Randall C. Edgell

Hospital Mortality and Complications of Electively Clipped or Coiled Unruptured Intracranial Aneurysm

Background and Purpose— To determine the hospital mortality rates associated with elective surgical clipping and endovascular coiling of unruptured intracranial aneurysms. Methods— We identified a cohort of patients electively admitted to US hospitals with the diagnosis of unruptured intracranial aneurysm from the National Inpatient Sample database for the years 2000 through 2006. Patient demographics, hospital-associated complications, and in-hospital mortality were compared among the treatment groups. A multivariate logistic regression analysis was used to identify independent variables associated with hospital mortality. Cochrane–Armitage test was used to assess the trend of hospital use of these procedures. Results— After data cleansing, 3738 (34.3%) patients had aneurysm clipping and 3498 (32.1%) had endovascular coiling. The basic demographics including age, race, and comorbidity indices were similar between the groups. The length of hospital stay was longer in the clipped population (median 4 versus 1 day; P<0.0001), incurring a higher hospital charge in the coiled population (median

Mortality of Cerebral Venous–Sinus Thrombosis in a Large National Sample

42 070 versus

Is Thrombolysis Safe in the Elderly? Analysis of a National Database

38 166; P<0.0001). Hospital mortality was higher in the clipped population: 60 (1.6%) versus 20 (0.57%; adjusted odds ratio 3.63; 95% CI, 1.57, 8.42). Perioperative intracerebral hemorrhage and acute ischemic stroke were higher in the clipped population. The rate of hospital use of the endovascular coiling has increased over the years included in this study (<0.0001). Conclusions— Elective coiling of unruptured intracranial aneurysms is associated with fewer deaths and perioperative complications compared with elective clipping. The trend of hospital use of the coiling procedures has increased during recent years.

Demand-supply of neurointerventionalists for endovascular ischemic stroke therapy

Background and Purpose— The purpose of this study was to evaluate the mortality rates associated with cerebral venous–sinus thrombosis in a large national sample. Methods— A cohort of patients with cerebral venous–sinus thrombosis was identified from the National Inpatient Sample database for the years 2000 to 2007. According to the International Classification of Diseases, 9th Revision, Clinical Modification codes, cerebral venous–sinus thrombosis is categorized into pyogenic and nonpyogenic groups. Multivariate logistic regression analysis was used to assess covariates associated with hospital mortality. Results— Among 3488 patients, the overall mortality rate was 4.39%, which was nonsignificantly higher among the pyogenic group (4.55% versus 3.52%; OR, 0.76; 95% CI, 0.47–1.23). In the pyogenic cerebral venous–sinus thrombosis group, hematologic disorders were the most frequent predisposing condition (16.2%); whereas systemic malignancy followed by hematologic disorders were most common in the nonpyogenic group (14.08% and 10.04%, respectively). Predictors of mortality included age, intracerebral hemorrhage as well as the predisposing conditions of hematologic disorders, systemic malignancy, and central nervous system infection. Conclusions— Compared with arterial stroke, CVST harbors a relatively low mortality rate. Death is determined by age, the presence of intracerebral hemorrhage, and certain predisposing conditions.

Endovascular therapy for acute ischemic stroke with occlusion of the middle cerebral artery M2 segment

Background and Purpose— Thrombolysis for acute ischemic stroke in the elderly population is seldom administered. Methods— In this study, we evaluated the risks of thrombolysis, including the mortality and intracerebral hemorrhage (ICH) rates in this population. A cohort of patients was identified from the National Inpatient Sample database for the years 2000–2006. Age was categorized in 2 groups, including those between 18 and 80 years and those >80 years. Multivariate logistic regression analysis was used to assess covariates associated with hospital mortality and ICH. A total of 524 997 patients were admitted for acute ischemic stroke; 143 093 (27.2%) were >80 years. A total of 7950 patients were treated with thrombolysis, of which 1659 (20.9%) were >80 years. Elderly patients received less frequent thrombolysis compared with the younger population (1.05% versus 1.72%). Results— In the whole cohort, the mortality rate was higher in the older population (12.80% versus 8.99%). For those treated with thrombolysis, the mortality rate and risk of ICH were higher among those >80 years (16.9% versus 11.5%; odds ratio: 1.56 [95% CI: 1.35 to 1.82] and 5.73% versus 4.40%; odds ratio: 1.31 [95% CI: 1.03 to 1.67], respectively). Multivariate logistic regression analysis showed that the presence of ICH (odds ratio: 2.24 [95% CI: 1.89 to 2.65]) was associated with higher mortality rates but not the use of thrombolysis (odds ratio: 1.14 [95% CI: 0.98 to 1.33]). Conclusions— Despite the higher mortality rate in the older population, the use of thrombolysis does not predict death; however, the use of thrombolysis was associated with high risk of ICH.

Optimizing Prediction Scores for Poor Outcome After Intra-Arterial Therapy in Anterior Circulation Acute Ischemic Stroke

Objective: To estimate the needed workforce of trained neurointerventionalists (NIs) to perform endovascular therapy (ET) for eligible patients with acute ischemic stroke (AIS). Method: Population and ischemic stroke incidence data were extracted with use of US Census and Centers for Disease Control and Prevention 2009 estimates. The annual “demand” is defined as the proportion of AIS patients who would meet inclusion criteria and clinical standards for ET. The “supply” is defined as the number of trained NIs and NIs in training. The “workforce” is the number of NIs needed to meet the demand (the number of eligible AIS patients) within an accessible geographic diameter. Data on NIs and NI fellowships were collected (Society of Neurointerventional Surgery [SNIS], Society of Vascular & Interventional Neurology [SVIN], Concentric Medical, and Penumbra Inc.). Results: The estimated number of NIs is close to 800, practicing within a 50-mile radius of major metropolitan areas in the United States, covering more than 95% of the US population. Approximately 40 NI fellows are graduating yearly from US training programs. In 5 years and 10 years, the number of NIs may reach 1,000 and 1,200, respectively. Currently, there are approximately 14,000 thrombectomy procedures performed in the United States each year. However, the percentage of AIS patients who may be eligible for ET in our estimation is 4% to 14%, or about 25,000 to 95,000 patients. This means that cases will occur at a rate of 26 to 97 per year in 5 years, or 22 to 81 per year in 10 years, for each NI. Providing 24/7 AIS coverage requires 2 to 3 NIs per medical center, adding to the challenge of providing manpower without diluting experience in areas of lower population density. Conclusion: The current and projected number of NIs would adequately supply the future need if the proportion of patients requiring AIS endovascular therapy increases. However, 2 to 3 NIs per comprehensive stroke center would be needed to provide 24/7 AIS therapy with a sufficient number of cases per NI. A tertiary stroke center model similar to the trauma model may provide the manpower solution without compromising the quality of care.

Revascularization grading in endovascular acute ischemic stroke therapy

Importance Randomized clinical trials have shown the superiority of endovascular therapy (EVT) compared with best medical management for acute ischemic strokes with large vessel occlusion (LVO) in the anterior circulation. However, of 1287 patients enrolled in 5 trials, 94 with isolated second (M2) segment occlusions were randomized and 51 of these received EVT, thereby limiting evidence for treating isolated M2 segment occlusions as reflected in American Heart Association guidelines. Objective To evaluate EVT safety and effectiveness in M2 occlusions in a cohort of patients with acute ischemic stroke. Design, Setting, and Participants This multicenter retrospective cohort study pooled patients with acute ischemic strokes and LVO isolated to M2 segments from 10 US centers. Patients with acute ischemic strokes and LVO in M2 segments presenting within 8 hours from their last known normal clinical status (LKN) from January 1, 2012, to April 30, 2015, were divided based on their treatment into EVT and medical management groups. Logistic regression was used to compare the 2 groups. Univariate and multivariate analyses evaluated associations with good outcome in the EVT group. Main Outcomes and Measures The primary outcome was the 90-day modified Rankin Scale score (range, 0-6; scores of 0-2 indicate a good outcome); the secondary outcome was symptomatic intracerebral hemorrhage. Results A total of 522 patients (256 men [49%]; 266 women [51%]; mean [SD] age, 68 [14.3] years) were identified, of whom 288 received EVT and 234 received best medical management. Patients in the medical management group were older (median [interquartile range] age, 73 [60-81] vs 68 [56-78] years) and had higher rates of intravenous tissue plasminogen activator treatment (174 [74.4%] vs 172 [59.7%]); otherwise the 2 groups were balanced. The rate of good outcomes was higher for EVT (181 [62.8%]) than for medical management (83 [35.4%]). The EVT group had 3 times the odds of a good outcome as the medical management group (odds ratio [OR], 3.1; 95% CI, 2.1-4.4; P < .001) even after adjustment for age, National Institute of Health Stroke Scale (NIHSS) score, Alberta Stroke Program Early Computed Tomographic Score (ASPECTS), intravenous tissue plasminogen activator treatment, and time from LKN to arrival in the emergency department (OR, 3.2; 95% CI, 2-5.2; P < .001). No statistical difference in symptomatic intracerebral hemorrhage was found (5.6% vs 2.1% for the EVT group vs the medical management group; P = .10). The treatment effect did not change after adjusting for center (OR, 3.3; 95% CI, 1.9-5.8; P < .001). Age, NIHSS score, ASPECTS, time from LKN to reperfusion, and successful reperfusion score of at least 2b (range, 0 [no perfusion] to 3 [full perfusion with filling of all distal branches]) were independently associated with good outcome of EVT. A linear association was found between good outcome and time from LKN to reperfusion. Conclusions and Relevance Although a randomized clinical trial is needed to confirm these findings, available data suggest that EVT is reasonable, safe, and effective for LVO of the M2 segment relative to best medical management.

Mechanical Thrombectomy for Cerebral Venous Sinus Thrombosis: A Comprehensive Literature Review

Background and Purpose— Intra-arterial therapy (IAT) promotes recanalization of large artery occlusions in acute ischemic stroke. Despite high recanalization rates, poor clinical outcomes are common. We attempted to optimize a score that combines clinical and imaging variables to more accurately predict poor outcome after IAT in anterior circulation occlusions. Methods— Patients with acute ischemic stroke undergoing IAT at University of Texas (UT) Houston for large artery occlusions (middle cerebral artery or internal carotid artery) were reviewed. Independent predictors of poor outcome (modified Rankin Scale, 4–6) were studied. External validation was performed on IAT-treated patients at Emory University. Results— A total of 163 patients were identified at UT Houston. Independent predictors of poor outcome (P⩽0.2) were identified as score variables using sensitivity analysis and logistic regression. Houston Intra-Arterial Therapy 2 (HIAT2) score ranges 0 to 10: age (⩽59=0, 60–79=2, ≥80 years=4), glucose (<150=0, ≥150=1), National Institute Health Stroke Scale (⩽10=0, 11–20=1, ≥21=2), the Alberta Stroke Program Early CT Score (8–10=0, ⩽7=3). Patients with HIAT2≥5 were more likely to have poor outcomes at discharge (odds ratio, 6.43; 95% confidence interval, 2.75–15.02; P<0.001). After adjusting for reperfusion (Thrombolysis in Cerebral Infarction score ≥2b) and time from symptom onset to recanalization, HIAT2≥5 remained an independent predictor of poor outcome (odds ratio, 5.88; 95% confidence interval, 1.96–17.64; P=0.02). Results from the cohort of Emory (198 patients) were consistent; patients with HIAT2 score ≥5 had 6× greater odds of poor outcome at discharge and at 90 days. HIAT2 outperformed other previously published predictive scores. Conclusions— The HIAT2 score, which combines clinical and imaging variables, performed better than all previous scores in predicting poor outcome after IAT for anterior circulation large artery occlusions.

Does dementia increase risk of thrombolysis? A case-control study

Background: Recanalization and angiographic reperfusion are key elements to successful endovascular and interventional acute ischemic stroke (AIS) therapy. Intravenous recombinant tissue plasminogen activator (rt-PA), the only established revascularization therapy approved by the US Food & Drug Administration for AIS, may be less effective for large artery occlusion. Thus, there is enthusiasm for endovascular revascularization therapies, which likely provide higher recanalization rates, and trials are ongoing to determine clinical efficacy and compare various methods. It is anticipated that clinical efficacy will be well correlated with revascularization of viable tissue in a timely manner. Method: Reporting, interpretation, and comparison of the various revascularization grading methods require agreement on measurement criteria, reproducibility, ease of use, and correlation with clinical outcome. These parameters were reviewed by performing a Medline literature search from 1965 to 2011. This review critically evaluates current revascularization grading systems. Results and Conclusion: The most commonly used revascularization grading methods in AIS interventional therapy trials are the thrombolysis in cerebral ischemia (TICI, pronounced “tissy”) and thrombolysis in myocardial ischemia (TIMI) scores. Until further technical and imaging advances can incorporate real-time reliable perfusion studies in the angio-suite to delineate regional perfusion more accurately, the TICI grading system is the best defined and most widely used scheme. Other grading systems may be used for research and correlation purposes. A new scale that combines primary site occlusion, lesion location, and perfusion should be explored in the future.

Age-Associated Vasospasm in Aneurysmal Subarachnoid Hemorrhage

Background: Endovascular treatment of cerebral venous sinus thrombosis (CVST) includes pharmacological and mechanical thrombolysis. Methods: The authors searched the English literature on CVST from 1990 to 2012 for all case reports or case series of mechanical thrombectomy. Results: A total of 64 patients were treated in all published studies. The techniques for mechanical thrombectomy included rheolytic thrombectomy with an AngioJet device (46.9%), clot retraction with the Penumbra system (4.7%), clot retraction with a Fogarty catheter (1.6%), clot retraction with a microsnare (3.1%), balloon venoplasty without stenting (18.7%), balloon venoplasty with stenting (4.7%), and an amalgam of techniques (18.7%). Nine (16.1%) patients died. At the most recent follow-up, 40 (62.5%) patients had no disability or minor disability and 7 (10.9%) patients had major disability. Conclusion: Randomized multiinstitutional clinical trials with larger number of participants are needed to sufficiently compare the effect of intrasinus thrombolysis and mechanical thrombectomy to standard-of-care anticoagulation therapy.