Embolectomy In Acute Ischemic Stroke Research Articles

Mechanical embolectomy for acute ischemic stroke beyond six hours from symptom onset using MRI based perfusion imaging

IntroductionThere is very limited data on the use of MRI based perfusion imaging to select patients with acute ischemic stroke and large vessel occlusion (LVO) for intraarterial therapy beyond 6h from onset. Our aim is to report the outcome of patients with acute ischemic stroke and large artery occlusion who presented beyond 6h from onset, had favorable MRI imaging profile, and underwent mechanical embolectomy. MethodsThis is a single institution (Rhode Island Hospital) retrospective study between December 1st, 2015, and July 30th, 2016 that included patients with acute ischemic stroke and proximal LVO with CT ASPECTS of 6 or more and 6–24h from symptom onset who were assessed for mechanical embolectomy using MRI based perfusion imaging. Favorable imaging profile was defined based on prior studies as 1) DWI lesion volume (as defined as apparent diffusion coefficient<620×10–6mm2/s) of 70ml or less; 2) Penumbra volume (as defined by volume of tissue with Tmax>6s) of 15ml or greater; 3) A mismatch ratio of 1.8 or more; and 4) Volume of tissue with perfusion lesion with Tmax>10s is <100ml. Good outcome was defined as a 90-day mRS≤2. Results41 patients met the inclusion criteria; 22 (53.7%) had favorable imaging profile and underwent mechanical embolectomy. The rate of good outcomes in this series was similar to that in a patient level pooled meta-analysis of the recent endovascular trials (63.6% vs. 46%, p=0.13). None of the patients in our cohort had symptomatic intracereberal hemorrhage. ConclusionsMRI perfusion based imaging may help select patients with acute ischemic stroke and proximal emergent LVO for embolectomy beyond the treatment window used in most endovascular trials. This provides compelling evidence for stroke centers to participate in ongoing trials using advanced imaging to study endovascular treatment in this patient population.

Abstract TP1: The Promising System to Support Rural Area Where No Intervenitionists to Perform Embolectomy for Acute Ischemic Stroke "Drive and Retrieve Method"

Introduction: In Japan, endovascular treatment for acute ischemic stroke from large vessel occlusion should be performed by neurointerventionists. However, most hospitals in rural area , that offer treatment for cerebral vascular disease do not have access to a neurointerventionist; the rural areas are especially affected. Thus, Our University has offered support to institutions without a neurointerventionist, to perform endovascular treatment. The neurointerventionists stationed in other hospitals drive to retrieve the resultant clot since the acute ischemic stroke from large vessel occlusion. We called this the “drive and retrieve system” method, and launched the prospective trial to evaluate the validity and efficacy of this method. Herein, we report the initial results of this trial. Methods: Nine institutes across our affiliated hospitals within a one-hour drive from Sapporo City took part in this trial. Three of these 9 institutes that have a full-time neurointerventionist were registered as the source. When an episode of acute ischemic stroke requiring intervention occurred in the other 6 hospitals, the available neurointerventionist provided treatment based on the drive and retrieve method. The neurointerventionists’ schedules was updated and distributed to all participating units twice a week, so that the supported hospitals could immediately make contact when required. We analysis the data of 44 cases in this trial from July 2015 to April 2016. Results: For 41 out of 44 cases (93%), Neurointerventionaists were able to respond immediately. The median time from door-to-puncture was 90 min (interquartile range [IQR]: 72-125). The median time from puncture to recanalization was also 76 min (IQR: 57.5-99.5). The recanalization rate (TICI 2b/3) was 77 %. mRS 0-2 was 39%. Conclusion: The drive and retrieve system has the potential to support rural medical institutes that do not have access to a full-time neurointerventionist.

Abstract WP39: Mechanical Embolectomy for Acute Ischemic Stroke Beyond Six Hours From Symptom Onset Using Advanced MR Imaging

Background: There is very limited data on the use of advanced neuroimaging to select patients with acute ischemic stroke and large vessel occlusion for intraarterial therapy beyond 6 hours from onset. Our aim is to report the outcome of patients with acute ischemic stroke and large artery occlusion who presented beyond 6 hours from onset, had favorable MRI imaging profile, and underwent mechanical embolectomy. Methods: This is a single institution retrospective study between December 1st, 2015, and July 30 th , 2016 with acute ischemic stroke and anterior circulation large vessel occlusion (LVO) with ASPECTS of 6 or more and beyond 6 hours from symptoms onset. Favorable imaging profile was defined as 1) DWI lesion volume (as defined as apparent diffusion coefficient &lt; 620 X 10-6 mm2/s) of 70 mL or less AND 2) Penumbra volume (as defined by volume of tissue with Tmax &gt;6 sec) of 15 mL or greater AND 3) A mismatch ratio of 1.8 or more AND 4) Volume of tissue with perfusion lesion with Tmax &gt; 10 sec is less than 100 mL. Good outcome was defined as a 90 day mRS≤2. Results: In the study period, 41 patients met the inclusion criteria; 22 (53.6%) had favorable imaging profile and underwent mechanical embolectomy. The median age was 75 years (59-92), 68.2% were females; the median time from last known normal to groin puncture was 684.5 minutes (range 363-1628) and the median admission NIHSS score was 17.5 (range 4-28). The rate of good outcomes in this series was similar to that in a patient level pooled meta-analysis of the recent endovascular trials (68.2% vs. 46.0%, p=0.07). The rate of good outcome matches that of the EXTEND-IA trial that selected patients using perfusion imaging (68.2% vs. 71.0%, p = 1.00). None of the patients in our cohort had symptomatic intracereberal hemorrhage. Conclusion: Advanced MR imaging may help select patients with acute ischemic stroke and anterior circulation large vessel occlusion for embolectomy beyond the treatment window used in most endovascular trials.

Regional availability of mechanical embolectomy for acute ischemic stroke in California, 2009 to 2010.

Background and Purpose—We sought to assess the geographic proximity of patients with stroke in California to centers that performed specific threshold volumes of mechanical embolectomy procedures each year.Methods—We identified all patients who were hospitalized for acute ischemic stroke at all nonfederal acute care hospitals in California from 2009 to 2010, and all hospitals that performed any mechanical embolectomy procedures by case volume during the same period, using nonpublic data from the Office of Statewide Health Planning and Development. We computed geographic service areas around each hospital on the basis of prespecified ground transport distance thresholds. We then calculated the proportion of hospitalized patients with stroke who lived within service areas for centers that performed a low volume and high volume of mechanical embolectomy procedures each year.Results—During the 2-year study period, 15% (53/360) of hospitals performed at least 1 mechanical embolectomy for acute stroke, but only 19% (10/53) performed >10 cases per year. Most hospitalized patients with stroke (94%) lived within a 2-hour transport time (65 miles) to a hospital that performed ≥1 procedure during the 2-year period. Approximately 93% of the patients with stroke who received mechanical embolectomy lived within 20 miles from an embolectomy-capable hospital compared with 7% of those who lived >20 miles.Conclusions—In California, most patients with stroke lived within reasonable ground transport distances from centers that performed ≥1 mechanical embolectomy in a 2-year period. The probability of receiving mechanical embolectomy for acute ischemic stroke was associated with living in close geographic proximity to these hospitals.

Mechanical embolectomy for acute ischemic stroke in the anterior cerebral circulation: the Gothenburg experience during 2000-2011.

Intra-arterial treatment of proximal occlusions in the cerebral circulation have become an important tool in the management of acute ischemic stroke. Our goal was to evaluate the safety and efficacy of intra-arterial acute ischemic stroke treatment performed in our institution in consecutive patients with anterior circulation occlusion during 2000-2011. We identified, in our data base, 156 consecutive cases with anterior acute ischemic stroke treated intra-arterially during 2000-2011. Stroke severity was defined according to the National Institutes of Health Stroke Scale, the results of the procedure were defined according to the modified Thrombolysis in Cerebral Infarction score, and clinical outcome was defined according to the modified Rankin scale, with favorable outcome ≤2 at 90 days. The mean admission NIHSS score was 19.4 (median, 20), with a mean time from stroke onset to groin puncture of 197 minutes (median, 171 minutes). The embolectomy tool of choice was the Amplatz GooseNeck snare (83%). Successful recanalization (modified TICI 2b +3) was seen in 74% of cases. A mRS ≤ 2 at 90 days was seen in 42% with a mortality rate of 17% and symptomatic intracerebral hemorrhage in 4%. A high recanalization rate was obtained with the Amplatz GooseNeck snare without any device-related complications. Favorable outcome, mortality, and symptomatic intracerebral hemorrhage are comparable with results of newer embolectomy devices.

Abstract TP390: Ethnic and Regional Disparities in Access to Endovascular Embolectomy for Acute Ischemic Stroke

Background: Endovascular stroke treatment volume has significantly increased in recent years. Data from the Nationwide Inpatient Sample (NIS) database in 2008 demonstrates an association between improved outcomes and centers that perform substantial procedural volume (&gt;10/year). Few reports have described demographics of patient populations or centers performing mechanical thrombectomy. Methods: We collected data from the 2008 NIS database for patients hospitalized for ischemic stroke, and those undergoing mechanical clot retrieval. Patients were characterized by ethnicity, payment source, and regional hospital variables of population density and median zipcode wealth. Patients were evaluated for admission and treatment at substantial thrombectomy volume centers. Results: Approximately 1.1 million patients were hospitalized for acute stroke, with 2749 patients receiving mechanical thrombectomy in 2008. Asian patients received the highest frequency of intervention (0.39%) with Blacks and Native Americans receiving the lowest (0.18%, 0.17%). Patients from zipcodes with highest median wealth most frequently received intervention (0.29%, p&lt;0.001). Among all stroke patients, Whites, Hispanics, individuals in highest salaried zip codes and patients residing in counties with population &gt; 1 million were most often admitted to centers with substantial endovascular procedural volume (all, p&lt;0.001 in multivariate analysis). Among those undergoing thrombectomy, Hispanics (p=0.03, OR 0.654 [0.442,0.967]), Asians (p=&lt;0.001, 0.205 [0.120,0.350]) and Blacks (p=0.09, OR 0.717[0.489,1.050]), were treated less frequently than Whites at substantial volume centers. Conclusion: Native Americans and Blacks received the lowest frequency of thrombectomy for acute ischemic stroke. Whites, individuals residing in wealthy and high population density regions were more often admitted to centers performing substantial procedural volume. Among patients undergoing mechanical thrombectomy, Whites were more often treated at substantial volume centers than Hispanics, Blacks or Asians. Though noted correlations may be multi-factorial, socioeconomic factors may predict admission and treatment in high volume procedural centers.

Abstract 71: Inpatient Complications, Outcomes and Predictors of Mortality in 80 Years or Older Patients Undergoing Mechanical Embolectomy for Acute Ischemic Stroke

Background and Purpose: Though utilization of mechanical embolectomy has increased in recent years, the procedure is still associated with significant morbidity and mortality in all age groups. We aimed to compare complications and outcomes after mechanical embolectomy between age groups ≥80 years and &lt;80 years and to identify the predictors of mortality among ≥80 years. Methods: We identified patients with acute ischemic stroke who underwent mechanical embolectomy in 2006-2009 from Nationwide Inpatient Sample (NIS) of Healthcare Cost and Utilization Project (HCUP). We compared co-morbidities and inpatient complications between age ≥80 and &lt;80 years after sample weighting to get estimates of population. Multivariate logistic regression model was constructed to identify predictors of inpatient mortality in age ≥80 years. Results: Of the 6723 adults who underwent mechanical embolectomy, 1298 (19%) were ≥80 years. Compared to younger, octogenerians were more likely (p&lt;0.05) to be of female gender (68% vs. 46%) and white race (83% vs. 74%). They also had higher Elixhauser co-morbidity index (mean ± SD: 3.4 ± 1.6 vs. 3.0 ± 1.7). Unadjusted mortality rate was higher (31% vs. 22%) and rate of functional independence at discharge was lower (4% vs. 16%) for age ≥80 years. Age ≥80 years had significantly higher incidence of acute myocardial infarction (7% vs. 5%), acute kidney injury (9% vs. 6%), GI bleeding (3% vs. 2%), need for blood products transfusion (10% vs. 8%), and urinary infections (22% vs. 15%). Use of concomitant thrombolytic treatment (intravenous or intra-arterial) was higher (58% vs. 53%) in age ≥80 years. Incidence of intracranial hemorrhage (11% vs. 10%) was similar (p&gt;0.05) between the two cohorts, as were the rates of mechanical ventilation (29% vs. 30%), gastrostomy tube placement (17% vs. 15%) and permanent tracheostomy (0.8% vs. 0.7%). After adjusting for gender, race, inter-facility transfer status, and length of hospitalization, significant predictors of in-hospital mortality for age ≥80 years were intracranial hemorrhage, sepsis, mechanical ventilation, acute myocardial infarction, acute kidney injury, and chronic pulmonary disease. Use of thrombolytic treatment did not change inpatient mortality ( Table ). Conclusions: Morbidity and mortality in mechanical embolectomy for ischemic stroke in age ≥80 years are significantly higher compared with younger. Inpatient medical complications independently predict mortality in age ≥80 years.

104: TIMI Flow Obtained After Mechanical Embolectomy for Acute Ischemic Stroke and Its Impact on Functional Outcome

104: TIMI Flow Obtained After Mechanical Embolectomy for Acute Ischemic Stroke and Its Impact on Functional Outcome

Safety and Efficacy of Mechanical Embolectomy in Acute Ischemic Stroke: Results of the MERCI Trial

Safety and Efficacy of Mechanical Embolectomy in Acute Ischemic Stroke: Results of the MERCI Trial

Safety and Efficacy of Mechanical Embolectomy in Acute Ischemic Stroke

The only Food and Drug Administration (FDA)-approved treatment for acute ischemic stroke is tissue plasminogen activator (tPA) given intravenously within 3 hours of symptom onset. An alternative strategy for opening intracranial vessels during stroke is mechanical embolectomy, especially for patients ineligible for intravenous tPA. We investigated the safety and efficacy of a novel embolectomy device (Merci Retriever) to open occluded intracranial large vessels within 8 hours of the onset of stroke symptoms in a prospective, nonrandomized, multicenter trial. All patients were ineligible for intravenous tPA. Primary outcomes were recanalization and safety, and secondary outcomes were neurological outcome at 90 days in recanalized versus nonrecanalized patients. Recanalization was achieved in 46% (69/151) of patients on intention to treat analysis, and in 48% (68/141) of patients in whom the device was deployed. This rate is significantly higher than that expected using an historical control of 18% (P<0.0001). Clinically significant procedural complications occurred in 10 of 141 (7.1%) patients. Symptomatic intracranial hemorrhages was observed in 11 of 141 (7.8%) patients. Good neurological outcomes (modified Rankin score < or =2) were more frequent at 90 days in patients with successful recanalization compared with patients with unsuccessful recanalization (46% versus 10%; relative risk [RR], 4.4; 95% CI, 2.1 to 9.3; P<0.0001), and mortality was less (32% versus 54%; RR, 0.59; 95% CI, 0.39 to 0.89; P=0.01). A novel endovascular embolectomy device can significantly restore vascular patency during acute ischemic stroke within 8 hours of stroke symptom onset and provides an alternative intervention for patients who are otherwise ineligible for thrombolytics.