Stent Retriever Devices Research Articles

Rapid learning curve for Solitaire FR stent retriever therapy: evidence from roll-in and randomised patients in the SWIFT trial

BackgroundIn light of recent positive trial data for endovascular therapy in acute ischemic stroke (AIS), stent retriever use by practitioners without prior experience with these devices may become more common.ObjectiveTo...

Abstract T MP9: Primary Thrombectomy Within 3 Hours Of Onset In Acute Ischemic Stroke From Occlusion Of Middle Cerebral Artery- A Pilot Study

Background: Acute ischemic stroke (AIS) due to large artery occlusion (LAO) with high NIHSS (>10), especially in internal carotid artery terminus (ICA-T) are resistant to IV thrombolysis and endovascular thrombectomy is associated with better recanalization rates. IV thrombolysis in large clot burden (>8mm) (LCB) in the middle cerebral artery (MCA) is associated with poor recanalization and may impact outcome. However, thrombectomy in AIS with LAO within 3 hours is performed as secondary therapy after IV thrombolysis. Objectives: To evaluate the feasibility, safety and recanalization rate of primary thrombectomy within 3 hours in AIS with NIHSS >10 from occlusion of MCA with LCB. Additionally, we like to report the functional outcome. Methods: Based on institutionally approved protocol patients with LAO (ICA-T, MCA, vertebral-basilar artery) with LCB within 3 hours were offered primary thrombectomy as an alternative to IV rtPA. They were entered into a stroke database. Patients who underwent primary MCA thrombectomy within 3 hours from 2012 to 2014 were retrospectively analyzed using SAS software. Outcomes were measured using modified Rankin Scale (mRS).Results: 10 patients with MCA occlusion ;mean age 65±15.87 years and mean NIHSS 16±; chose primary thrombectomy after informed consent. Thrombectomy was performed using stent-retriever device in addition to intra-arterial rtPA (2-4 mg). Mean number of passes was 1.4±.7. Near complete (TICI2b) and complete (TICI3) recanalization was observed in all patients. Mean time to recanalization from symptoms onset was 160±37 minutes. Immediate post-thrombectomy, 24 hour and 30 day NIHSS score was 2.6±1.4, 1.9±3.7 and 0 respectively. There was no procedure related complication. Asymptomatic perfusion related hemorrhage developed in 3 patients. 30 day good outcome was observed in all cases (mRS0= 30%, mRS1=50%, mRS2=20%).Conclusion: Our pilot study demonstrates that primary thrombectomy in AIS due to MCA occlusion with LCB is not only feasible and safe, but associated with complete recanalization and good functional outcome. Larger randomized controlled studies are needed.

Abstract W MP8: Stent Retrievers Do Not Encase Clots But Hook Them Within Seconds

Introduction: Stent retriever procedures for clot removal in proximal cerebral arteries are often assumed to securely encase a clot for withdrawal. Hypothesis: We assessed the hypothesis that the interaction of a stent retriever device with a clot in proximal cerebral arteries typically leads to an encasement of the clot after a steady state of clot-device interaction is reached. Methods: We studied how two different stent retrievers (the Trevo and Aperio device) interact with clots made from human blood with a Chandler loop. Therefore, we injected 30 preformed clots of constant length but variable thickness into tapering models of the distal internal carotid artery, the main stem and M2 segments of the middle cerebral artery and filled the remaining lumina with x-ray contrast agent. We then performed stent retrieving procedures with high resolution biplane angiographical imaging to capture all phases of the retrieving procedure without aspiration. We measured penetration depth of the stent struts into the clots, occurrences of clot rupture and the time intervals until a steady state of penetration was achieved. Results: For both stents, we measured stent penetration depth in 60 evenly spaced positions for luminal diameters between 4.2mm and 1.3mm. Above a clot thickness of 2.3mm (Aperio) and 2.1mm (Trevo), a steady state penetration width of 0.5 mm (SD: 0.3 mm) for Trevo and 0.8 mm (SD: 0.4 mm) for Aperio was observed after 2.2s (Trevo) and 5.8 seconds (Aperio) and no encasement was observed. Below a clot thickness of 2 mm, clots were completely encased in 41% (Trevo) and 58% (Aperio), although in both both stents more than 80 % were disrupted. The steady state of penetration was achieved after 3.5s (Trevo, SD: 1.8 s) and 4.8 s (Aperio, SD: 2.1 s). Conclusions: Instead of being encased, thick clots are eccentrically attached to the outer surface of stent retrievers within a few seconds until steady state is reached. This results in the risk of stripping off the clots at the entrance of an aspiration catheter. Encasement of clots is only observed in thin clots at the price of clot disruption with a steady state after a few seconds. Both aspects imply that stent-retriever procedures can only be effective with additional close distance aspiration.

Comparative Analysis of Endovascular Stroke Therapy Using Urokinase, Penumbra System and Retrievable (Solitare) Stent.

BackgroundHigher reperfusion rates have been established with endovascular treatment for acute ischemic stroke patients. There are limited data on the comparative performance of mechanical thrombectomy devices. This study aimed to analyse the efficacy and safety of the stent retriever device (Solitaire stent) by comparing procedure time, angiographic outcome, complication rate and long term clinical outcome with previous chemical thrombolysis and mechanical thrombectomy using penumbra system.MethodsA retrospective single-center analysis was undertaken of all consecutive patients who underwent chemical thrombolysis and mechanical thrombectomy using Penumbra or Solitaire stent retriever from March 2009 to March 2014. Baseline characteristics, rate of successful recanalization (modified Thrombolysis in Cerebral Infarction score 2b-3), symptomatic intracerebral hemorrhage, procedure time, mortality and independent functional outcomes (mRS ≤2) at 3 month were compared across the three method.ResultsOur cohort included 164 patients, mechanical thrombectomy using stent retriever device had a significant impact on recanalization rate and functional independence at 3 months. In unadjusted analysis mechanical thrombectomy using Solitaire stent retriever showed higher recanalization rate than Penumbra system and chemical thrombolysis (75% vs. 64.2% vs. 49.4%, p=0.03) and higher rate of functional independence at 3 month (53.1% vs. 37.7% vs. 35.4%, p=0.213). In view of the interrelationships between all predictors of variables associated with a good clinical outcome, when the chemical thrombolysis was used as a reference, in multiple logistic regression analysis, the use of Solitaire stent retriever showed higher odds of independent functional outcome [odds ratio (OR) 2.62, 95% confidence interval (CI) 0.96-7.17; p=0.061] in comparison with penumbra system (OR 1.57, 95% CI 0.63-3.90; p=0.331).ConclusionOur initial data suggest that mechanical thrombectomy using stent retriever is superior to the mechanical thrombectomy using penumbra system and conventional chemical thrombolysis in achieving higher rates of reperfusion and better outcomes. Randomized clinical trials are needed to establish the actual benefit to specific patient populations.

One-Year MR Angiographic and Clinical Follow-Up after Intracranial Mechanical Thrombectomy Using a Stent Retriever Device

Little is known about the consequences of arterial wall damage that may be due to mechanical endovascular thrombectomy. Our aim was to perform 1-year MR angiographic and clinical follow-up of patients treated with mechanical endovascular thrombectomy using the Solitaire device. Patients with stroke treated between August 2010 and July 2012 were prospectively evaluated with a minimum follow-up of 1 year after mechanical endovascular thrombectomy. Angiographic follow-up was performed on a 3T MR imaging scanner and included intracranial artery TOF MRA and supra-aortic artery gadolinium-enhanced MRA. Images were assessed to detect arterial abnormalities (stenosis, occlusion, dilation) and were compared with the final post-mechanical endovascular thrombectomy run to differentiate delayed and pre-existing abnormalities. Clinical evaluation was performed with the mRS and the 36-Item Short-Form Health Survey questionnaire quality-of-life scale. Thirty-nine patients were angiographically assessed at the mean term of 19 ± 4 months. MRA showed intracranial artery abnormalities in 10 patients, including 5 delayed intracranial artery abnormalities in 4 patients (4 stenoses and 1 dilation), 4 cases of pre-existing intracranial artery stenosis, and 2 occlusions. Pre-existing etiologic cervical artery stenosis or occlusion was observed in 2 patients. All these patients remained asymptomatic during the follow-up period. A significant clinical improvement was observed at 1-year follow-up in comparison with 3-month follow-up (P < .0001), with a good outcome achieved in 62.5% of patients and an acceptable quality of life restored. One-year follow-up identifies delayed asymptomatic arterial abnormalities in patients treated with the Solitaire device.

North American SOLITAIRE Stent-Retriever Acute Stroke Registry

Previous work that predated the availability of the safer stent-retriever devices has suggested that general anesthesia (GA) may have a negative impact on outcomes in patients with acute ischemic stroke undergoing endovascular therapy. We reviewed demographic, clinical, procedural (GA versus local anesthesia [LA], etc), and site-adjudicated angiographic and clinical outcomes data from consecutive patients treated with the Solitaire FR device in the investigator-initiated North American SOLITAIRE Stent-Retriever Acute Stroke (NASA) Registry. The primary outcomes were 90-day modified Rankin Scale, mortality, and symptomatic intracranial hemorrhage. A total of 281 patients from 18 centers were enrolled. GA was used in 69.8% (196/281) of patients. Baseline demographic and procedural factors were comparable between the LA and GA groups, except the former demonstrated longer time-to-groin puncture (395.4±254 versus 337.4±208 min; P=0.04), lower National Institutes of Health Stroke Scale (NIHSS; 16.2±5.8 versus 18.8±6.9; P=0.002), lower balloon-guide catheter usage (22.4% versus 49.2%; P=0.0001), and longer fluoroscopy times (39.5±33 versus 28±22.8 min; P=0.008). Recanalization (thrombolysis in cerebral infarction ≥2b; 72.94% versus 73.6%; P=0.9) and rate of symptomatic intracranial hemorrhage (7.1% versus 11.2%; P=0.4) were similar but modified Rankin Scale ≤2 was achieved in more LA patients, 52.6% versus 35.6% (odds ratio, 1.4 [1.1-1.8]; P=0.01). In multivariate analysis, hypertension, NIHSS, unsuccessful revascularization, and GA use (odds ratio, 3.3 [1.6-7.1]; P=0.001) were associated with death. When only anterior circulation and elective GA patients were included, there was a persistent difference in good outcomes in favor of LA patients (50.7% versus 35.5%; odds ratio, 1.3 [1.01-1.6]; P=0.04). The NASA Registry has demonstrated that clinical outcomes and survival are significantly better in patients treated with LA, without increased symptomatic intracranial hemorrhage risk. Future trials should prospectively evaluate the effect of GA on outcomes.

Clinical experience with the pREset stent retriever for the treatment of acute ischemic stroke—a review of 271 consecutive cases

The purpose of this study was to evaluate the safety and efficacy of the pREset stent retriever in a real-world clinical setting. Patients treated with pREset were selected from a prospectively maintained single-center database. A TICI score ≥2b after ≤3 passes was regarded as successful recanalization. All device-related complications and their clinical significance were reported. Parenchymal hematomas (PH) were classified according to ECASS, adding focal and diffuse subarachnoid hemorrhage (SAH) as categories. A 90-day mRS of 0-2 was defined as favorable outcome. In addition, we separately analyzed patients treated with >3 pREset passes and patients receiving other rescue maneuvers. We included 271 patients. Successful recanalization was achieved in 76.4 %. Device-related complications occurred in 9.2 % of which 2.2 % were clinically significant. PH I, PH II, focal SAH, and diffuse SAH was observed in 5.2, 4.8, 12.2, and 2.2 %, respectively. A total of 39.5 % of patients had favorable clinical outcome. Considering treatments with >3 pREset passes or other rescue procedures, an additional 8.5 and 9.3 % of target vessels were recanalized. The chance of favorable clinical outcome decreased significantly with any kind of rescue therapy. In addition, the rate of PH I was significantly higher in patients treated with >3 pREset passes, whereas all other types of hemorrhage showed no difference. In terms of safety and effectiveness, pREset performed comparably to other stent retriever devices. To avoid futile recanalization and potential additional harm, escalation of therapy beyond three thrombectomy passes should only be performed after careful individual consideration of each case.

Abstract W P25: A Meta-analysis of Randomised Controlled Trials of Endovascular Treatment for Acute Ischaemic Stroke

Introduction: Initial randomised controlled trials (RCTs) showed endovascular treatment of acute ischaemic stroke (AIS) to improve recanalization and functional outcome but recent RCTs have failed to show clinical benefit. Methods: MEDLINE, EMBASE and Cochrane databases were searched for RCTs of endovascular treatment for AIS. Additional RCTs were identified from bibliographies of retrieved articles. Data was extracted on patient characteristics, study intervention, 90-day functional outcome and mortality, 24-hour symptomatic intracerebral haemorrhage (sICH), and post-procedural recanalization. Studies were reviewed independently by 2 trained readers and RCTs of differing methodology were evaluated separately to maintain homogeneity. Results: 12 RCTs were identified with 1910 subjects (mean(SD) age 65(3); 58% male; median(IQR) baseline NIHSS 17(3)) and mean(SD) time for endovascular intervention 4.9(2.9) hours. In 4 RCTs (n=350) comparing intra-arterial thrombolysis (IAT) with no thrombolysis, patients treated with IAT had significantly improved 90-day modified Rankin scale (mRS)&lt;1 (OR: 1.68; 95% CI: 1.20-2.34), 90-day mRS&lt;2 (OR: 1.98; 95% CI: 1.21-3.24) and recanalization (OR: 3.71; 95% CI: 2.80-4.93), reduced 90-day mortality (OR: 0.67; 95% CI: 0.47-0.96) but increased 24-hour sICH (OR: 4.65; 95% CI: 2.73-7.59). In 2 RCTs (n=201) comparing stent-retriever with clot-retrieval devices, patients treated with stent-retrievers had significantly improved 90-day mRS&lt;1 (OR: 1.69; 95% CI: 1.11-2.58), 90-day mRS&lt;2 (OR: 2.56; 95% CI: 1.49-4.38) and recanalization (OR: 1.60; 95% CI: 1.19-2.16), a trend to reduced 90-day mortality (OR: 0.66; 95% CI: 0.41-1.04) and no significant difference in 24-hour sICH (OR: 0.68; 95% CI: 0.18-2.57). No significant differences in patient outcomes were demonstrated in analyses of 3 RCTs (n=443) comparing IAT with intravenous thrombolysis (IVT) or 3 RCTs (n=809) incorporating combined IAT and IVT interventions. Conclusions: IAT for AIS improves recanalization, functional outcome and mortality compared with placebo but not compared with or in addition to IVT. For patients receiving endovascular intervention, stent-retriever devices provide better outcome data than clot-retrieval devices.

Mechanical Thrombectomy in Basilar Artery Thrombosis: Technical Advances and Safety in a 10-Year Experience

Multiple endovascular devices have been used for mechanical thrombectomy (MT) in basilar artery occlusion (BAO) for >10 years. Based on a single-center experience during the course of one decade, we present data on safety and efficacy of previous MT devices compared with modern stent retriever and suction thrombectomy. Eighty-one patients (29 women, 52 men, mean age 61.5 years, range 17-90) with angiographically confirmed BAO that had been treated by MT between 2001 and 2011 were retrospectively evaluated. Patients in group 1 (n = 60) had been treated between 2001 and 2008 with different devices available at that time. Patients in group 2 (n = 21) had been treated by modern stent retriever or local suction devices between 2008 and 2011. Recanalization rate, needle to recanalization time, procedure-related complications, and distal embolization of thrombotic material were recorded and compared. Recanalization rates of 95% were high in both groups. Procedure-related dissection (n = 5) and subarachnoid hemorrhage (n = 9) occurred in group 1 but not in group 2 (p < 0.016). Needle-to-recanalization time was less than half in group 2 compared with group 1 (54.6 vs. 132.3 min, p < 0.01). Frequency of distal embolization was comparable in both groups (47%). High recanalization rates have been achieved since the introduction of MT in BAO. However, modern stent retriever and suction devices allow for safer and more rapid recanalization compared with previous MT devices.

Balloon Guide Catheter Improves Revascularization and Clinical Outcomes With the Solitaire Device

Efficient and timely recanalization is an important goal in acute stroke endovascular therapy. Several studies demonstrated improved recanalization and clinical outcomes with the stent retriever devices compared with the Merci device. The goal of this study was to evaluate the role of the balloon guide catheter (BGC) and recanalization success in a substudy of the North American Solitaire Acute Stroke (NASA) registry. The investigator-initiated NASA registry recruited 24 clinical sites within North America to submit demographic, clinical, site-adjudicated angiographic, and clinical outcome data on consecutive patients treated with the Solitaire Flow Restoration device. BGC use was at the discretion of the treating physicians. There were 354 patients included in the NASA registry. BGC data were reported in 338 of 354 patients in this subanalysis, of which 149 (44%) had placement of a BGC. Mean age was 67.3±15.2 years, and median National Institutes of Health Stroke Scale score was 18. Patients with BGC had more hypertension (82.4% versus 72.5%; P=0.05), atrial fibrillation (50.3% versus 32.8%; P=0.001), and were more commonly administered tissue plasminogen activator (51.6% versus 38.8%; P=0.02) compared with patients without BGC. Time from symptom onset to groin puncture and number of passes were similar between the 2 groups. Procedure time was shorter in patients with BGC (120±28.5 versus 161±35.6 minutes; P=0.02), and less adjunctive therapy was used in patients with BGC (20% versus 28.6%; P=0.05). Thrombolysis in cerebral infarction 3 reperfusion scores were higher in patients with BGC (53.7% versus 32.5%; P<0.001). Distal emboli and emboli in new territory were similar between the 2 groups. Discharge National Institutes of Health Stroke Scale score (mean, 12±14.5 versus 17.5±16; P=0.002) and good clinical outcome at 3 months were superior in patients with BGC compared with patients without (51.6% versus 35.8%; P=0.02). Multivariate analysis demonstrated that the use of BGC was an independent predictor of good clinical outcome (odds ratio, 2.5; 95% confidence interval, 1.2-4.9). Use of a BGC with the Solitaire Flow Restoration device resulted in superior revascularization results, faster procedure times, decreased need for adjunctive therapy, and improved clinical outcome.

The combination of baseline magnetic resonance perfusion-weighted imaging-derived tissue volume with severely prolonged arterial-tissue delay and diffusion-weighted imaging lesion volume is predictive of MCA-M1 recanalization in patients treated with endovascular thrombectomy

IntroductionIndices of collateral flow deficit derived from MR perfusion imaging that are predictive of MCA-M1 recanalization after intravenous thrombolysis have been recently reported. Our objective was to test the performance of such MRI-derived collateral flow indices for prediction of recanalization after endovascular thrombectomy.MethodsFifty-seven patients with MCA-M1 occlusion evaluated with multimodal MRI prior to thrombectomy were included. Bayesian processing allowed quantification of collateral perfusion indices like the volume of tissue with severely prolonged arterial-tissue delay (>6 s) (VolATD6). Baseline DWI lesion volume was also measured. Correlations with angiographic collateral flow grading and post-thrombectomy recanalization were assessed.ResultsVolATD6 < 27 ml or DWI lesion volume <15 ml provide the most accurate diagnosis of excellent collateral supply (p < 0.0001). The combination of VolATD6 > 27 ml and DWI lesion volume >15 ml significantly discriminates recanalizers versus nonrecanalizers (whole cohort, p = 0.032; MERCI cohort (n = 50), p = 0.024). When both criteria are positive, 76.2 % of the patients treated with the MERCI retriever do not fully recanalize (p = 0.024). In multivariate analysis, the aforementioned combined criterion and the angiographic collateral grade are the only independent predictors of recanalization with the MERCI retriever (p = 0.015 and 0.029, respectively).ConclusionBayesian arterial-tissue delay maps and DWI maps provide a non-invasive assessment of the degree of collateral flow and a combined index that is predictive of MCA-M1 recanalization after endovascular thrombectomy. Further studies are needed to evaluate the accuracy of this index in patients treated with novel stent retriever devices.

Thrombectomy in Patients With Large Cerebral Artery Occlusion

The Trevo device, a new stent retriever, may be utilized in patients with large cerebral artery occlusion. Fifty patients with large cerebral artery occlusion and treated with the Trevo device were analyzed. Patients may have received intravenous thrombolysis as a bridging concept in addition to thrombectomy. Outcome and recanalization parameters were documented using the National Institutes of Health Scale, the modified Ranking Scale (mRS) and Thrombolysis in Cerebral Infarction (TICI) score. In all, 82% (95% confidence interval [CI]: 69%-91%) were documented with TICI 2b and 3. Good clinical outcome after 90 days (mRS ≤ 2) was assessed in 61% (95% CI: 46%-75%). Symptomatic intracerebral hemorrhage occurred in 6 patients (12%, 95% CI: 1%-17%). The overall mortality rate was 14% (95% CI: 6%-27%). Thrombectomy with the new stent retriever device is feasible and effective and has an acceptable risk of intra-cerebral hemorrhage even in combination with pharmacological revascularization techniques.

Emergency Cervical Internal Carotid Artery Stenting in Combination with Intracranial Thrombectomy in Acute Stroke

In past years, thrombectomy has become a widely used procedure in interventional neuroradiology for the treatment of acute intracranial occlusions. However, in 10-20% of patients, there are additional occlusions or stenotic lesions of the ipsilateral cervical internal carotid artery. The purpose of this study was to evaluate the feasibility of emergency carotid artery stent placement in combination with intracranial thrombectomy and the clinical outcome of the treated patients. We analyzed clinical and angiographic data of patients who underwent emergency cervical ICA stent placement and intracranial thrombectomy with stent-retriever devices in our institution between November 2009 and July 2012. Recanalization was assessed according to the Thrombolysis in Cerebral-Infarction score. Clinical outcome was evaluated at discharge (NIHSS) and after 3 months (mRS). Overall, 24 patients were treated. The mean age was 67.2 years; mean occlusion time, 230.2 minutes. On admission, the median NIHSS score was 18. In all patients, the Thrombolysis in Cerebral Infarction score was zero before the procedure. Stent implantation was feasible in all cases. In 15 patients (62.5%), a Thrombolysis in Cerebral Infarction score ≥ 2b could be achieved. Six patients (25%) improved ≥10 NIHSS points between admission and discharge. After 90 days, the median mRS score was 3.0. Seven patients (29.2%) had a good clinical outcome (mRS 0-2), and 4 patients (16.6%) died, 1 due to fatal intracranial hemorrhage. Overall, symptomatic intracranial hemorrhage occurred in 4 patients (16.6%). Emergency ICA stent implantation was technically feasible in all patients, and the intracranial recanalization Thrombolysis in Cerebral Infarction score of ≥2b was reached in a high number of patients. Clinical outcome and mortality seem to be acceptable for a cohort with severe stroke. However, a high rate of symptomatic intracranial hemorrhage occurred in our study.

Prospective, Multicenter, Single-Arm Study of Mechanical Thrombectomy Using Solitaire Flow Restoration in Acute Ischemic Stroke

Mechanical thrombectomy using stent retriever devices have been advocated to increase revascularization in intracranial vessel occlusion. We present the results of a large prospective study on the use of the Solitaire Flow Restoration in patients with acute ischemic stroke. Solitaire Flow Restoration Thrombectomy for Acute Revascularization was an international, multicenter, prospective, single-arm study of Solitaire Flow Restoration thrombectomy in patients with large vessel anterior circulation strokes treated within 8 hours of symptom onset. Strict criteria for site selection were applied. The primary end point was the revascularization rate (thrombolysis in cerebral infarction ≥2b) of the occluded vessel as determined by an independent core laboratory. The secondary end point was the rate of good functional outcome (defined as 90-day modified Rankin scale, 0-2). A total of 202 patients were enrolled across 14 comprehensive stroke centers in Europe, Canada, and Australia. The median age was 72 years, 60% were female patients. The median National Institute of Health Stroke Scale was 17. Most proximal intracranial occlusion was the internal carotid artery in 18%, and the middle cerebral artery in 82%. Successful revascularization was achieved in 79.2% of patients. Device and procedure-related severe adverse events were found in 7.4%. Favorable neurological outcome was found in 57.9%. The mortality rate was 6.9%. Any intracranial hemorrhagic transformation was found in 18.8% of patients, 1.5% were symptomatic. In this single-arm study, treatment with the Solitaire Flow Restoration device in intracranial anterior circulation occlusions results in high rates of revascularization, low risk of clinically relevant procedural complications, and good clinical outcomes in combination with low mortality at 90 days. http://www.clinicaltrials.gov. Unique identifier: NCT01327989.

Endovascular therapy for acute stroke: Quo vadis?

Abstract Endovascular therapy (EVT) has gained vogue in the management of patients with acute stroke. Newer stent-retriever devices have led to better recanalization rates. In many centers, EVT is slowly being used as an add on to or in some instances, even as an alternative to intravenous tissue plasminogen activator (IV tPA). The publication of the results of the SYNTHESIS expansion, Interventional Management of Stroke III and Mechanical Retrieval Recanalization of Stroke Clots Using Embolectomy trials in 2013 has questioned the enthusiastic use of EVT in acute stroke. They demonstrate that EVT (using a variety of devices) is no superior to IV tPA in the management of acute stroke. In the light of these controversial findings, we review the current status of EVT in the management of acute stroke.

Endovascular therapy in acute ischemic stroke: The way forward after results from the IMS 3, SYNTHESIS and MR Rescue trials

AbstractEndovascular therapy (EVT) has gained vogue in the management of patients with acute stroke. Newer stent-retriever devices have led to better recanalization rates. In many centers, EVT is slowly being used as an add on to or in some instances, even as an alternative to intravenous tissue plasminogen activator (IV tPA). The publication of the results of the SYNTHESIS expansion, Interventional Management of Stroke III and Mechanical Retrieval Recanalization of Stroke Clots Using Embolectomy trials in 2013 has questioned the enthusiastic use of EVT in acute stroke. They demonstrate that EVT (using a variety of devices) is no superior to IV tPA in the management of acute stroke. In the light of these controversial findings, we review the current status of EVT in the management of acute stroke.

Solitaire Flow Restoration Thrombectomy for Acute Ischemic Stroke

The promising results of the Solitaire Flow Restoration (FR) With the Intention for Thrombectomy (SWIFT) trial recently led to Food and Drug Administration (FDA) approval of the Solitaire FR stent retriever device for recanalization of cerebral vessels in patients with acute ischemic stroke. To report the early postmarket experience with this device since its FDA approval in the United States, which has not been previously described. We conducted a retrospective analysis of consecutive acute ischemic strokes cases treated between March 2012 and July 2012 at 10 United States centers where the Solitaire FR was used as a single device or in conjunction with other intraarterial endovascular approaches. A total of 101 patients were identified (mean age, 64.7 years; mean admission National Institutes of Health Stroke Scale [NIHSS] score, 17.6). Intravenous thrombolysis was administered in 39% of cases; other endovascular techniques were utilized in conjunction with the Solitaire FR in 52%. Successful recanalization (Thrombolysis in Myocardial Infarction 2/3) was achieved in 88%. The rate of symptomatic intracranial hemorrhage within the first 24 hours was 15%. In-hospital mortality was 26%. At 30 days, 38% of patients had favorable functional outcome (modified Rankin scale score ≤2). Severity of NIHSS score on admission was a strong predictor of poor outcome. Our study shows that a variety of other endovascular approaches are used in conjunction with Solitaire FR in actual practice in the United States. Early postmarket results suggest that Solitaire FR is an effective tool for endovascular treatment of acute ischemic stroke.

Abstract TP9: Solitaire FR Thrombectomy For Acute Stroke: Real-world Experience After FDA Approval

Background and Purpose: Based on promising results of the Solitaire FR With the Intention for Thrombectomy (SWIFT) trial, Solitaire FR stent retriever device recently received the Food and Drug Administration (FDA) approval for recanalization of cerebral vessels in patients with acute ischemic stroke. Real world experience with this device since its FDA approval in the United States has not been previously described. Methods: We conducted retrospective analysis of consecutive acute ischemic strokes cases from March 2012 to July 2012 in 10 centers within the United States, where Solitaire FR was used as a single device or in conjunction with other intra-arterial endovascular approaches. Results: A total of 107 patients were identified (mean age, 64 years; male gender, 51%; mean admission NIHSS score 17). Mean time from symptom onset to angiogram (groin puncture) was 4 hrs 47 min. Intravenous thrombolysis with tissue plasminogen activator (tPA) was administered in 37% of cases. Other endovascular techniques utilized in conjunction with Solitaire FR included intra-arterial thrombolysis with tPA (12% of patients), aspiration thrombectomy with Penumbra system (29%) and stenting (17%). Complete recanalization (TIMI 2-3) was achieved in 88% of patients. The rate of sICH within the first 24 hours was 15%. In-hospital mortality was 24%. 30-day clinical follow up data was available on 82 (77%) patients. Of those, 28 patients (34%) had favorable functional outcome (defined as modified Ranking Scale,mRS≤2) and 22 patients (27%) had excellent functional outcome (mRS≤1) at 30 days. Three or more passes with the Solitaire device was associated with a higher incidence of mortality compared with patients requiring 1 or 2 passes only (43% and 18% respectively, p = 0.011). No statistically significant correlation between clot location or length and outcome was evident. Use of other devices with the Solitaire FR was correlated with worsened outcome (p=0.037). Conclusions: This is the first study describing real-world experience with Solitaire FR device outside the SWIFT trial in the United States. Out study shows that variety of other endovascular approaches are used in conjunction with Solitaire FR.

Advanced imaging to extend the therapeutic time window of acute ischemic stroke

Reperfusion therapy for acute stroke has evolved from the initial use of intravenous tissue plasminogen activator (tPA) within 3 hours of symptom onset to more recent guideline-recommended use up to 4.5 hours. In addition, endovascular therapy is increasingly utilized for stroke treatment and is typically initiated up to 8 hours after onset. Recent studies demonstrate that imaging of the ischemic penumbra with diffusion/perfusion magnetic resonance imaging (MRI) can identify subgroups of patients who are likely to improve following successful reperfusion (Target Mismatch profile) and others who are at increased risk for hemorrhage and poor clinical outcomes (Malignant profile). New data indicate that stent retriever devices provide better recanalization efficacy and clinical outcomes than the previously available mechanical thrombectomy devices. Going forward, we believe that the use of penumbral imaging with validated MRI techniques, as well as the currently less well-validated computed tomography (CT) perfusion approach, will maximize benefit and reduce the risk of adverse events and poor outcomes when used both early after stroke onset and at later time points. New trials that feature diffusion/perfusion MRI or CT perfusion-based patient selection for treatment with intravenous tPA and or endovascular therapies versus nonreperfused control groups are planned or in progress. We predict that these trials will confirm the hypothesis that penumbral imaging can enhance patient selection and extend the therapeutic time window for acute ischemic stroke.

Recanalization with Stent-Retriever Devices in Patients with Wake-Up Stroke

Stent-retriever devices play an increasing role in the interventional treatment of acute stroke patients, because fast recanalization can be achieved. The purpose of this study was to evaluate the feasibility of stent-retriever recanalization in patients with wake-up stroke in the anterior circulation. We retrospectively analyzed clinical and angiographic data of 19 consecutive patients with wake-up stroke who were treated with stent-retriever devices between 2009 and October 2011. Recanalization was assessed by using the Thrombolysis in Cerebral Infarction score. Clinical outcome was evaluated at discharge and after 90 days by using the modified Rankin Scale. Median NIHSS score at admission was 17 (IQR, 15-20). Before the procedure, the TICI score was 0 in 18 patients and 1 in 1 patient. Recanalization with stent-retriever devices was successful (TICI ≥ 2) in 94.7%. Mean time to flow restoration was 36.7 minutes and to complete recanalization 83.7 minutes. Symptomatic intracranial hemorrhage occurred in 4 patients (21.1%). Eight patients had an NIHSS improvement of ≥4 points between admission and discharge. After 90 days, 2 (10.5%) of our patients presented with mRS 0-2; seven (36.8%) died. Despite successful and rapid recanalization with stent-retriever devices, good clinical outcome in patients with wake-up stroke is achieved in a minority of patients. Clinical outcome remains poor. Bleeding rates were higher compared with recanalization procedures within 6 hours after stroke onset.