Fawaz Al-Mufti

Ultra-early angiographic vasospasm associated with delayed cerebral ischemia and infarction following aneurysmal subarachnoid hemorrhage.

OBJECTIVE The clinical significance of cerebral ultra-early angiographic vasospasm (UEAV), defined as cerebral arterial narrowing within the first 48 hours of aneurysmal subarachnoid hemorrhage (aSAH), remains poorly characterized. The authors sought to determine its frequency, predictors, and impact on functional outcome. METHODS The authors prospectively studied UEAV in a cohort of 1286 consecutively admitted patients with aSAH between August 1996 and June 2013. Admission clinical, radiographic, and acute clinical course information was documented during patient hospitalization. Functional outcome was assessed at 3 months using the modified Rankin Scale. Logistic regression and Cox proportional hazards models were generated to assess predictors of UEAV and its relationship to delayed cerebral ischemia (DCI) and outcome. Multiple imputation methods were used to address data lost to follow-up. RESULTS The cohort incidence rate of UEAV was 4.6%. Multivariable logistic regression analysis revealed that younger age, sentinel bleed, and poor admission clinical grade were significantly associated with UEAV. Patients with UEAV had a 2-fold increased risk of DCI (odds ratio [OR] 2.3, 95% confidence interval [CI] 1.4-3.9, p = 0.002) and cerebral infarction (OR 2.0, 95% CI 1.0-3.9, p = 0.04), after adjusting for known predictors. Excluding patients who experienced sentinel bleeding did not change this effect. Patients with UEAV also had a significantly higher hazard for DCI in a multivariable model. UEAV was not found to be significantly associated with poor functional outcome (OR 0.8, 95% CI 0.4-1.6, p = 0.5). CONCLUSIONS UEAV may be less frequent than has been reported previously. Patients who exhibit UEAV are at higher risk for refractory DCI that results in cerebral infarction. These patients may benefit from earlier monitoring for signs of DCI and more aggressive treatment. Further study is needed to determine the long-term functional significance of UEAV.

Neuroendovascular Interventions for Acute Ischemic Strokes in Patients Supported with Left Ventricular Assist Devices: A Single-Center Case Series and Review of the Literature

BACKGROUND With the shortage of donor hearts, increasingly more patients with end-stage heart failure are implanted with left ventricular assist devices (LVADs). LVADs are associated with a significant risk of developing acute ischemic strokes (AISs). Very little is known on about the management of AIS in patients with LVAD, especially with regard to the safety and efficacy of neuroendovascular techniques. METHODS We identified 5 patients with heart failure and LVAD implants who developed AIS and underwent neuroendovascular interventions at Columbia University Medical Center. Their cases were reviewed for the safety, efficacy of the interventions, and potential complications. RESULTS There were no significant complications from the interventions. In all 5 cases, there was at least a 4-point improvement in the National Institutes of Health Stroke scale and none of the cases developed symptomatic hemorrhage. Two patients had substantial improvement and received cardiac transplantations. CONCLUSIONS Neuroendovascular intervention is safe and feasible in patients with LVAD and may potentially contribute to improving the outcome of a disease that has a poor natural history. Further study is recommended.

Symptomatic Infratentorial Thrombosed Developmental Venous Anomaly: Case Report and Review of the Literature

Background: Developmental venous anomalies (DVAs) are variations of normal transmedullary veins draining white and gray matter. In the vast majority of cases, DVAs are diagnosed incidentally and should be considered as benign entities. In extremely rare circumstances, DVAs may become symptomatic due to mechanical or flow-related etiologies. Thrombosis of the collector vein of a DVA is a rare type of a flow-related complication with only 29 cases reported in the literature, the majority of which are supratentorial. Infratentorial thrombosed DVAs are thus extremely rare and the few cases reported have typically caused symptoms due to venous ischemic infarctions. Summary: We report a case of an infratentorial DVA with a thrombosed drainage vein in a patient with nonhemorrhagic, noninfarcted venous congestive edema, which was successfully treated with high-dose glucocorticoids and short-term anticoagulation. We review the pertinent venous anatomy of the posterior fossa as well as the literature of symptomatic infratentorial thrombosed DVAs. Key Message: The presented case of an infratentorial thrombosed DVA with cerebellar and pontine venous congestive edema is extremely rare. A working knowledge of posterior fossa venous anatomy and possible pathomechanisms responsible for the rarely symptomatic lesion will aid in the timely and efficacious treatment of such lesions.

Neurocritical Care of Emergent Large-Vessel Occlusion The Era of a New Standard of Care

Acute ischemic stroke continues to be one of the leading causes of morbidity and mortality worldwide. Recent advances in mechanical thrombectomy techniques combined with prereperfusion computed tomographic angiography for patient selection have revolutionized stroke care in the past year. Peri- and postinterventional neurocritical care of the patient who has had an emergent large-vessel occlusion is likely an equally important contributor to the outcome but has been relatively neglected. Critical periprocedural management issues include streamlining care to speed intervention, blood pressure optimization, reversal of anticoagulation, management of agitation, and selection of anesthetic technique (ie, general vs monitored anesthesia care). Postprocedural critical care issues that might modulate neurological outcome include blood pressure and glucose optimization, avoidance of fever or hyperoxia, fluid and nutritional management, and early integration of rehabilitation into the intensive care unit setting. In this review, we sought to lay down an evidence-based strategy for patients with acute ischemic stroke undergoing emergent endovascular reperfusion.

Flow Diversion for Intracranial Aneurysm Management: A New Standard of Care

Endovascular treatment of intracranial aneurysms with complex morphologies such as giant, wide-necked, or fusiform aneurysms is challenging. Stent-assisted coiling and balloon-assisted coiling are alternative techniques to treat such complex aneurysms, but studies have shown less-than-expected efficacy, as suggested by their high rate of recanalization. The management of complex aneurysms via microsurgery or conventional neuroendovascular strategies has traditionally been poor. However, over the last few years, flow-diverting stents (FDS) have revolutionized the treatment of such aneurysms. FDS are implanted within the parent artery rather than the aneurysm sac. By modifying intra-aneurysmal and parent-vessel flow dynamics at the aneurysm/parent vessel interface, FDS trigger a cascade of gradual intra-aneurysmal thrombosis. As endothelialization of the FDS is complete, the parent vessel reconstructs while preserving the patency of normal perforators and side branch vessels. As with any intervention, the practice and application of flow-diversion technology is inherent, with risks that include vessel rupture or perforation, in-stent thrombosis, perforator occlusion, procedural and delayed hemorrhages, and perianeurysmal edema. Herein, we review the devices, their mechanisms of actions, clinical applications, complications, and ongoing studies.

Direct carotid-cavernous fistula: A complication of, and treatment with, flow diversion

Direct carotid-cavernous fistulas (CCFs) are rare complications of flow diversion and have typically been documented in a subacute time frame after treatment. We present the first reported case of an intraprocedural direct CCF that developed immediately after flow diversion for treatment of a symptomatic paraclinoid right internal carotid artery aneurysm with a neck involving the cavernous segment. Endovascular treatment of such direct fistulas typically involves either transarterial obliteration of the fistulous site or transvenous embolization of the cavernous sinus. Our case was successfully treated with further immediate flow diversion without additional transvenous intervention. There are few reports on the use of flow diversion for treatment of such direct CCFs, and in all but one of these cases, flow diversion was combined with concomitant transvenous embolization. Thus, the presented case is not only the first reported case of an immediate CCF after flow diversion, but it is also only the second reported case of a direct fistula to be successfully treated using solely flow diversion, without additional transvenous intervention. We review the literature of direct CCFs after flow diversion, the pathophysiology of development of CCFs after flow diversion, the literature on treatment of CCFs with flow diversion as well as all other current treatment options.

Spontaneous Bilateral Carotid-Cavernous Fistulas Secondary to Cavernous Sinus Thrombosis

Bilateral carotid cavernous fistulas are rare entities that can cause debilitating symptoms and can lead to more severe consequences if left untreated. Therefore, the recognition and adequate treatment of these pathologies is very important. We present 2 cases of bilateral carotid cavernous fistulas that arose as a result of cavernous sinus thrombosis. We review the literature and discuss the pathophysiology, symptomatology, management, and treatment of bilateral carotid cavernous fistulas. Within our own cases, treatment of the patients was varied. The patient in case 1 was successfully treated with endovascular therapy after a failed trial of anticoagulation. The patient in case 2 demonstrated resolution of bilateral carotid cavernous fistulas after anticoagulation therapy. Case 2 highlights the fact that certain cases of bilateral carotid cavernous fistulas due to cavernous sinus thrombosis may benefit from extensive anticoagulation therapy. If anticoagulation therapy is unsuccessful, endovascular therapy may prove beneficial in resolving the fistulous shunt.

Emergent carotid stenting and intra-arterial abciximab in acute ischemic stroke due to tandem occlusion

Abstract Objective: Acute occlusions of the extracranial internal carotid artery (ICA) and a major intracranial artery respond poorly to intravenous tissue plasminogen activator (tPA) and present an endovascular challenge. The aim of our study was to retrospectively delineate the feasibility of the combined use of emergent carotid stenting and intra-arterial (IA) Abciximab with intracranial revascularization in the setting of acute ischemic stroke and carotid occlusions at our institution. Methods: Eleven patients with complete cervical carotid occlusion with or without concomitant intracranial ICA and/or MCA occlusion were identified from a single center, retrospective review of patients admitted to the Stroke unit. We evaluated all cases for complications of emergent cervical ICA recanalization employing carotid stenting and IA Abciximab. Results: All patients had complete cervical carotid occlusion with (n = 8) or without (n = 3) concomitant intracranial ICA and/or MCA occlusion. Successful emergent cervical ICA recanalization was achieved in all cases. All patients were administered IA Abciximab (dose range 6–17 mg, average 11.4 mg) immediately following the cervical carotid stenting. There was complete recanalization in all patients with no procedural morbidity or mortality. A single case (1/11, 9%) developed asymptomatic hemorrhagic transformation. Upon discharge, 9 patients (9/11, 82%) had a mRS of 0–2 and 2 patients (2/11, 18%) had a mRS of 3. Conclusions: In acute ICA–MCA/distal ICA occlusions, extracranial stenting followed by intracranial IA Abciximab and thrombectomy appears feasible, effective, and safe. Further evaluation of this treatment strategy is warranted.

Arteriovenous Malformations in the Pediatric Population: Review of the Existing Literature

Arteriovenous malformations (AVMs) in the pediatric population are relatively rare but reportedly carry a higher rate of rupture than in adults. This could be due to the fact that most pediatric AVMs are only detected after rupture. We aimed to review the current literature regarding the natural history and the clinical outcome after multimodality AVM treatment in the pediatric population, as optimal management for pediatric AVMs remains controversial. A multidisciplinary approach using multimodality therapy if needed has been proved to be beneficial in approaching these lesions in all age groups. Microsurgical resection remains the gold standard for the treatment of all accessible pediatric AVMs. Embolization and radiosurgery should be considered as an adjunctive therapy. Embolization provides a useful adjunct therapy to microsurgery by preventing significant blood loss and to radiosurgery by decreasing the volume of the AVM. Radiosurgery has been described to provide an alternative treatment approach in certain circumstances either as a primary or adjuvant therapy.

Hypertonic Saline for Increased Intracranial Pressure After Aneurysmal Subarachnoid Hemorrhage: A Systematic Review

BACKGROUND The use of hyperosmolar agents, such as mannitol or hypertonic saline (HTS), to control high intracranial pressure (ICP) in patients with traumatic brain injury has been well studied. However, the role of HTS in the management of aneurysmal subarachnoid hemorrhage (aSAH)-associated increased ICP is still unclear. METHODS We performed a systematic review in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The primary outcome of this review is to quantify ICP reduction produced by HTS and its effect on clinical outcomes defined by any standardized functional score. Secondary outcomes included HTS versus mannitol in ICP reduction, HTS effects on cerebral vasospasm, and HTS dose concentration, infusion rate, infusion volume, frequency of redosing, and serum sodium/osmolality limits for repeat dosing. RESULTS Five studies were included in the review encompassing 175 patients. Studies on aSAH included mostly poor grade patients (defined as World Federation of Neurosurgical Societies grade 4 and 5). HTS concentrations ranged from 3%-23.5%. Most studies found that HTS decreased ICP when compared with either baseline or placebo. The mean decrease in ICP from HTS administration was 8.9 mm Hg (range: 3.3-12.1 mm Hg). Only 1 study showed possible improvement in poor grade aSAH outcomes. CONCLUSIONS The current evidence suggests that HTS is as effective as mannitol at reducing increased ICP in aSAH. However, there is not enough data to recommend the optimal and safest dose concentration or whether HTS significantly improves outcomes in aSAH.