Al‐Bayati, Alhamza R

Background and importance Neurointervention is a very competitive specialty in the United States due to the limited number of training spots and the larger pool of applicants. The training standards are continuously updated to ensure solid training experiences. Factors affecting candidate(s) selection have not been fully established yet. Our study aims to investigate the factors influencing the selection process. Methods A 52-question survey was distributed to 93 program directors (PDs). The survey consisted of six categories: (a) Program characteristics, (b) Candidate demographics, (c) Educational credentials, (d) Personal traits, (e) Research and extracurricular activities, and (f) Overall final set of characteristics. The response rate was 59.1%. As per the programs’ characteristics, neurosurgery was the most involved specialty in running the training programs (69%). Regarding demographics, the need for visa sponsorship held the greatest prominence with a mean score of 5.9 [standard deviation (SD) 2.9]. For the educational credentials, being a graduate from a neurosurgical residency and the institution where the candidate's residency training is/was scored the highest [5.4 (SD = 2.9), 5.4 (SD = 2.5), respectively]. Regarding the personal traits, assessment by faculty members achieved the highest score [8.9 (SD = 1)]. In terms of research/extracurricular activities, fluency in English had the highest score [7.2 (SD = 1.9)] followed by peer-reviewed/PubMed-indexed publications [6.4 (SD = 2.2)]. Conclusion Our survey investigated the factors influencing the final decision when choosing the future neurointerventional trainee, including demographic, educational, research, and extracurricular activities, which might serve as valuable guidance for both applicants and programs to refine the selection process.

Background Balloon guide catheters (BGCs) can be used adjunctively during mechanical thrombectomy (MT) for acute ischemic stroke (AIS). Evaluating the potential economic impact associated with adjunctive BGC use is an important consideration for resource allocation. Methods Decision tree models were used to estimate the economic value of BGC use in MT through its impact on functional outcomes. Healthcare utilization cost estimates in the short- and long-term for patients with different 90-day mRS scores were analyzed for MT-only and MT + BGC scenarios. Deterministic (one-way) and probabilistic sensitivity analyses were performed to evaluate the robustness and uncertainty of model parameters. Results Per-patient index hospitalization cost was estimated at $65,260 for MT-only and $62,883 for MT + BGC scenarios. Per-patient one-year post-index hospitalization cost was estimated at $27,569 for MT-only and $24,830 for MT + BGC. MT + BGC had a total cost savings of $5117 compared with MT-only. Deterministic (one-way) sensitivity analysis demonstrated that cost saving per patient was most sensitive to the proportion of patients in the mRS 0–2 category in both MT + BGC and MT-only. In a probabilistic sensitivity analysis, mean per-patient costs for the index hospitalization were estimated at $63,737 for MT-only and $61,425 for MT + BGC. Mean per-patient cost estimates one-year post-index hospitalization was $27,445 for MT-only and $24,715 for MT + BGC. MT + BGC had a total cost savings of $5043 compared with MT-only. Conclusion Mechanical thrombectomy with adjunctive BGC use may reduce short-term and long-term patient costs due to improved functional outcomes when compared to MT treatment alone for AIS.

Background: Understanding clot composition may allow for better technical planning and improved outcomes in mechanical thrombectomy (MT). We sought to correlate clot composition with reperfusion outcomes in MT. Methods: Clinical, imaging, and clot data from patients enrolled in the STRIP Registry from September 2016 to September 2020 were analyzed. Samples were fixed in 10% phosphate-buffered formalin and stained with hematoxylin and eosin and Martius Scarlett Blue. Percent composition, richness, and gross appearance were evaluated. Outcome measures included the rate of First-Pass Effect (mTICI2c/3, FPE) and the number of device passes. Results: A total of 1430 patients (mean age, 68.4±13.5years; median [IQR] baseline NIHSS,17.2 [10.5-23]; IV-tPA use, 36%; Stent-Retrievers [SR], 27%; Contact Aspiration [CA], 27%; Combined SR + CA, 43%) were included. The median [IQR] number of passes was 1 [1-2]. FPE was achieved in 39.3% of the cases. There was no association between percent histological composition or clot richness and FPE in the overall population. However, the combined technique resulted in lower FPE rates for RBC-rich (P<0.0001), platelet-rich (P=0.003), and mixed (P<0.0001) clots. Fibrin-rich and platelet-rich clots required a higher number of passes compared to RBC-rich and mixed clots (median, 2 and 1.5 vs.1, respectively, P=0.02). CA displayed a trend towards a higher number of passes with fibrin-rich clots (2 vs.1, P=0.12). By gross appearance, mixed/heterogeneous clots had lower FPE rates than red and white clots. Conclusion: Despite the lack of correlation between clot histology and FPE in the overall population, our study adds to the growing body of evidence supporting the notion that clot composition influences reperfusion treatment strategy outcomes. Additional studies are needed.

Background Several animal studies have demonstrated that mechanical thrombectomy (MT) for acute ischemic stroke (AIS) may cause vessel wall injury (VWI). However, the histological changes in human cerebral arteries following MT are difficult to determine. Objective To investigate the occurrence of VWI during MT by histological and immunohistochemical evaluation of AIS clots. Methods As part of the multicenter STRIP registry, 277 clots from 237 patients were analyzed using Martius Scarlett Blue stain and immunohistochemistry for CD34 (endothelial cells) and smooth muscle actin (smooth muscle cells). Results MT devices used were aspiration catheters (100 cases), stentriever (101 cases), and both (36 cases). VWI was found in 33/277 clots (12%). There was no significant correlation between VWI and MT device. The degree of damage varied from grade I (mild intimal damage, 24 clots), to grade II (relevant intimal and subintimal damage, 3 clots), and III (severe injury, 6 clots). VWI clots contained significantly more erythrocytes (p=0.006*) and less platelets/other (p=0.005*) than non-VWI clots suggesting soft thrombus material. Thrombolysis correlated with a lower rate of VWI (p=0.04*). VWI cases showed a significantly higher number of passes (2 [1–4] vs 1 [1–3], p=0.028*) and poorer recanalization outcome (p=0.01*) than cases without VWI. Conclusions Histological markers of VWI were present in 12% of AIS thrombi, suggesting that VWI might be related to MT. VWI was associated with soft thrombus consistency, higher number of passes and poorer revascularization outcome. There was no significant correlation between VWI and MT device.

Background and aim Mechanical thrombectomy (MT) for large vessel occlusion often requires multiple passes to retrieve the entire thrombus load. In this multi-institutional study we sought to examine the composition of thrombus fragments retrieved with each pass during MT. Methods Patients who required multiple passes during thrombectomy were included. Histopathological evaluation of thrombus fragments retrieved from each pass was performed using Martius Scarlet Blue staining and the composition of each thrombus component including RBC, fibrin and platelet was determined using image analysis software. Results 154 patients underwent MT and 868 passes was performed which resulted in 263 thrombus fragments retrieval. The analysis of thrombus components per pass showed higher RBC, lower fibrin and platelet composition in the pass 1 and 2 when compared to pass 3 and passes 4 or more combined (P values <0.05). There were no significant differences between thrombus fragments retrieved in pass 1 and pass 2 in terms of RBC, WBC, fibrin, and platelet composition (P values >0.05). Similarly, when each composition of thrombus fragments retrieved in pass 3 and passes 4 or more combined were compared with each other, no significant difference was noted (P values >0.05). Conclusion Our findings confirm that thrombus fragments retrieved with each pass differed significantly in histological content. Fragments in the first passes were associated with lower fibrin and platelet composition compared to fragments retrieved in passes three and four or higher. Also, thrombus fragments retrieved after failed pass were associated with higher fibrin and platelet components.

Introduction: Evidence regarding the optimal acute antiplatelet strategies in emergent endovascular therapies is scarce, and practices varies institutionally. Ticagrelor, a P2Y3B inhibitor with a lower incidence of resistance, may be effective in achieving rapid platelet inhibition. We explore the safety and efficacy of emergent Ticagrelor use in patient undergoing neurointerventions. Methods: We reviewed our database for all consecutive patients from 2016 to 2019 who received emergent administration of Ticagrelor (within 30 minutes before or after) for neuro-interventional procedures. The primary outcome measure was the incidence of major systemic hemorrhages including symptomatic intracranial hemorrhage as well as intraprocedural and post-procedural thrombotic events. Results: 81 patients were analyzed (Mean age 62±11, 70% male, 73 undergoing interventions for ischemic strokes, 8 aneurysm patients undergoing embolization). Twenty (24.7%) patients received Ticagrelor pre-puncture, 28 (35%) during and 33 (41%) after closure. Median PRU achieved in 43 patients after excluding for concomitant use of GPIIbIIIa use was 54 [36-111]. Major bleeding occurred in 7/81 patients (9.2%) - 4 gastrointestinal bleeding and 3 symptomatic ICH. Eleven (14%) patients experienced intraprocedural occlusions. Five (6.2%) cases were complicated by post-procedural occlusions while on Ticagrelor, two of which were asymptomatic. Pre-procedural Ticagrelor was associated with less frequent administration of subsequent GPIIbIIIa (OR = 0.15, 95% CI (0.03-0.64), p=0.01), as well as shorter procedure duration (Spearman’s rho 0.409, p =0.001). The use of GPIIbIIIa plus Ticagrelor was associated with increased bleeding complications (0% vs. 14%; p =0.04) than in patients receiving Ticagrelor only. Bleeding was an independently predictive risk factor for death by 3 months (OR 7.18, 95% CI (1.33-38.8, p=0.02 or 43% vs. 9.5%; p=0.04) Conclusion: Early and emergent use of Ticagrelor, prior to endovascular procedure as early as within 30 minutes, may obviate the need for administration of GPIIbIIIa. Combined use of GPIIbIIa antithrombotics with Ticagrelor was associated with hemorrhagic complications, which could contribute to increased mortality.