Omar Kass-Hout

Intravenous Thrombolysis and Endovascular Therapy for Acute Ischemic Stroke With Internal Carotid Artery Occlusion: A Systematic Review of Clinical Outcomes

Background and Purpose— Strokes secondary to acute internal carotid artery (ICA) occlusion are associated with extremely poor prognosis. The best treatment approach to acute stroke in this setting is unknown. We sought to determine clinical outcomes in patients with acute ischemic stroke attributable to ICA occlusion treated with intravenous (IV) systemic thrombolysis or intra-arterial endovascular therapy. Methods— Using the PubMed database, we searched for studies that included patients with acute ischemic stroke attributable to ICA occlusion who received treatment with IV thrombolysis or intra-arterial endovascular interventions. Studies providing data on functional outcomes beyond 30 days and mortality and symptomatic intracerebral hemorrhage (sICH) rates were included in our analysis. We compared the proportions of patients with favorable functional outcomes, sICH, and mortality rates in the 2 treatment groups by calculating &khgr;2 and confidence intervals for odds ratios. Results— We identified 28 studies with 385 patients in the IV thrombolysis group and 584 in the endovascular group. Rates of favorable outcomes and sICH were significantly higher in the endovascular group than the IV thrombolysis-only group (33.6% vs 24.9%, P=0.004 and 11.1% vs 4.9%, P=0.001, respectively). No significant difference in mortality rate was found between the groups (27.3% in the IV thrombolysis group vs 32.0% in the endovascular group; P=0.12). Conclusions— According to our systematic review, endovascular treatment of acute ICA occlusion results in improved clinical outcomes. A higher rate of sICH after endovascular treatment does not result in increased overall mortality rate.

Is Bridging with Intravenous Thrombolysis of Any Benefit in Endovascular Therapy for Acute Ischemic Stroke

OBJECTIVE Large vessel occlusions with heavy clot burden are less likely to improve with intravenous (IV) thrombolysis alone. The purpose of this study was to show whether a combination of IV thrombolysis and endovascular therapy was superior to endovascular treatment alone. METHODS Data for 104 patients with acute large artery occlusion treated between 2005 and 2010 were reviewed. Forty-two received endovascular therapy in combination with IV thrombolysis (bridging group), and 62 received endovascular therapy only. Clinical outcome, mortality rate, and symptomatic intracranial hemorrhage (sICH) rate were compared between the two groups. RESULTS The two groups had similar demographic and vascular risk factor distribution, as well as National Institutes of Health Stroke Scale score on admission (mean±SD: 14.8±4.7 and 16.0±5.3; P=0.23). No difference was found in Thrombolysis in Myocardial Infarction recanalization rates (score of 2 or 3) after combined or endovascular therapy alone (83.33% and 79.03%; P=0.585). Favorable outcome, defined as a modified Rankin Scale score of <2 at 90 days, also did not differ between the bridging group and the endovascular-only group (37.5% and 32.76%; P=0.643). There was no difference in mortality rate (19.04% and 29.03%; P=0.5618) and sICH rate (11.9% and 9.68%; P=0.734). A significant difference was found in mean time from symptom onset to treatment in the bridging group and the endovascular-only group (227±88 min vs. 125±40 min; P<0.0001). CONCLUSION Combining IV thrombolysis with endovascular therapy resulted in similar outcome, revascularization, sICH, and mortality rates compared with endovascular therapy alone. Prospective clinical studies comparing both treatment strategies in acute ischemic stroke are warranted.

A Novel Approach to Diagnose Reversible Cerebral Vasoconstriction Syndrome: A Case Series

BACKGROUND Reversible cerebral vasoconstriction syndrome (RCVS) is classically diagnosed based on the presence of severe thunderclap headache, focal neurologic symptoms, and the radiographic findings of reversible diffuse segmental cerebral vasoconstriction. We present a diagnostic test that may assist in the clinical diagnosis and facilitate treatment. METHODS From October 1, 2010, to August 1, 2013, we identified consecutive patients who presented with a presumptive diagnosis of RCVS and underwent cerebral diagnostic angiography with intra-arterial (IA) vasodilator therapy. Medical records including clinical presentation, radiographic, and angiographic images were all reviewed. RESULTS We identified a total of 7 patients (4 females; age range, 22-56; mean, 45 years) who met our inclusion criteria. Four patients received a combination of milrinone and nicardipine infusion either in the internal carotid arteries or in the left vertebral artery; the remaining patients received IA therapy solely with either nicardipine or milrinone. Five patients had a positive angiographic response, defined as significant improvement or resolution of the blood vessels irregularities. All 5 patients had a definite discharge diagnosis of RCVS. The remaining 2 patients had a negative angiographic response and based on their clinical and radiographic course had a final diagnosis of intracranial atherosclerotic disease. CONCLUSIONS Our small case series suggest that IA administration of vasodilators is safe and may aid in distinguishing vasodilator responsive syndromes such as RCVS from other causes. Further study is required with long-term clinical outcome to determine the utility of this diagnostic test.

Blood Pressure Management and Evolution of Thrombolysis-associated Intracerebral Hemorrhage in Acute Ischemic Stroke

BACKGROUND There is limited knowledge on the radiographic features of thrombolysis-induced hemorrhage. The factors that influence early hematoma expansion have not been elucidated. METHODS Patients presenting with a symptomatic intracerebral hemorrhage (ICH) as a result of intravenous (IV) thrombolysis with tissue plasminogen activator (tPA) for acute ischemic stroke and had noncontrast computed tomographic (CT) scans of the head were included in this retrospective study. Calculation of hematoma volumes was obtained. Analysis of covariance was used to evaluate for the effect of baseline blood pressure (BP) on initial hematoma volume and further growth. RESULTS Of 267 patients who were treated with intravenous tPA for acute ischemic stroke at our facility between January 1, 2005 and December 31, 2009, 17 patients developed symptomatic ICH and were included in the final analysis. There was a positive correlation between baseline level of systolic BP after thrombolysis and initial hematoma volume (r = 0.46; P = .03) but not for the diastolic BP (r = 0.07; P = .40). There was a significant increase in mean hematoma volume expansion when comparing results between the first and second CT scans (median 9 hours, 22 minutes; 14.9 ± 19.6 cm(3) to 26.0 ± 26.7 cm(3); P = .04). There was also a negative association between the reduction of systolic BP and hematoma growth (r = -0.67; P = .02), but no correlation with change in diastolic BP (r = -0.22; P = .28). CONCLUSIONS Once diagnosed, thrombolysis-induced symptomatic ICH undergoes significant early expansion in size. Systolic BP may play a role in hematoma expansion.

Intravenous heparin for the treatment of intraluminal thrombus in patients with acute ischemic stroke: a case series

Background and Objectives Current American Stroke Association/American Heart Association recommendations on the management of acute ischemic stroke do not recommend the early use of heparin because of an increased risk of bleeding complications. However, for select patients, such as those with strokes associated with non-occlusive intraluminal thrombus, intravenous heparin might prove to be beneficial. Methods A retrospective analysis of acute ischemic stroke cases associated with non-occlusive intraluminal thrombus of intracranial and extracranial arteries in the corresponding vascular territories was conducted to identify patients in whom treatment with intravenous heparin resulted in near-complete or complete lysis of the thrombus. Imaging findings from CT perfusion and angiography, MRI, and/or digital subtraction angiography were used to describe the location of intraluminal thrombus immediately before and after treatment with intravenous heparin. Results 18 patients with nonocclusive intraluminal thrombus confirmed by CT angiography (CTA) received treatment with intravenous heparin alone (median duration 3.5 days; range 1–8 days). The median National Institutes of Health stroke scale score was 2.5 (range 0–15) on admission and 1 (range 0–9) at discharge. Nine patients had complete lysis, and nine patients had partial lysis of the thrombus with improved flow distal to the location of the thrombus. None of the patients developed intracranial hemorrhage. Conclusion For strokes associated with intraluminal thrombus, intravenous heparin might prove to be an effective treatment strategy. Further studies are necessary to evaluate the efficacy and safety of treatment with intravenous heparin in those patients.

Longer procedural times are independently associated with symptomatic intracranial hemorrhage in patients with large vessel occlusion stroke undergoing thrombectomy

Background Time to reperfusion is an essential factor in determination of outcomes in acute ischemic stroke (AIS). Objective To establish the effect of the procedural time on the clinical outcomes of patients with AIS. Methods Data from all consecutive patients who underwent mechanical thrombectomy between September 2010 and July 2012 were analysed retrospectively. The variable of interest was procedural time (defined as time from groin puncture to final recanalization time). Outcome measures included the rates of symptomatic intracranial hemorrhage (sICH, defined as any parenchymal hematoma—eg, PH-1/PH-2), final infarct volume, 90-day mortality, and independent functional outcomes (modified Rankin Scale 0–2) at 90 days. Results The cohort included 242 patients with a mean age of 65.5±14.2 and median baseline National Institutes of Health Stroke Scale score 20. 51% of the patients were female. The mean procedure time was significantly shorter in patients with a good outcome (86.7 vs 73.1 min, respectively, p=0.0228). Patients with SICH had significantly higher mean procedure time than patients without SICH (79.67 vs 104.5 min, respectively; p=0.0319), which remained significant when controlling for the previous factors (OR=0.974, 95% CI 0.957 to 0.991). No correlation was found between the volume of infarction and the procedure time (r=0.10996, p=0.0984). No association was seen between procedure time and 90-day mortality (77.8 vs 88.2 min in survivals vs deaths, respectively; p=0.0958). Conclusions Our data support an association between the risk of SICH and a longer procedure time, but no association between procedural times and the final infarction volume or long-term functional outcomes was found.

Chasing the dragon--heroin-associated spongiform leukoencephalopathy.

A 21-year-old male presented with acute ataxia. For 1 week, he became increasingly unbalanced, clumsy, and severely dysarthric. He sustained multiple falls and had difficulty walking. He admitted to inhaling heated heroin vapors twice in the past, the last time was 1 week prior to admission. His symptoms started acutely 24 h after that. He denied injecting heroin in the past as he had a known “needle phobia”. On examination, his speech was severely dysarthric. He demonstrated horizontal nystagmus and positive cerebellar signs bilaterally with inability to stand without assistance and falling backwards when unsupported. Serum toxicology screen was negative. MRI revealed symmetrical white matter hyperintensities with a “C-shaped” lesion in the deep cerebellar hemispheres compatible with edema (Figs. 1 and 2). There was a loss of cerebellar folia, with inferior displacement of bilateral cerebral tonsils, compatible with developing cerebellar herniation through the foramen magnum (Fig. 2). Bilateral hypointensities involving the posterior limbs of the internal capsules were remarkable (Fig. 3).

Periprocedural Cost-Effectiveness Analysis of Mechanical Thrombectomy for Acute Ischemic Stroke in the Stent Retriever Era

Background: Early reperfusion is critical for favorable outcomes in acute ischemic stroke (AIS). Stent retrievers lead to faster and more complete reperfusion than previous technologies. Our aim is to compare the cost-effectiveness of stent retrievers to the previous mechanical thrombectomy devices. Methods: Retrospective review of endovascularly treated large-vessel AIS. Data from all consecutive patients who underwent thrombectomy from January 2012 through November 2012 were collected. Baseline characteristics, the total procedural cost, the rates of successful recanalization [modified thrombolysis in cerebral ischemia (mTICI) scores of 2b or 3], and the length of stay at the hospital were compared between the stent retriever (SR) and the non-stent retriever (NSR) groups. Results: After excluding the patients who underwent concomitant extracranial stenting (n = 22) or received intra-arterial tissue plasminogen activator only (n = 6), the entire cohort included 150 patients. The cost of the reperfusion procedure was significantly higher in the SR compared to the NSR group (USD 13,419 vs. 9,308, p <0.001). We were unable to demonstrate a statistically significant difference in the rates of mTICI 2b/3 reperfusion (81 vs. 74%, p = 0.337) or the length of stay (11.1 ± 9.1 vs. 12.8 ± 9.6 days, p = 0.260) amongst the SR and the NSR patients. Conclusion: The procedural costs of thrombectomy for AIS are increasing and account for the bulk of hospitalization reimbursement. The impact of these expenditures in the long-term sustainability of stroke centers deserves greater consideration. While it is likely that the SR technology results in higher rates of optimal reperfusion, better clinical outcomes, and shorter lengths of stay, larger studies are needed to prove its cost-effectiveness.

Clinical, angiographic and radiographic outcome differences among mechanical thrombectomy devices: initial experience of a large-volume center

Background and purpose Higher reperfusion rates have been established with endovascular treatment of acute ischemic stroke (AIS). There are limited data on the comparative performance of mechanical thrombectomy devices. Methods A retrospective single-center analysis was undertaken of all consecutive patients who underwent thrombectomy using Merci, Penumbra or stent retrievers (SR) from September 2010 to November 2012. Baseline characteristics, rates of successful recanalization (modified Thrombolysis in Cerebral Infarction (mTICI) score 2b–3), symptomatic intracerebral hemorrhage (sICH), final infarct volume, 90-day mortality and independent functional outcomes at 90 days were compared across the three devices. Results Our cohort included 287 patients. There were mild imbalances in baseline characteristics with trends towards higher National Institutes of Health Stroke Scale (NIHSS) score in patients in the Merci group (SR=18 vs Merci=21 vs Penumbra=19, p=0.06) and lower Alberta Stroke Program Early CT Score (ASPECTS) in patients in the SR group (>7: SR=51% vs Merci=61% vs Penumbra=62%, p=0.12). On univariate analysis there were no differences in the rate of sICH (SR=7% vs Merci=7% vs Penumbra=6%, p=0.921) and infarct volume (SR=61.5 mL vs Merci=69.5 mL vs Penumbra=59.2 mL, p=0.621). Trends towards better functional outcomes were found with Penumbra and SR vs Merci (41% vs 36% vs 25%, respectively, p=0.079). Complete or near complete reperfusion (mTICI 2b–3) was higher in the SR and Penumbra groups than in the Merci group (86% vs 78% vs 70%, respectively, p=0.027). Binary logistic regression showed that SR was an independent predictor of good functional outcome (OR 2.27, 95% CI 1.018 to 5.048; p=0.045). Conclusions Although our initial data confirm the superiority of SR technology over the Merci device, there was no significant difference in near complete/complete reperfusion, final infarct volumes or clinical outcomes between SR and Penumbra thromboaspiration.

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.