Procedural approaches and angiographic signs predicting first-pass recanalization in patients treated with mechanical thrombectomy for acute ischaemic stroke

Remote Teleproctoring with the TEGUS System for Mechanical Thrombectomy in a Non-Comprehensive Stroke Center: Initial Preliminary Data On Clinical Experience

PURPOSE

Mechanical thrombectomy (MT) is typically performed by experienced neurointerventional radiologists. However, logistical and geographic limitations often hinder access to rapid MT. This study reports the first clinical experience using TEGUS teleproctoring to support MT conducted by general interventional radiologists (IR) at non-comprehensive stroke centers, compared to on-site proctoring outcomes.

METHODS

The Arnau de Vilanova Hospital in Spain used to transfer stroke patients requiring MT to a comprehensive Stroke Center 160 km away. To overcome COVID-19 mobility restrictions, the Tegus Teleproctoring System was installed. Before teleproctoring, the general interventional radiologist underwent six months of neurointerventional training at a primary stroke center. From April 2021 to May 2023, general IR conducted MT either with on-site proctor supervision or teleproctoring support. We aim to compare clinical outcome of patients receiving MT according to proctoring method.

RESULTS

During the study, 49 MTs were performed: 15 with TEGUS teleproctoring and 34 with on-site proctoring. Both groups had similar baseline characteristics, except for NIHSS scores (Tegus 9 [IQR 6-20] vs 18 [IQR 12-22], p = 0.034). No significant differences were found in door-to-revascularization time (82 ± 28.2 vs 84 ± 26.4) min, p = (0.895). The final mTICI distribution and 90-day mRS scores were comparable after adjusting by stroke severity. There were no reports of symptomatic intracranial hemorrhage in either group.

CONCLUSION

This study shows the feasibility of Tegus remote teleproctoring during emergent cases of MT in a remote hospital. It could improve the learning curve of interventional radiologists with limited experience in MT, and lower the territorial inequity associated to MT.

Mechanical thrombectomy with a new intermediate balloon catheter combining the BGC and DAC features: Initial clinical experience with the iNedit device

INTRODUCTION

The iNedit balloon distal access catheter is a novel thrombectomy device. It has an inner diameter of 0.058″, proximal outer diameter of 2.13 mm, and distal outer diameter of 1.67mm. It is compatible with a 0.088″ guide catheter and includes a balloon located 5 cm from the catheter tip, enabling proximal flow restriction and combined therapy with stent retrievers. We investigate the appraisal of the use, safety, and efficacy of the iNedit catheter in the first-in-human study.

METHODS

In the preliminary cases that demanded training on the product previous to a multicentric study, prospective data were collected on 22 consecutive patients treated with the iNedit catheter to perform thrombectomy for acute ischemic stroke due to large vessel occlusion within 24 h. The outcome measures consisted of several evaluations of user experience rated on a 5-point scale ranging from 1 (bad) to 5 (excellent), as well as assessments of procedural safety outcomes such as artery perforation and arterial occlusion, procedural efficacy outcomes including first-pass effect (Thrombolysis In Cerebral Infarction [TICI] 2c/3) and final recanalization (TICI 2b/3), and clinical efficacy outcomes such as a 3-month 0-2 modified Rankin Scale (mRS).

RESULTS

The mean age was 72 ± 12 years old; median National Institute Health Stroke Scale was 17 (11-19). Sites of primary occlusion were: 2 internal carotid artery, 12 M1-MCA, 7 M2-MCA, and one P1. Median score evaluation of the appraisal of use was 4- IQR [4-5]. The median number of passes was 1 [IQR 1-2]. First pass complete recanalization rate was 50% and the final recanalization rate was 94.45%. No artery perforation and arterial occlusion. Good functional outcome mRS 0-2 was achieved in 50% of patients.

CONCLUSIONS

In this initial clinical experience, iNedit device achieved a high rate of first-pass effect and final recanalization rate with no safety concerns, thus favoring a high percentage of good clinical outcomes.

Combined technique as first approach in mechanical thrombectomy: Efficacy and safety of REACT catheter combined with stent retriever

INTRODUCTION

Mechanical thrombectomy (MT) with combined treatment including both a stent retriever and distal aspiration catheter may improve recanalization rates in patients with acute ischemic stroke (AIS) due to large vessel occlusion (LVO). Here, we evaluated the effectiveness and safety of the REACT aspiration catheter used with a stent retriever.

METHODS

This prospective study included consecutive adult patients who underwent MT with a combined technique using REACT 68 and/or 71 between June 2020 and July 2021. The primary endpoints were final and first pass mTICI 2b-3 and mTICI 2c-3 recanalization. Analysis was performed after first pass and after each attempt. Secondary safety outcomes included procedural complications, symptomatic intracranial hemorrhage (sICH) at 24 h, in-hospital mortality, and 90-day functional independence (modified Rankin Scale [mRS] 0-2).

RESULTS

A total of 102 patients were included (median age 78; IQR: 73-87; 50.0% female). At baseline, median NIHSS score was 19 (IQR: 11-21), and ASPECTS was 9 (IQR: 8-10). Final mTICI 2b-3 recanalization was achieved in 91 (89.2%) patients and mTICI 2c-3 was achieved in 66 (64.7%). At first pass, mTICI 2b-3 was achieved in 55 (53.9%) patients, and mTICI 2c-3 in 37 (36.3%). The rate of procedural complications was 3.9% (4/102), sICH was 6.8% (7/102), in-hospital mortality was 12.7% (13/102), and 90-day functional independence was 35.6% (36/102).

CONCLUSION

A combined MT technique using a stent retriever and REACT catheter resulted in a high rate of successful recanalization and first pass recanalization in a sample of consecutive patients with AIS due to LVO in clinical use.

First-Pass Recanalization with EmboTrap II in Acute Ischemic Stroke (FREE-AIS): A Multicenter Prospective Study

OBJECTIVE

We aimed to evaluate the efficacy of EmboTrap II in terms of first-pass recanalization and to determine whether it could yield favorable outcomes.

MATERIALS AND METHODS

In this multicenter, prospective study, we consecutively enrolled patients who underwent mechanical thrombectomy using EmboTrap II as a front-line device. The primary outcome was the first pass effect (FPE) rate defined by modified Thrombolysis In Cerebral Infarction (mTICI) grade 2c or 3 by the first pass of EmboTrap II. In addition, modified FPE (mFPE; mTICI grade 2b-3 by the first pass of EmboTrap II), successful recanalization (final mTICI grade 2b-3), and clinical outcomes were assessed. We also analyzed the effect of FPE on a modified Rankin Scale (mRS) score of 0-2 at 3 months.

RESULTS

Two hundred-ten patients (mean age ± standard deviation, 73.3 ± 11.4 years; male, 55.7%) were included. Ninety-nine patients (47.1%) had FPE, and mFPE was achieved in 150 (71.4%) patients. Successful recanalization was achieved in 191 (91.0%) patients. Among them, 164 (85.9%) patients underwent successful recanalization by exclusively using EmboTrap II. The time from groin puncture to FPE was 25.0 minutes (interquartile range, 17.0-35.0 minutes). Procedure-related complications were observed in seven (3.3%) patients. Symptomatic intracranial hemorrhage developed in 14 (6.7%) patients. One hundred twenty-three (58.9% of 209 completely followed) patients had an mRS score of 0-2. Sixteen (7.7% of 209) patients died during the follow-up period. Patients who had successful recanalization with FPE were four times more likely to have an mRS score of 0-2 than those who had successful recanalization without FPE (adjusted odds ratio, 4.13; 95% confidence interval, 1.59-10.8; p = 0.004).

CONCLUSION

Mechanical thrombectomy using the front-line EmboTrap II is effective and safe. In particular, FPE rates were high. Achieving FPE was important for an mRS score of 0-2, even in patients with successful recanalization.

Endovascular treatment of acute ischemic stroke with a fully radiopaque retriever: A randomized controlled trial

Objective

The Neurohawk retriever is a new fully radiopaque retriever. A randomized controlled non-inferiority trial was conducted to compare the Neurohawk and the Solitaire FR in terms of safety and efficacy. In order to evaluate the efficacy and safety of endovascular treatment in acute ischemic stroke (AIS) caused by intracranial atherosclerotic disease (ICAD) larger vessel occlusion (LVO), a sub-analysis was performed.

Methods

Acute ischemic stroke patients aged 18-80 years with LVO in the anterior circulation were randomly assigned to undergo thrombectomy with either the Neurohawk or the Solitaire FR. The primary efficacy endpoint was successful reperfusion (mTICI 2b-3) rate by the allocated retriever. A relevant non-inferiority margin was 12.5%. Safety outcomes were symptomatic intracranial hemorrhage (sICH) and all-cause mortality within 90 days. Secondary endpoints included first-pass effect (FPE), modified FPE, and favorable outcomes at 90 days. In subgroup analysis, the patients were divided into the ICAD group and non-ICAD group according to etiology, and baseline characteristics, angiographic, and clinical outcomes were compared.

Results

A total of 232 patients were involved in this analysis (115 patients in the Neurohawk group and 117 in the Solitaire group). The rates of successful reperfusion with the allocated retriever were 88.70% in the Neurohawk group and 90.60% in the Solitaire group (95%CI of the difference, -9.74% to 5.94%; p = 0.867). There were similar results in FPE and mFPE in both groups. The rate of sICH seemed higher in the Solitaire group (13.16% vs. 7.02%, p = 0.124). All-cause mortality and favorable outcome rates were comparable as well. In subgroup analysis, 58 patients were assigned to the ICAD group and the remaining 174 to the non-ICAD group. The final successful reperfusion and favorable outcome rates showed no statistically significant differences in two groups. Mortality within 90 days was relatively lower in the ICAD group (6.90% vs. 17.24%; p = 0.054).

Conclusion

The Neurohawk retriever is non-inferior to the Solitaire FR in the mechanical thrombectomy of large vessel occlusion-acute ischemic stroke (LVO-AIS). The sub-analysis suggested that endovascular treatment including thrombectomy with the retriever and essential rescue angioplasty is effective and safe in AIS patients with intracranial atherosclerotic disease-larger vessel occlusion (ICAD-LVO).

Clinical trial registration

https://clinicaltrials.gov/ct2/show/NCT04995757, number: NCT04995757.

Magnetic resonance imaging quantitative T2* mapping to predict the red blood cell content of in vivo thrombi retrieved from patients with large vessel occlusions in acute ischemic stroke

BACKGROUND AND PURPOSE

Magnetic resonance imaging quantitative T2* mapping has shown reliable identification of thrombus red blood cell content in vitro. The thrombus composition has been in vivo, associated with outcomes after endovascular therapy for acute ischemic stroke. We aim to analyze the red blood cell content of thrombi retrieved from patients with large vessel occlusions in relation to the thrombus-T2* relaxation time in magnetic resonance imaging.

MATERIAL AND METHODS

Consecutive acute ischemic stroke patients treated by endovascular therapy were scanned with an magnetic resonance imaging quantitative T2* mapping sequence. Quantitative histologic evaluations of red blood cell content were performed. A linear regression assessed the association between vascular risk factors, comorbidities, antithrombotic drugs intake, baseline National Institutes of Health Stroke Scale (NIHSS), intravenous thrombolysis before endovascular therapy, time between onset and groin puncture, patient's outcome at 3 months, magnetic resonance imaging quantitative T2* mapping results, and the red blood cell content of thrombi. The correlation between the mean thrombus-T2* relaxation time and red blood cell content was assessed by calculating the Pearson correlation coefficient.

RESULTS

Among 31 thrombi, 16 were "Fibrin rich" and 15 "red blood cell dominant." The median red blood cell content was 39 (range, 0-90; interquartile range, 37). The median (interquartile range) thrombus-T2* relaxation time was shorter in "red blood cell dominant" thrombi (21, interquartile range 6) than in "Fibrin rich" thrombi (24, interquartile range 7), without significant difference (p = 0.15), as shown in the Box plot. An inverse correlation between thrombus-T2* relaxation time and red blood cell content was found, with a correlation coefficient of -0.41 (95% CI, -0.67 to -0.08, p = 0.02).

CONCLUSION

Our study shows that a shorter thrombus-T2* relaxation time is related to a higher red blood cell content within in vivo thrombi.

The claw sign predicts first-pass effect in mechanical thrombectomy for cerebral large vessel occlusion in the anterior circulation

Background:

Mechanical thrombectomy (MT) is an effective treatment for acute cerebral large vessel occlusion (LVO). Complete recanalization of vessels in a single procedure is defined as the first-pass effect (FPE) and is associated with good prognosis. In this study, angiographic clot protruding sign termed the “claw sign,” was examined as candidate preoperative imaging factor for predicting the FPE.

Methods:

We retrospectively analyzed data from 91 consecutive patients treated for acute LVO in the anterior circulation by MT between January 2014 and December 2019. The claw sign was defined as a thrombus that protruded proximally by more than half of the diameter of the parent artery. Radiological findings such as claw sign, clinical and etiological features, and outcomes were compared between groups with and without successful FPE. Multivariate analysis was conducted to evaluate perioperative factors associated with FPE.

Results:

FPE was achieved in 26 of 91 (28.6%) patients and the claw sign was observed in 34 of 91 (37.4%) patients. The claw sign was significantly more frequent in the successful FPE group than in the failed FPE group (53.8% vs. 30.8%; P = 0.040). After the multivariate analysis, the claw sign was the only pretreatment parameter that could predict FPE (odds ratio, 2.67; 95% confidence interval, 1.01–7.06; P = 0.047).

Conclusion:

The claw sign is an angiographic imaging factor that might predict FPE after MT for anterior circulation acute ischemic stroke.

Intravenous Alteplase is Associated with First Pass Effect in Stent-retriever but not ADAPT Thrombectomy : Post Hoc Analysis of the SKIP Study

PURPOSE

To investigate the effect of alteplase, either combined with stent-retriever thrombectomy or a direct aspiration first pass technique (ADAPT), in patients with large-vessel occlusion stroke.

METHODS

This was a retrospective post hoc analysis of data from The Direct Mechanical Thrombectomy in Acute LVO Stroke (SKIP) study. Patients were divided into two groups according to the first-line thrombectomy technique: stent-retriever and ADAPT. Each group was further divided into two subgroups, namely MT and MT + alteplase. The procedural outcomes, such as first pass effect (FPE) ratio and number of passes, were evaluated. The clinical outcomes included mRS score at 3 months.

RESULTS

A total of 180 patients were included (116 in the stent-retriever group and 64 in the ADAPT group). No interaction was detected between the first-line technique and alteplase administration. In the stent-retriever group, after adjusting for factors associated with FPE, the adjusted odds ratio (95% confidence interval) of FPE of the MT + alteplase subgroup versus the MT subgroup was 3.57 (1.5-8.48) and in the ADAPT group it was 1.35 (0.37-4.91). With alteplase, the number of passes decreased with adjusted odds ratios of 0.59 (0.37-0.93) in the stent-retriever group but not in the ADAPT group. In both first-line technique groups, clinical outcomes did not differ between subgroups.

CONCLUSION

In the SKIP study, alteplase administration was associated with increased FPE when combined with stent-retriever thrombectomy, but not with ADAPT. We found no differences in the clinical outcomes.

First pass effect vs multiple passes complete reperfusion: A retrospective study

BACKGROUND AND PURPOSE

First pass effect (FPE) is defined as achieving modified treatment in cerebral infarction (mTICI) grade 2c/3 reperfusion from the first pass and is associated with more favorable outcomes. We aimed to compare FPE and non-FPE using a large database and further compare first-pass mTICI 2b with multiple passes mTICI 3.

METHODS

A retrospective cohort study of acute ischemic stroke patients who received mechanical thrombectomy at a high-volume center was performed. Baseline characteristics and outcomes including rates of discharge and 90-day functional independence (modified Rankin Scale ≤2), mortality, symptomatic, and asymptomatic intracerebral hemorrhage were compared.

RESULTS

Of the 637 patients included, 294 achieved FPE; 161 patients had multiple passes mTICI 3 and 36 had first pass mTICI 2b. Propensity-score matching resulted in 211 matched pairs for FPE vs non-FPE, and 30 matched pairs for multiple passes mTICI 3 vs first pass mTICI 2b. The FPE group had significantly more instances of discharge (33.6% vs 19.4%, p = 0.001) and 90-day functional independence (51.7% vs 40.8%, p = 0.032), and lower rates of mortality (18.0% vs 27.5%, p = 0.027) compared to non-FPE. There was no significant difference between first pass mTICI 2b and multiple passes mTICI 3 concerning any studied outcomes.

CONCLUSIONS

First pass mTICI 2c/3 is safer and is associated with higher rates of functional independence. We did not observe a significant difference between first pass mTICI 2b and multiple passes mTICI 3. The limitations of this study prevent us from drawing conclusions related to the difference between them and calls for future large-scale studies to explore that further.

Factors Influencing Recanalization After Mechanical Thrombectomy With First-Pass Effect for Acute Ischemic Stroke: A Systematic Review and Meta-Analysis

Background: First-pass effect (FPE) is increasingly recognized as a predictor of good outcome in large vessel occlusion (LVO). This systematic review and meta-analysis aimed to elucidate the factors influencing recanalization after mechanical thrombectomy (MT) with FPE in treating acute ischemic stroke (AIS).

Methods: Main databases were searched for relevant randomized controlled trials (RCTs) and observational studies reporting influencing factors of MT with FPE in AIS. Recanalization was assessed by the modified thrombolysis in cerebral ischemia (mTICI) score. Both successful (mTICI 2b-3) and complete recanalization (mTICI 2c-3) were observed. Risk of bias was assessed through different scales according to study design. The I² statistic was used to evaluate the heterogeneity, while subgroup analysis, meta-regression, and sensitivity analysis were performed to investigate the source of heterogeneity. Visual measurement of funnel plots was used to evaluate publication bias.

Results: A total of 17 studies and 6,186 patients were included. Among them, 2,068 patients achieved recanalization with FPE. The results of meta-analyses showed that age [mean deviation (MD):1.21,95% confidence interval (CI): 0.26–2.16; p = 0.012], female gender [odds ratio (OR):1.12,95% CI: 1.00–1.26; p = 0.046], diabetes mellitus (DM) (OR:1.17,95% CI: 1.01–1.35; p = 0.032), occlusion of internal carotid artery (ICA) (OR:0.71,95% CI: 0.52–0.97; p = 0.033), occlusion of M2 segment of middle cerebral artery (OR:1.36,95% CI: 1.05–1.77; p = 0.019), duration of intervention (MD: −27.85, 95% CI: −42.11–13.58; p < 0.001), time of onset to recanalization (MD: −34.63, 95% CI: −58.45–10.81; p = 0.004), general anesthesia (OR: 0.63,95% CI: 0.52–0.77; p < 0.001), and use of balloon guide catheter (BGC) (OR:1.60,95% CI: 1.17–2.18; p = 0.003) were significantly associated with successful recanalization with FPE. At the same time, age, female gender, duration of intervention, general anesthesia, use of BGC, and occlusion of ICA were associated with complete reperfusion with FPE, but M2 occlusion and DM were not.

Conclusion: Age, gender, occlusion site, anesthesia type, and use of BGC were influencing factors for both successful and complete recanalization after first-pass thrombectomy. Further studies with more comprehensive observations indexes are need in the future.

Effect of First-Pass Reperfusion on Outcome After Endovascular Treatment for Ischemic Stroke

Background

First‐pass reperfusion (FPR) is associated with favorable outcome after endovascular treatment. It is unknown whether this effect is independent of patient characteristics and whether FPR has better outcomes compared with excellent reperfusion (Expanded Thrombolysis in Cerebral Infarction [eTICI] 2C‐3) after multiple‐passes reperfusion. We aimed to evaluate the association between FPR and outcome with adjustment for patient, imaging, and treatment characteristics to single out the contribution of FPR.

Methods and Results

FPR was defined as eTICI 2C‐3 after 1 pass. Multivariable regression models were used to investigate characteristics associated with FPR and to investigate the effect of FPR on outcomes. We included 2686 patients of the MR CLEAN (Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands) Registry. Factors associated with FPR were as follows: history of hyperlipidemia (adjusted odds ratio [OR], 1.05; 95% CI, 1.01–1.10), middle cerebral artery versus intracranial carotid artery occlusion (adjusted OR, 1.11; 95% CI, 1.06–1.16), and aspiration versus stent thrombectomy (adjusted OR, 1.07; 95% CI, 1.03–1.11). Interventionist experience increased the likelihood of FPR (adjusted OR, 1.03 per 50 patients previously treated; 95% CI, 1.01–1.06). Adjusted for patient, imaging, and treatment characteristics, FPR remained associated with a better 24‐hour National Institutes of Health Stroke Scale (NIHSS) score (−37%; 95% CI, −43% to −31%) and a better modified Rankin Scale (mRS) score at 3 months (adjusted common OR, 2.16; 95% CI, 1.83–2.54) compared with no FPR (multiple‐passes reperfusion+no excellent reperfusion), and compared with multiple‐passes reperfusion alone (24‐hour NIHSS score, (−23%; 95% CI, −31% to −14%), and mRS score (adjusted common OR, 1.45; 95% CI, 1.19–1.78)).

Conclusions

FPR compared with multiple‐passes reperfusion is associated with favorable outcome, independently of patient, imaging, and treatment characteristics. Factors associated with FPR were the experience of the interventionist, history of hyperlipidemia, location of occluded artery, and use of an aspiration device compared with stent thrombectomy.

Systematic review and meta-analysis of current rates of first pass effect by thrombectomy technique and associations with clinical outcomes

BACKGROUND

First pass effect (FPE) in mechanical thrombectomy is thought to be associated with good clinical outcomes.

OBJECTIVE

To determine FPE rates as a function of thrombectomy technique and to compare clinical outcomes between patients with and without FPE.

METHODS

In July 2020, a literature search on FPE (defined as modified Thrombolysis in Cerebral Infarction (TICI) 2c-3 after a single pass) and modified FPE (mFPE, defined as TICI 2b-3 after a single pass) and mechanical thrombectomy for stroke was performed. Using a random-effects meta-analysis, we evaluated the following outcomes for both FPE and mFPE: overall rates, rates by thrombectomy technique, rates of good neurologic outcome (modified Rankin Scale score ≤2 at day 90), mortality, and symptomatic intracerebral hemorrhage (sICH) rate.

RESULTS

Sixty-seven studies comprising 16 870 patients were included. Overall rates of FPE and mFPE were 28% and 45%, respectively. Thrombectomy techniques shared similar FPE (p=0.17) and mFPE (p=0.20) rates. Higher odds of good neurologic outcome were found when we compared FPE with non-FPE (56% vs 41%, OR=1.78) and mFPE with non-mFPE (57% vs 44%, OR=1.73). FPE had a lower mortality rate (17% vs 25%, OR=0.62) than non-FPE. FPE and mFPE were not associated with lower sICH rate compared with non-FPE and non-mFPE (4% vs 18%, OR=0.41 for FPE; 5% vs 7%, OR=0.98 for mFPE).

CONCLUSIONS

Our findings suggest that approximately one-third of patients achieve FPE and around half of patients achieve mFPE, with equivalent results throughout thrombectomy techniques. FPE and mFPE are associated with better clinical outcomes.

Influence of first-pass effect on recanalization outcomes in the era of mechanical thrombectomy: a systemic review and meta-analysis

PURPOSE

This systematic review and meta-analysis summarized the current literature to compare the safety and efficacy between first-pass effect (FPE) and multiple-pass effect (MPE) for thrombectomy in treatment of acute ischemic stroke (AIS).

METHODS

Major databases were searched for studies which reported clinical outcomes regarding successful or complete recanalization after first pass of mechanical thrombectomy in AIS. The assessment of bias was performed using different scales. I² statistic was used to evaluate heterogeneity between reviewers. Subgroup, meta-regression, and sensitivity analyses were conducted to explore the source of heterogeneity. Visualization of funnel plots was used to evaluate publication bias.

RESULTS

A total of 9 studies were eligible for final analysis. For successful recanalization (mTICI 2b-3), favorable outcomes were seen in 49.7% (95% confidence interval (CI): 40.5-58.9%) and 34.7% (95% CI: 26.8-42.7%) of FPE and MPE patients, respectively. Mortality at 3 months was 13.8% (95% CI: 10.8-16.9%) and 26.0% (95% CI: 17.7-34.2%), respectively. For complete recanalization (mTICI 2c-3), proportion of favorable outcomes were 62.7% (95% CI: 51.2-74.2%) and 47.7% (95% CI: 37.4-58.0%) in FPE and MPE; mortality was seen in 11.5% (95% CI: 4.9-18.2%) and 17.0% (95% CI: 5.2-28.7%), respectively. For AIS with successful recanalization, FPE had more favorable outcome (odds ratio (OR): 1.85, 95% CI: 1.48-2.30; p < 0.01; I² = 0%) and lower mortality than MPE (OR: 0.58, 95% CI: 0.42-0.79; p = 0.001; I² = 61.9%). Similar results were seen in a subgroup analysis of patients with complete recanalization, with FPE having better outcome (OR: 1.79, 95% CI: 1.40-2.28; p < 0.01; I² = 0%) and lower mortality risk (OR: 0.61, 95% CI: 0.44-0.86; p = 0.005; I² = 0%) compared to MPE.

CONCLUSION

FPE is associated with better outcomes than MPE after achieving successful or complete recanalization.

Comparison of First-Pass Efficacy Among Four Mechanical Thrombectomy Techniques: A Single-Center Experience

BACKGROUND

First-pass efficacy (FPE) is an established marker of technical and clinical efficacy among mechanical thrombectomy (MT) techniques. It is unclear what the optimal approach is in achieving FPE. We present a single-center experience comparing rates of FPE among 2 MT techniques and evaluate the potential predictors of FPE among other outcomes.

METHODS

A single-center retrospective analysis was carried out of patients with consecutive large-vessel occlusion strokes (LVOS) of anterior circulation from September 2015 to April 2019 who underwent MT and for whom data were available on the status of FPE. Four MT techniques were identified: ADAPT (a direct first-pass aspiration), SrADAPT (stent retriever with aspiration), SRBG (stent retriever with balloon guide catheter), and STRAP (stent retriever-aspiration and proximal flow arrest). The primary outcome was FPE and secondary outcomes included the rate of successful reperfusion.

RESULTS

Among 226 patients with LVOS of the anterior circulation who underwent MT, data were available for 164 on FPE for the 4 MT techniques. SRBG was the most prevalent technique. No significant difference was found in rates of FPE among the 4 MT techniques (P = 0.332). No independent predictors of FPE were identified on multivariable analysis. STRAP had the highest rate of successful reperfusion compared with the other techniques (P = 0.049) and was the only independent predictor of that outcome (P = 0.027).

CONCLUSIONS

Among patients with LVOS of the anterior circulation, the rate of FPE did not differ among the 4 MT techniques. There were no predictors of FPE among the studied variables. STRAP was the only predictor of successful reperfusion.

Predictors of Successful First-Pass Thrombectomy with a Balloon Guide Catheter: Results of a Decision Tree Analysis

Complete recanalization after a single retrieval maneuver is an interventional goal in acute ischemic stroke and an independent factor for good clinical outcome. Anatomical biomarkers for predicting clot removal difficulties have not been comprehensively analyzed and await unused. We retrospectively evaluated 200 consecutive patients who suffered acute stroke and occlusion of the anterior circulation and were treated with mechanical thrombectomy through a balloon guide catheter (BGC). The primary objective was to evaluate the influence of carotid tortuosity and BGC positioning on the one-pass Modified Thrombolysis in Cerebral Infarction Scale (mTICI) 3 rate, and secondarily, the influence of communicating arteries on the angiographic results. After the first-pass mTICI 3, recanalization fell from 51 to 13%. The regression models and decision tree (supervised machine learning) results concurred: carotid tortuosity was the main constraint on efficacy, reducing the likelihood of mTICI 3 after one pass to 30%. BGC positioning was relevant only in carotid arteries without elongation: BGCs located in the distal internal carotid artery (ICA) had a 70% probability of complete recanalization after one pass, dropping to 43% if located in the proximal ICA. These findings demonstrate that first-pass mTICI 3 is influenced by anatomical and interventional factors capable of being anticipated, enabling the BGC technique to be adapted to patient’s anatomy to enhance effectivity.

First Pass Effect in Patients Treated With the Trevo Stent-Retriever: A TRACK Registry Study Analysis

Background and Objective: The first pass effect (FPE; achieving complete recanalization with a single thrombectomy device pass) has been shown to be associated with higher rates of good clinical outcomes in patients with acute ischemic stroke. Here, we investigate clinical and radiographic factors associated with FPE in a large U.S. post-marketing registry (TRACK, Trevo Stent-Retriever Acute Stroke).

Methods: We analyzed the TRACK database (multicenter registry of 634 patients from 23 centers from March 2013 through August 2015), which 609 patients were included in the final analysis. FPE was defined as a single pass/use of device, TICI 2c/3 recanalization, and no use of rescue therapy. Analysis of individual patient data from TRACK were performed to analyze clinical and radiographic characteristics associated with FPE as well-compared clinical outcomes defined as modified Rankin Scale (mRS) score at 30 and 90 days from hospital discharge to the non-FPE group.

Results: The rate of FPE in TRACK was 23% (140/609). There was no association between patient demographics and FPE, including age (p = 0.36), sex (p = 0.50), race (p = 0.50), location of occlusion (p = 0.26), baseline NIHSS (p = 0.62), or past medical history. There was no difference in the use of a balloon-guide catheter or general anesthesia (49 and 57% with FPE vs. 47 and 64%, p = 0.63 and p = 0.14, respectively). Clinical outcomes were significantly associated with FPE; 63 vs. 44% in non-FPE patients achieved mRS 0–2 at 90 days (p = 0.0004).

Conclusion: Our study showed that achieving complete recanalization with a single thrombectomy pass using the Trevo device was highly beneficial. The most common clinical factors that are used to determine eligibility for endovascular therapy, such as NIHSS severity, location of occlusion or patient age were not predictive of the ability to achieve FPE.