such as large arterial vasospasm in the origin of the large cerebral arteries, from the base of the brain.

Cerebral vasospasm causes a downstream cerebral ischemia, that may lead to the establishment of an ischemic stroke which is life threatening.

Early treatment against the vasospasm with calcium channels blockers should prevent occurrence of ischemia. However, the effectiveness of this treatment is not fully confirmed, fact that was mentioned even in the presentation of our case.

The evidence for a role of vasospasm in the pathogenesis of cerebral malaria

Due to delay in treatment, cerebral malaria (CM) remains a significant complication of Plasmodium falciparum infection and is a common cause of death from malaria. In addition, more than 10 % of children surviving CM have neurological and long-term cognitive deficits. Understanding the pathogenesis of CM enables design of supportive treatment, reducing neurological morbidity and mortality. Vaso-occlusion and brain swelling appear to be leading to clinical features, neuronal damage and death in CM. It is proposed that parasitized red blood cells (pRBC), due to cytoadhesion to the endothelium and vasospasm induced by reduced bioavailability of nitric oxide, are causes. Stasis of blood flow and accumulation of pRBC may allow, after schizont rupture, for high concentration of products of haemolysis to accumulate, which leads to localized nitric oxide depletion, inducing adhesion molecules and cerebral vasospasm. Features consistent with an involvement of vasospasm are rapid reversibility of neurological symptoms, intermittently increased or absent flow in medium cerebral artery detectable on Doppler ultrasound and hemispheric reversible changes on cerebral magnetic resonance imaging in some patients. Clinical trials of treatment that can rapidly reduce cerebral vasospasm, including nitric oxide donors, inhaled nitric oxide, endothelin or calcium antagonists, or tissue plasminogen activators, are warranted.

Impact of preadmission treatment with calcium channel blockers or beta blockers on short-term mortality after stroke: a nationwide cohort study

Background

The prognostic impact of preadmission use of calcium channel blockers (CCBs) and beta blockers (BBs) on stroke mortality remains unclear. We aimed to examine whether preadmission use of CCBs or BBs was associated with improved short-term mortality following ischemic stroke, intracerebral hemorrhage (ICH), or subarachnoid hemorrhage (SAH).

Methods

We conducted a nationwide population-based cohort study using Danish medical registries. We identified all patients with a first-time inpatient diagnosis of stroke between 2004 and 2012 and their comorbidities. We defined CCB/BB use as current use, former use, or non-use. Current use was further classified as new or long-term use. We used Cox regression modeling to compute 30-day mortality rate ratios (MRRs) with 95% confidence intervals (CIs), controlling for potential confounders.

Results

We identified 100,043 patients with a first-time stroke. Of these, 83,736 (83.7%) patients had ischemic stroke, 11,779 (11.8%) had ICH, and 4,528 (4.5%) had SAH. Comparing current users of CCBs or BBs with non-users, we found no association with mortality for ischemic stroke [adjusted 30-day MRR = 0.99 (95% CI: 0.94-1.05) for CCBs and 1.01 (95% CI: 0.96-1.07) for BBs], ICH [adjusted 30-day MRR = 1.05 (95% CI: 0.95-1.16) for CCBs and 0.95 (95% CI: 0.87-1.04) for BBs], or SAH [adjusted 30-day MRR = 1.05 (95% CI: 0.85-1.29) for CCBs and 0.89 (95% CI: 0.72-1.11) for BBs]. Former use of CCBs or BBs was not associated with mortality.

Conclusions

Preadmission use of CCBs or BBs was not associated with 30-day mortality following ischemic stroke, ICH, or SAH.

Electronic supplementary material

The online version of this article (doi:10.1186/s12883-015-0279-3) contains supplementary material, which is available to authorized users.

Vasospasm in cerebral inflammation

All forms of cerebral inflammation as found in bacterial meningitis, cerebral malaria, brain injury, and subarachnoid haemorrhage have been associated with vasospasm of cerebral arteries and arterioles. Vasospasm has been associated with permanent neurological deficits and death in subarachnoid haemorrhage and bacterial meningitis. Increased levels of interleukin-1 may be involved in vasospasm through calcium dependent and independent activation of the myosin light chain kinase and release of the vasoconstrictor endothelin-1. Another key factor in the pathogenesis of cerebral arterial vasospasm may be the reduced bioavailability of the vasodilator nitric oxide. Therapeutic trials in vasospasm related to inflammation in subarachnoid haemorrhage in humans showed a reduction of vasospasm through calcium antagonists, endothelin receptor antagonists, statins, and plasminogen activators. Combination of therapeutic modalities addressing calcium dependent and independent vasospasm, the underlying inflammation, and depletion of nitric oxide simultaneously merit further study in all conditions with cerebral inflammation in double blind randomised placebo controlled trials. Auxiliary treatment with these agents may be able to reduce ischemic brain injury associated with neurological deficits and increased mortality.