Maxim Hammer

Emergent Stenting of Extracranial Internal Carotid Artery Occlusion in Acute Stroke Has a High Revascularization Rate

Background and Purpose— Acute ischemic stroke attributable to extracranial internal carotid artery (ICA) occlusion is frequently associated with severe disability or death. In selected cases, revascularization with carotid artery stenting has been reported, but the safety, recanalization rate, and clinical outcomes in consecutive case series are not known. Methods— We retrospectively reviewed all of the cases of ICA occlusions that underwent cerebral angiography with the intent to revascularize over a 38-month period. Two groups were identified: (1) patients who presented with an acute clinical presentation within 6 hours of symptom onset (n=15); and (2) patients who presented subacutely with neurologic fluctuations because of the ICA occlusion (n=10). Results— Twenty-five patients with a mean age of 62±11 years and median National Institutes of Health Stroke Scale (NIHSS) of 14 were identified. Twenty-three of the 25 patients (92%) were successfully revascularized with carotid artery stenting. Patients in group 1 were younger and more likely to have a tandem occlusion and higher baseline NIHSS when compared with group 2. Patients in group 2 were more likely to show early clinical improvement defined as a reduction of their NIHSS by ≥4 points and a modified Rankin Score of ≤2 at 30-day follow-up. Two clinically insignificant adverse events were noted: 1 asymptomatic hemorrhage and 1 nonflow-limiting dissection. Conclusions— Endovascular treatment of acute ICA occlusion appears to have a high-recanalization rate and be relatively safe in our cohort of patients with acute ICA occlusion. Future prospective studies are necessary to determine which patients are most likely to benefit from this form of therapy.

Safety, Feasibility, and Short-Term Follow-Up of Drug-Eluting Stent Placement in the Intracranial and Extracranial Circulation

Background and Purpose— The use of bare metal stents to treat symptomatic intracranial stenosis may be associated with significant restenosis rates. The advent of drug-eluting stents (DESs) in the coronary circulation has resulted in a reduction of restenosis rates. We report our technical success rate and short-term restenosis rates after stenting with DESs in the intracranial and extracranial circulation. Methods— This study was a retrospective review of the period between April 1, 2004, and April 15, 2006, of 59 patients with 62 symptomatic intracranial or extracranial atherosclerotic lesions at 2 medical centers (University of Pittsburgh and Borgess Medical Center). Results— The mean age of our cohort was 61±12 years. The location of the 62 lesions was as follows: extracranial vertebral artery 31 (50%), intracranial vertebral artery or basilar artery 18 (29%), extracranial internal carotid artery (ICA) near the petrous bone 5 (8%), and intracranial ICA 8 (13%). There were 2 (3%) periprocedural complications: 1 non—flow-limiting dissection and 1 disabling stroke. Fifty vessels were available for follow-up angiography or computed tomography angiography at a median time of 4.0±2 months. A total of 2 of 36 extracranial stents (7%) and 1 of 26 intracranial stents (5%) were found to have restenosis ≥50% at follow-up. Conclusions— This report demonstrates that DES delivery in the intracranial and extracranial circulation is technically feasible. A small percentage of patients developed short-term in-stent restenosis. Longer-term follow-up is required in the setting of a prospective study to determine the late restenosis rates for DESs in comparison with bare metal stents.

Comparison of Safety and Clinical and Radiographic Outcomes in Endovascular Acute Stroke Therapy for Proximal Middle Cerebral Artery Occlusion With Intubation and General Anesthesia Versus the Nonintubated State

Background and Purpose— There is considerable heterogeneity in practice patterns between sedation in the intubated state vs nonintubated state during endovascular acute stroke therapy. We sought to compare clinical and radiographic outcomes between these 2 sedation modalities. Methods— Consecutive patients with acute stroke due to middle cerebral artery–M1 segment occlusion treated with endovascular therapy between January 2006 and July 2009 were identified in our interventional acute stroke database. Level of sedation was determined as intubated (IS) vs nonintubated (NIS) state. Final infarct volumes on follow-up imaging and clinical outcomes at 3 to 6 months were obtained. Results— A total of 126 patients were included (73 [58%] NIS vs 53 [42%] IS). In IS patients, intensive care unit length of stay was longer (6.5 vs 3.2 days, P=0.0008). Intraprocedural complications were lower in NIS patients compared with IS patients (5/73 [6%] vs 8/53 [15%], respectively), but the difference was not significant (P=0.13). In univariate and multivariate analyses, NIS was significantly associated with in-hospital mortality (odds ratio=0.32, P=0.011), good clinical outcome (odds ratio=3.06, P=0.042), and final infarct volume (odds ratio=0.25, P=0.004). Conclusion— In endovascular acute stroke therapy, treatment of patients in NIS appears to be as safe as treatment in IS and may result in more favorable clinical and radiographic outcomes. Our preliminary observations derived from this retrospective study await confirmation from prospective trials.

Multimodal Reperfusion Therapy for Acute Ischemic Stroke: Factors Predicting Vessel Recanalization

Background and Purpose— Endovascular therapies using mechanical and pharmacological modalities for large vessel occlusions in acute stroke are rapidly evolving. Our aim was to determine whether one modality is associated with higher recanalization rates. Methods— We retrospectively reviewed 168 consecutive patients treated with intra-arterial (IA) therapy for acute ischemic stroke between May 1999 and November 15, 2005. Demographic, clinical, radiographic, angiographic, and procedural notes were reviewed. Recanalization was defined as achieving thrombolysis in myocardial infarction 2 or 3 flow after intervention. A logistic regression model was constructed to determine independent predictors of successful recanalization. Results— A total of 168 patients were reviewed with a mean age of 64±13 years and mean National Institutes of Health Stroke Scale score of 17±4. Recanalization was achieved in 106 (63%) patients. Independent predictors of recanalization include: the combination of IA thrombolytics and glycoprotein IIb/IIIa inhibitors (odds ratio [OR], 2.9 [95% CI, 1.04 to 6.7]; P<0.048), intracranial stent placement with angioplasty (OR, 4.8 [95% CI, 1.8 to 10.0]; P<0.001), or extracranial stent placement with angioplasty (OR, 4.2 [95% CI, 1.4 to 9.8]; P<0.014). Lesions at the terminus of the internal carotid artery were recalcitrant to revascularization (OR, 0.34 [95% CI, 0.16 to 0.73]; P value 0.006). Conclusions— Intracranial or extracranial stenting or combination therapy with IA thrombolytics and glycoprotein IIb/IIIa inhibitors in the setting of multimodal therapy is associated with successful recanalization in patients treated with multimodal endovascular reperfusion therapy for acute ischemic stroke.

Endovascular Treatment of Tandem Extracranial/Intracranial Anterior Circulation Occlusions Preliminary Single-Center Experience

Background and Purpose— Acute ischemic stroke due to tandem occlusions of the extracranial internal carotid artery and intracranial arteries has a poor natural history. We aimed to evaluate our single-center experience with endovascular treatment of this unique stroke population. Methods— Consecutive patients with tandem occlusions of the internal carotid artery origin and an intracranial artery (ie, internal carotid artery terminus, M1 middle cerebral artery, or M2 middle cerebral artery) were studied retrospectively. Treatment consisted of proximal revascularization with angioplasty and stenting followed by intracranial intervention. Endpoints were recanalization of both extracranial and intracranial vessels (Thrombolysis In Myocardial Ischemia ≥2), parenchymal hematoma, and good clinical outcome (modified Rankin Scale ⩽2) at 3 months. Results— We identified 77 patients with tandem occlusions. Recanalization occurred in 58 cases (75.3%) and parenchymal hematoma occurred in 8 cases (10.4%). Distal embolization occurred in 3 cases (3.9%). In 18 of 77 patients (23.4%), distal (ie, intracranial) recanalization was observed after proximal recanalization, obviating the need for distal intervention. Good clinical outcomes were achieved in 32 patients (41.6%). In multivariate analysis, Thrombolysis In Myocardial Ischemia ≥2 recanalization, baseline National Institutes of Health Stroke Scale score, baseline Alberta Stroke Programme Early CT score, and age were significantly associated with good outcome. Conclusions— Endovascular therapy of tandem occlusions using extracranial internal carotid artery revascularization as the first step is technically feasible, has a high recanalization rate, and results in an acceptable rate of good clinical outcome. Future randomized, prospective studies should clarify the role of this approach.

Final Infarct Volume Is a Stronger Predictor of Outcome Than Recanalization in Patients With Proximal Middle Cerebral Artery Occlusion Treated With Endovascular Therapy

Background and Purpose— The rationale for recanalization therapy in acute ischemic stroke is to preserve brain through penumbral salvage and thus improve clinical outcomes. We sought to determine the relationship between recanalization, clinical outcomes, and final infarct volumes in acute ischemic stroke patients presenting with middle cerebral artery occlusion who underwent endovascular therapy and post-procedure magnetic resonance imaging. Methods— We identified 201 patients with middle cerebral artery occlusion. Patients with other occlusive lesions were excluded. Baseline clinical/radiological characteristics, procedural outcomes (including thrombolysis in cerebral infarction scores), clinical outcome scores (modified Rankin scores), and final infarct volumes on diffusion weighted imaging were retrospectively analyzed from a prospectively collected database. Favorable outcome is defined as 90-day modified Rankin score ⩽2. Results— Successful recanalization (thrombolysis in cerebral infarction grade 2b or 3) was achieved in 63.2% and favorable outcomes in 46% of cases. Mean infarct volume was 50.1 mL in recanalized versus 133.9 mL in non-recanalized patients (P<0.01) and 40.4 mL in patients with favorable outcomes versus 111.8 in patients with unfavorable outcomes (P<0.01). In multivariate analysis, thrombolysis in cerebral infarction ≥2b, baseline National Institute of Health Stroke Scale, Alberta Stroke Program Early Computed Tomography scores, and age were identified as independent predictors of outcome. However, when infarct volumes were included in the analysis only final infarct volume and age remained significantly associated. Conclusions— Successful recanalization leads to improved functional outcomes through a reduction in final infarct volumes. In our series, age and final infarct volume but not recanalization were found to be independent predictors of outcome, supporting the use of final infarct volume as surrogate marker of outcome in acute stroke trials.

Mechanical Approaches Combined With Intra-Arterial Pharmacological Therapy Are Associated With Higher Recanalization Rates Than Either Intervention Alone in Revascularization of Acute Carotid Terminus Occlusion

Background and Purpose— Acute stroke attributable to internal carotid artery terminus occlusion carries a poor prognosis. Vessel recanalization is crucial to improve clinical outcome. Historically, pharmacological thrombolysis alone has low recanalization rates. We sought to determine whether adjunctive mechanical approaches achieve better vessel recanalization and functional outcome. Methods— We retrospectively reviewed 75 consecutive endovascular cases of acute internal carotid artery terminus occlusions treated at our center between 1998 and 2008. Mechanical approaches (MERCI retrieval/angioplasty/stent) with and without adjunctive intra-arterial pharmacological therapy (urokinase or tissue plasminogen activator) was compared to intra-arterial lytics alone. Univariate and multivariate analyses were performed to determine predictors of recanalization (thrombolysis in myocardial infarction grades 2 to 3) and favorable functional outcome (modified Rankin score ≤2) at 3 months. Results— Lowest recanalization rates were observed with intra-arterial lytics alone (3/17, 17.6%). MERCI embolectomy combined with intra-arterial lytics was associated with the highest recanalization rates (18/21, 85.7%; P<0.0001). MERCI embolectomy alone achieved 46.2% recanalization rates (6/13; P=0.23). Angioplasty or stenting and intra-arterial lytics achieved 25% (2/8; P=0.65) and 40% (4/10; P=0.085) recanalization, respectively. In multivariate analysis, combination of MERCI embolectomy with intra-arterial lytics (OR, 16.2; CI, 4.6–77.6), or any mechanical technique with intra-arterial lytics (OR, 6.7; CI, 2.5–19.5) independently predicted thrombolysis in myocardial infarction 2 to 3 recanalization. Clinically significant parenchymal hemorrhage rates were 7.5% with combination (3/38) and 12.5% with pharmacological therapies (2/16; P=0.46). Using stepwise logistic regression, age (OR, 0.95; CI, 0.90–0.995), baseline NIHSS (OR, 0.82; CI, 0.70–0.96), and thrombolysis in myocardial infarction 2 to 3 recanalization (OR, 4.0; CI, 1.1–14.4) were associated with favorable functional outcome. Conclusions— Combined mechanical and intra-arterial pharmacological therapy is associated with higher recanalization rates than either intervention alone in acute internal carotid artery terminus occlusion revascularization.

Partial Aortic Occlusion for Cerebral Perfusion Augmentation Safety and Efficacy of NeuroFlo in Acute Ischemic Stroke Trial

Background and Purpose— Fewer than 5% of patients with acute ischemic stroke are currently treated, and there is need for additional treatment options. A novel catheter treatment (NeuroFlo) that increases cerebral blood flow was tested to 14 hours. Methods— The Safety and Efficacy of NeuroFlo in Acute Ischemic Stroke trial is a randomized trial of the safety and efficacy of NeuroFlo treatment in improving neurological outcome versus standard medical management. The primary safety end point was the incidence of serious adverse events through 90 days. The primary efficacy end point on a modified intent-to-treat population was a global disability end point at 90 days. Secondary end points included mortality, intracranial hemorrhage, modified Rankin scale score outcome of 0 to 2, and modified Rankin scale shift analysis. Results— Between October 2005 and January 2010, 515 patients were enrolled at 68 centers in 9 countries. The primary efficacy end point did not reach statistical significance (OR, 1.17; CI, 0.81–1.67; P=0.407). The primary safety end point did not show a difference in serious adverse events (P=0.923). Ninety-day mortality was 11.3% (26/230) in treatment and 16.3% (42/257) in control (P=0.087). Post hoc analyses showed that patients presenting within 5 hours (OR, 3.33; CI, 1.31–8.48), with NIHSS score 8 to 14 (OR, 1.80; CI, 0.99–3.30), or older than age 70 years (OR, 2.02; CI, 1.02–4.03) had better modified Rankin scale score outcomes of 0 to 2; additionally, there were fewer stroke-related deaths in treatment compared to control groups (7.4%=17/230; 14.4%=37/257). Conclusions— The trial met its primary safety end point but not its primary efficacy end point. Signals of treatment effect were suggested on all-cause mortality, in patients presenting early, older than age 70 years, or with moderate strokes, but these require confirmation. Clinical Trial Registration Information— URL: http://clinicaltrials.gov. Unique identifier: NCT00119717.

Factors Predicting Hemorrhagic Complications after Multimodal Reperfusion Therapy for Acute Ischemic Stroke

BACKGROUND AND PURPOSE: We sought to find predictors for hemorrhagic complications in patients with acute ischemic stroke treated with multimodal endovascular therapy. MATERIALS AND METHODS: We retrospectively reviewed patients with acute ischemic stroke treated with multimodal endovascular therapy from May 1999 to March 2006. We reviewed clinical and angiographic data, admission CT Alberta Stroke Programme Early CT Score (ASPECTS), and the therapeutic endovascular interventions used. Posttreatment CT scans were reviewed for the presence of a parenchymal hematoma or hemorrhagic infarction based on defined criteria. Predictors for these types of hemorrhages were determined by logistic regression analysis. RESULTS: We identified 185 patients with a mean age of 65 ± 13 years and mean National Institutes of Health Stroke Scale score of 17 ± 4. Sixty-nine patients (37%) developed postprocedural hemorrhages: 24 (13%) parenchymal hematomas and 45 (24%) hemorrhagic infarctions. Patients with tandem occlusions (odds ratio [OR] 4.6 [1.4–6.5], P < .016), hyperglycemia (OR 2.8 [1.1–7.7], P < .043), or treated concomitantly with intravenous (IV) tissue plasminogen activator (tPA) and intra-arterial (IA) urokinase (OR 5.1 [1.1–25.0], P < .041) were at a significant risk for a parenchymal hematoma. Hemorrhagic infarction occurred significantly more in patients presenting with an ASPECTS ≤7 (OR 1.9 [1.3–2.7], P < .01). CONCLUSIONS: Hemorrhagic infarctions are related to the extent of infarct based on presentation CT, whereas parenchymal hematomas are associated with the presence of tandem occlusions, hyperglycemia, and treatment with both IV tPA and IA urokinase in patients with acute stroke treated with multimodal endovascular therapy.

Telestroke-Guided Intravenous Tissue-Type Plasminogen Activator Treatment Achieves a Similar Clinical Outcome as Thrombolysis at a Comprehensive Stroke Center

Background and Purpose— Telestroke networks offer an opportunity to increase tissue-type plasminogen activator use in community hospitals. Methods— We compared 83 patients treated with intravenous tissue-type plasminogen activator by telestroke to 59 patients treated after in-person evaluation by the same neurologists at a tertiary care stroke center. Onset and door-to-treatment times and functional outcome at 90 days were obtained prospectively. Favorable outcome was defined as modified Rankin Scale score ⩽2. Results— Favorable outcome rates were comparable between the groups (42.1% versus 37.5%, P=0.7). There was no significant difference in the rate of symptomatic hemorrhage. Conclusions— Telestroke is a viable alternative to in-person evaluation when stroke expertise is not readily available.