Abstract
Background
Criticism of clinical trials of endovascular therapy of acute ischemic stroke due to large vessel occlusion includes their lack of generalizability. We aimed to evaluate the impact of vessel tortuosity on the outcomes of large-bore and super-bore aspiration catheters in the Imperative Trial and to compare trial's selection of patients to a real-world setting.
Methods
Using baseline craniocervical angiography, we performed semi-automated analysis of various tortuosity characteristics. Comparison of tortuosity characteristics was made to a previously published cohort of 100 consecutive patients treated with thrombectomy (real-world cohort).
Results
Of the 249 Imperative Trial patients with anterior circulation strokes, 187 (89%) had complete tortuosity assessments from the aortic arch to the occlusion site. Tortuosity indexes for the common carotid, extracranial and intracranial internal carotid artery segments were similar for both cohorts (right side 0.18 ± 0.10, 0.17 ± 0.09, 0.45 ± 0.09 vs. 0.20 ± 0.09, 0.17 ± 0.09, 0.45 ± 0.09; left side: 0.12 ± 0.08, 0.19 ± 0.09, 0.44 ± 0.07 vs. 0.15 ± 0.08, 0.18 ± 0.08, 0.47 ± 0.07 in the Imperative Trial and in the real-world cohort, respectively). The proportion of patients with type 3 aortic arches was higher in the Imperative Trial than the real-word cohort (26% vs. 15%, p = .038).
Conclusions
Imperative trial patients treated with aspiration thrombectomy had similar vascular tortuosity characteristics compared to patients treated with thrombectomy in a real-world clinical setting. This confirms the generalizability of Imperative Trial findings to real-world clinical practice.
Keywords: Stroke, thrombectomy, aspiration, tortuosity, CTA
Introduction
Mechanical thrombectomy (MT) is an established first-line treatment strategy of patients with acute ischemic stroke (AIS) from large vessel occlusion (LVO). 1 Intraprocedural success of MT is primarily gauged by the degree of established reperfusion, as well as additional technical performance metrics, such as the time from arterial access to first and final passes before reperfusion is achieved, and MT procedure duration. 2
Primary aspiration using the ADAPT technique is a versatile approach to MT that is increasingly used by neurointerventionalists due to its simplicity and cost-effectiveness. 3 Highly trackable aspiration catheters including super-bore internal diameter catheters designed to improve clot ingestion have been evaluated in independent clinical trials as a new promising approach to facilitate arterial access and reperfusion rates. All of these technical factors are critical since they are known to influence clinical outcomes of MT.
In a real-world setting, MT procedures are normally performed outside of clinical trials. A study of over 23,000 patients treated with MT in the United States showed that only 1.8% underwent the procedure as a part of a clinical trial. 4 In a separate analysis of a prospective endovascular stroke registry from Germany, where inclusion criteria of several major landmark randomized trials of thrombectomy were applied, it was found that such trials would only select populations with the highest rates of good clinical outcomes. 5 Similar findings indicating a lack of generalizability of MT trials to clinical practice were voiced by others.6,7 Thus, legitimate concerns remain that the procedural and clinical data derived from such trails are not reflective of daily practice and operator experiences.
Extracranial arterial tortuosity has been shown to influence MT procedure duration and success in patients with AIS from LVO.8–12 Aortic arch variants, cervical carotid tortuosity, and several other anatomical features measured from baseline craniocervical imaging can be predictive of a challenging MT procedure.8,11 Limited knowledge is available on how arterial access and tortuosity influence the performance of aspiration thrombectomy devices specifically.
In this study, we aimed to evaluate the impact of vessel tortuosity on the technical and clinical outcomes of large-bore and super-bore aspiration catheters in the Imperative Trial and to compare anatomical characteristics of enrolled patients to the previously published data of consecutive patients treated with MT in a real-world setting.
Methods
Imperative trial design
The Imperative Trial was an FDA-approved Investigational Device Exemption study across 26 institutions in the United States to evaluate the clinical performance of the Zoom Reperfusion System, including the use of 0.088″ ID super-large bore aspiration catheters (Imperative Care, Inc., Campbell, CA, USA). The study protocol and consent were approved by the institutional review board at each participating center.
Patients who met the study's inclusion criteria were prospectively consented before groin puncture and treated between October 2021 and March 2024. In brief, patients age 18 and older, NIHSS 6 and above, baseline mRS 0-1, an Alberta Stroke Program Early CT Score (ASPECTS) ≥ 6 and occlusion of the intracranial internal carotid artery (ICA), middle cerebral artery (MCA) M1 or M2 segments, basilar, or vertebral arteries confirmed by computed tomography angiography (CTA) or magnetic resonance angiography (MRA) were eligible for the trial. In patients eligible for intravenous thrombolysis, thrombolytic therapy was administered prior to the initiation of aspiration. An independent core lab adjudicated radiographic baseline, procedural, and follow-up imaging studies. The primary efficacy endpoint of the trial was core lab adjudicated mTICI ≥2b, using the primary treatment modality (Zoom System only) within ≤3 passes, without additional therapies.
Image processing and calculation of tortuosity
Using baseline CTA or MRA studies, we performed semi-automated analysis of various tortuosity characteristics including the tortuosity index (TI), angle of curvature (AOC), and aortic arch type using the general methodology previously described by Mokin et al. 8 Tortuosity analysis was performed blinded to procedural or radiographic outcome data by an independent assessor (Jacobs Institute, Buffalo, NY) who was not involved in Imperative Trial design or enrollment. Anterior circulation stroke procedures were selected for analyses as the comparator real-world cohort only included analysis of anterior circulation tortuosity.
Baseline scans were uploaded into Mimics Version 26.0 (Materialise, Leuven, Belgium) and screened to include scans with both the pathway of interest and the highest number of slices for optimal resolution. The anatomy was filtered to remove any calcifications or non-clinical artifacts. Cases with low scan quality and/or image noise (such as due to a combination of insufficient contrast, inadequate Hounsfield unit differentiation, high levels of image noise or metal artifacts causing degradation of image clarity) or incomplete image sets (such as scans with varying slice thicknesses, which caused discontinuities in the slice stacks preventing the merging of slices into a coherent 3D structure) were excluded from analysis.
Centerlines were generated for each patient using a built-in tool in Mimics (Figure 1a). Each centerline began at the intersection of the aorta and brachiocephalic (right side) or common carotid (left side) artery to the respective right or left distal M1 based on the side of stroke treatment. TI (the ratio of the straight-line distance to the pathway along the centerline distance between two selected points) was measured across three segments: the aortic arch to the common carotid artery (CCA) bifurcation, the CCA bifurcation to the start of the petrous ICA, and the petrous ICA to the MCA bifurcation (Figure 1a).
Figure 1.
Image processing and semi-automated measurements of tortuosity. (a) An illustrative example of 3D reconstruction and tortuosity index (TI) calculated for the common carotid artery (CCA), extracranial internal carotid artery (ICA) and intracranial ICA segments. Here, bilateral TI measurements are shown. (b) Examples of type I, II, III and bovine arch anatomical variants. Dashed lines indicate the top of the arch and the level of the origin of the brachiocephalic artery. Solid lines correspond to the diameter of the left CCA. (c) Tortuosity index (TI) calculations for the CCA, extracranial and ICA artery segments from the Imperative Trial patients and previously published cohort of consecutive patients treated with thrombectomy in a real-world clinical setting (Mokin et al., 8 Figure 3 histogram data) are shown. Whiskers represent the normal range of TI variation (excluding outliers more than 1.5× the IQR from the median), asterisks the outlier datapoints, closed bars the IQR of variation, and the solid bars within the box mark the median.
The centerlines were exported as .txt files which include values at each control point of its 3D coordinates, normal/binormal/tangent vectors, and vessel best fit diameter. The total pathlength and AOC were calculated as a function of each of the centerline's 3D coordinates, plotted as a function of patient pathlength versus cumulative AOC.
The aortic arch type was classified based on previously described methodology by Alverne et al. 13 The top of the aortic arch apex and the origin of the brachiocephalic takeoff were identified. The offset distance between these two points was measured and used to classify the aortic arch types as follows: type I Arch (vertical distance from the origin of the brachiocephalic takeoff to the top of the arch less than one left CCA diameter), type II Arch (between 1 and 2 left CCA diameters), type III Arch (offset greater than two left CCA diameters) and bovine arch anatomy (left CCA originating from the brachiocephalic trunk; Figure 1b). A case example of aspiration thrombectomy and semi-automated measurements of tortuosity is shown in Figure 2.
Figure 2.
Case example of aspiration thrombectomy and semi-automated measurements of tortuosity. (a) Craniocervical computed tomography angiography showing right middle cerebral artery M1 occlusion. The patient had type III arch variant. Note severe tortuosity of the cervical carotid segment. (b) Aspiration thrombectomy was performed and with a single pass, complete successful reperfusion was achieved. (c) 3D reconstruction for semi-automated measurements of tortuosity index were used for data analysis.
Data analysis
We compared the baseline characteristics and efficacy results for the anterior circulation stroke patients treated in the Imperative Trial that were included in the tortuosity analysis against the subset of patients that were excluded to determine if missing tortuosity data could bias the conclusions drawn from the analysis. We focused on procedure time metrics and site assessed reperfusion success as these endpoints best represent the experience of the study operators and the real-world decision-making process for when to conclude a procedure. Means were compared using a two-sample t test, medians using a Mann‒Whitney test, and rates using a Fisher's exact rest. Tortuosity characteristics from the Imperative Trial were also compared to the previously published analysis of vascular tortuosity characteristics of 100 consecutive anterior circulation LVO patients treated with thrombectomy. 8 In that study, TI and angulations of catheter pathways were measured similarly to the methodology of our imaging analysis. Patient-level data and sample sizes for the tortuosity indices were not available for this publication, so valid statistical comparisons were not possible for these metrics. The histogram data presented in that publication was used to estimate the patient-level data (Figure 1c) and we compared the descriptive statistics that were provided for the left and right-side TI (Table 2).
Table 2.
Tortuosity index and aortic arch comparison to prior literature.
| Characteristic | Imperative trial | Mokin et al. |
|---|---|---|
| Right side tortuosity (average ± SD) CCA segment Extracranial ICA Intracranial ICA |
0.18 ± 0.10 0.17 ± 0.09 0.45 ± 0.09 |
0.20 ± 0.09 0.17 ± 0.09 0.45 ± 0.09 |
| Left side tortuosity (average ± SD) CCA Segment Extracranial ICA Intracranial ICA |
0.12 ± 0.08 0.19 ± 0.09 0.44 ± 0.07 |
0.15 ± 0.08 0.18 ± 0.08 0.47 ± 0.07 |
| Arch type, % (n/N) Type 1 Type 2 Type 3 |
40 (79/196) 34 (66/196) 26 (51/196) |
44 (44/100) 41 (41/100) 15 (15/100) |
| Bovine arch, % (n/N) | 16 (32/196) | 25 (25/100) |
| Sum of angles of curvature (average ± SD) | 1491 ± 331 degrees | N/A |
Abbreviations: CCA: common carotid artery; ICA: internal carotid artery; SD: standard deviation.
Spearman's correlation was used to examine the association between TI, AOC, baseline characteristics (age, height), procedure time metrics, and other continuous variables. Linear regression analyses were completed to evaluate the relationship between TI and AOC as a function of categorical baseline and procedure characteristics. Binary logistic regression analyses were completed to evaluate the relationships between procedural outcomes using the mTICI scale and functional outcomes (modified Rankin scale [mRS] 0–2 at 3 months) as a function of TI and AOC. One-way ANOVA and Mood's median tests were used to compare rates and continuous variable outcomes, respectively, between the three aortic arch types.
Statistical analyses were performed using Minitab 22.2.0 statistical software (Minitab Inc., State College, PA). Aggregate data, including patient demographics, baseline characteristics, effectiveness, and clinical outcomes were summarized by descriptive statistics. Data were presented as mean (standard deviation), median (IQR), and percentage (counts). Mean and standard deviation were generally reported for continuous variables. Medians and interquartile ranges (IQR) were reported for discrete variables. All analyses were completed based on available data without imputation for missing data points.
Results
Vessel segmentation and arch anatomy analyses were completed for 92% (209/249) of the Imperative Trial patients with anterior circulation strokes, with 89% (187/209) having complete tortuosity assessments from the aortic arch to the MCA M1 or the carotid occlusion location. There were no notable differences in baseline characteristics or efficacy results (Table 1) between the 209 patients included in the tortuosity analysis and the 40 patients with anterior circulation strokes whose baseline CTAs were missing or unsuitable for analysis. One patient included in the analysis had a bilateral stroke in the right M1 and left ICA, with each side assessed separately for tortuosity and reperfusion success, resulting in a total sample size of 210.
Table 1.
Baseline characteristics and procedural outcomes in imperative trial anterior circulation stroke population.
| Characteristic | All anterior circulation strokes | p | |
|---|---|---|---|
| Excluded patients | Tortuosity analysis dataset | ||
| Female, % (n/N) | 45 (18/40) | 50 (105/209) | .606 |
| Age, median [IQR] | 66 years [58–80 years] | 70 years [60–79 years] | .635 |
| Height, average ± SD [min–max] |
168 ± 9>cm [147–188 cm] |
170 ± 11>cm [137–193 cm] |
.135 |
| Hypertension, % (n/N) | 85 (34/40) | 74 (155/209) | .162 |
| Diabetes, % (n/N) | 28 (11/40) | 25 (53/209) | .844 |
| Smoking history, % (n/N) Current or quit <6 months Quit >6 months Never Unknown |
15 (6/40) 25 (10/40) 40 (16/40) 20 (8/40) |
20 (41/209) 24 (51/209) 48 (101/209) 8 (16/209) |
.660 >.999 .389 N/A |
| TLKW to groin puncture, median [IQR] | 2.8>h [2.3–4.0>h] |
3.0>h [2.3–4.3>h] |
.874 |
| Received IV thrombolytics, % (n/N) | 58 (23/40) | 47 (99/209) | .301 |
| Baseline NIHSS, median [IQR] | 15 [–, 11, 21] |
15 [–, 11, 20] |
.376 |
| ASPECTS, average ± SD | 8.7 ± 1.9 | 8.8 ± 1.7 | .813 |
| General anesthesia, % (n/N) | 50 (20/40) | 35 (73/209) | .077 |
| Right side occlusion, % (n/N) | 40 (16/40) | 52 (109/210) | .227 |
| Treated occlusion location, % (n/N) ICA MCA-M1 MCA-M2 MCA-M3 MCA-M1 + ACA Bilateral (right M1 + Left ICA) |
23 (9/40) 53 (21/40) 25 (10/40) 0.0 (0/40) 0.0 (0/40) 0.0 (0/40) |
11 (24/209) 61 (127/209) 26 (55/209) 0.5 (1/209) 0.5 (1/209) 0.5 (1/209) |
.074 .381 >.999 >.999 >.999 >.999 |
| Endpoints | |||
| Successful ICA access, % (n/N) | 100 (40/40) | 100 (210/210) | >.999 |
| Successful clot access w/zoom, % (n/N) | 100 (40/40) | 99 (207/210) | >.999 |
| Access site conversions, % (n/N) | 0.0 (0/40) | 1.0 (2/210) | >.999 |
| Total number of passes, % (n/N) 1 2 3 4 ≥5 |
55 (22/40) 18 (7/40) 10 (4/40) 10 (4/40) 7.5 (3/40) |
52 (110/210) 25 (53/210) 10 (22/210) 5.7 (12/210) 6.2 (13/210) |
.863 .419 >.999 .297 .727 |
| Core lab adjudicated mTICI ≥2b within ≤3 passes of the study device | 85 (34/40) | 82 (171/208) | .821 |
| Site assessed reperfusion success | |||
| Final mTICI ≥2b, % (n/N) | 100 (40/40) | 97 (204/210) | .593 |
| Final mTICI ≥2c, % (n/N) | 73 (29/40) | 76 (160/210) | .688 |
| Puncture to supra-aortic position, median [IQR] | 7>min [4–11>min] |
7>min [4–10>min] |
.339 |
| Puncture to target occlusion, median [IQR] | 12>min [9–21>min] |
11>min [8–17>min] |
.114 |
| Puncture to mTICI ≥2b, median [IQR] | 19>min [14–39>min] |
20>min [13–30>min] |
.489 |
| Puncture to mTICI ≥2c, median [IQR] | 20>min [15–41>min] |
21>min [14–34>min] |
.500 |
| Puncture to procedure completion, median [IQR] | 25>min [16–54>min] |
23>min [15–39>min] |
.310 |
| Clinical outcomes | |||
| 24 hour NIHSS, median [IQR] | 4 [–, 1, 15] | 5 [–, 2, 14] | .985 |
| 90 Day mRS 0–2, % (n/N) | 54 (19/35) | 53 (106/199) | >.999 |
Abbreviations: ACA: anterior cerebral artery; ASPECTS: Alberta Stroke Program Early Computed Tomography Score; ICA: internal carotid artery; IQR: interquartile range; IV: intravenous; MCA: middle cerebral artery; mRS: modified Rankin Score; mTICI: modified thrombolysis in cerebral infarction; NIHSS: National Institutes of Health Stroke Scale; SD: standard deviation; TLKW: time last known well.
Comparing analysis from the Imperative Care trial with the previously published real-world cohort of 100 consecutive anterior circulation patients treated with thrombectomy (Mokin et al. 8 ) showed similar medians for the TI of the CCA, extracranial ICA, and intracranial ICA segments (Figure 1c). There were no significant correlations between the occlusion side and tortuosity within the Imperative Trial (Supplementary Table 2), though numerically lower CCA tortuosity was noted for left-sided strokes (Table 2) which is similar to findings from the real-world cohort.
The proportion of patients with Type 3 aortic arches was significantly higher and the proportion of bovine arches was numerically lower in the Imperative Trial than the real-world cohort but not statistically significant (26% vs. 15%, p = .038 and 16% vs. 25%, p = .087, respectively; Table 2).
There were no strong correlations observed between the assessed baseline characteristics and vessel tortuosity (Supplementary Tables 1–3). For continuous characteristics, we observed a moderate and statistically significant correlation between age and more tortuosity in the CCA (rs = .34, p < .001) and extracranial ICA (rs = .34, p < .001). For categorical characteristics, we observed weak statistically significant correlations between higher CCA tortuosity in female patients (r2 = 10%, p < 0.001) and hypertensive patients (r2 = 6.8%, p < .001). Female patients were also noted to have a numerically higher rate of type 3 aortic arches than male patients (30% vs. 18%, p = .053). Lower CCA tortuosity was observed in patients who were current smokers (r2 = 4.9%, p = .002). Patients with ICA occlusions had lower intracranial ICA tortuosity (r2 = 7.3%, p < .001), which is likely explained by ICA occlusions inherently excluding the tortuosity distal to the occlusion location.
There were also no strong correlations observed between procedure outcomes, clinical outcomes, and vessel tortuosity (Supplementary Tables 1–3). There were weak statistically significant correlations between higher extracranial ICA tortuosity and increased procedure times (Table 3). A similar weak association between increased procedure times and the sum of the angles of curvature was also observed (Supplementary Table 1). CCA and Intracranial ICA tortuosity generally had negligible or no correlations with the procedure time metrics, though a weak association was observed between higher intracranial ICA tortuosity and fewer passes being required to complete the procedure (rs = ‒0.14, p = .042).
Table 3.
Correlation between supra aortic vessel tortuosity and procedure times.
| Characteristic | CCA tortuosity | Extracranial ICA tortuosity | Intracranial ICA tortuosity | |||
|---|---|---|---|---|---|---|
| rs | p | rs | p | rs | p | |
| Puncture to supra-aortic position | −0.07 | .332 | −0.02 | .169 | 0.09 | .348 |
| Puncture to target occlusion | 0.05 | .486 | 0.23 | .001 | 0.18 | .445 |
| Puncture to mTICI ≥2b | 0.01 | .879 | 0.22 | .002 | 0.07 | .301 |
| Puncture to mTICI ≥2c | −0.03 | .724 | 0.19 | .008 | 0.04 | .575 |
| Puncture to procedure completion | 0.00 | .983 | 0.17 | .014 | 0.02 | .805 |
Abbreviations: mTICI: modified thrombolysis in cerebral infarction; rs: Spearman's correlation.
A significant difference was observed when comparing the median time to achieve supra-aortic access between patients with Type 1, Type 2, and Type 3 aortic arches (Supplementary Table 5). There were no significant differences in the other assessed procedure times or outcomes, though trends towards longer procedure times and lower rates of reperfusion success were associated with Type 3 aortic arches.
Discussion
Clinicians frequently voice criticism of clinical trials due to their lack of generalizability. In the field of ischemic stroke, this applies to trials of stroke thrombectomy,4,6,14 intravenous thrombolysis, 15 and post-stroke rehabilitation.16,17 Ensuring that trial populations are representative of real-world patient demographics and anatomical variabilities is crucial for the applicability of study findings to broader clinical practice. 18 Our study is a novel contribution in that regard, providing a first of its kind comprehensive assessment of vascular anatomy in a prospective thrombectomy trial cohort that lead to a 510(k) clearance and highlighting the importance of considering anatomical factors to ensure generalizability of the trial results to real-world stroke population.
Our findings reinforce the critical role of aortic arch type and craniocervical arterial tortuosity in determining procedural efficiency during MT. 13 The time required to achieve supra-aortic access varied significantly among patients with different aortic arch types, with Type 3 arches being associated with longer times. “Obtaining access”—a jargon that represents steps required to reach the target arterial occlusion with a catheter can substantially delay or even preclude successful recanalization. 13 While procedure time metrics were not significantly different among arch types, trends toward longer procedural durations and lower rates of reperfusion success in patients with Type 3 arches were observed in our study. This aligns with prior literature indicating that increased vessel tortuosity can pose technical challenges for neurointerventional procedures. 13 We also found a higher prevalence of Type 3 arches and more tortuous anatomy between the arch and CCA in female subjects, supporting that a balanced representation of both genders is important to ensure generalizability of study results.
Interestingly, while we observed a weak association between increased extracranial ICA tortuosity and longer procedure times, intracranial ICA tortuosity was weakly correlated with fewer passes to achieve recanalization. This counterintuitive finding may be related to the higher prevalence of ICA occlusions and an associated larger clot burden among the patients with lower intracranial tortuosity indices. Further research is necessary to elucidate the mechanistic underpinnings of these associations and to determine whether specific device modifications or procedural adaptations could mitigate the impact of extracranial tortuosity and ICA occlusions on thrombectomy outcomes.
A notable aspect of our study is the use of a semi-automated methodology for tortuosity measurement, reducing operator subjectivity and ensuring consistency in vessel segmentation and tortuosity assessments. This approach enhances data reliability and circumvents the need for inter-rater variability assessments, a common concern in studies relying on manual anatomical evaluations. Analogous to the gold standard of independent core laboratory adjudication of imaging data in modern MT trials, our methodology represents an objective and reproducible means of quantifying anatomical complexity in neurovascular research. Additionally, obtaining prospective consent and enrolling patients before groin puncture could mitigate concerns about selection bias that occurs when patients are consented or enrolled after obtaining supra-aortic access, ensuring that trial participants are representative of the real-world population. Future studies should consider incorporating similar automated or semi-automated analytical techniques to enhance comparability across different trial cohorts.
Despite its strengths, our study has certain limitations. The real-world comparator cohort was derived from a single institution and the patients in that cohort were treated during a different time period than the Imperative Trial, which may introduce confounding factors related to evolving procedural techniques and device advancements. Additionally, we did not have access to individual patient data from the real-world cohort, limiting our ability to more robustly compare baseline characteristics and procedural outcomes. A more up-to-date multi-center real-world cohort of consecutive patients with LVO stroke treated with MT at multiple sites would prove more beneficial for future research.
Conclusion
Imperative Trial patients treated with aspiration thrombectomy had anatomical characteristics, including aortic arch anatomy and craniocervical tortuosity, similar to the patients treated with MT in a real-world clinical setting. This confirms the generalizability of Imperative Trial findings to real-world clinical practice. Incorporating semi-automated analysis of vessel tortuosity represents an unbiased way of evaluating anatomical features of enrolled patients, which may help improve the accuracy of comparing stroke trial outcomes in the future.
Supplemental Material
Supplemental material, sj-docx-1-ine-10.1177_15910199251359089 for Semi-automated tortuosity measurements confirm generalizability of IMPERATIVE trial results to real-world patients with acute ischemic stroke undergoing thrombectomy by Maxim Mokin, William J Mack, Raul G Nogueira, Jonathan A Grossberg, Shahram Majidi, Dana Tomalty, Jan Vargas, Brett L Cucchiara, Kenneth V Snyder, Justin R Mascitelli, Victoria Parada, Hakeem J Shakir, David Rosenbaum-Halevi, Nima Aghaebrahim, Dan Hoit, Benjamin Yim, Matthew S Tenser, Alhamza R Al-Bayati, James M Milburn, Shahid M Nimjee, Neil Haranhalli, Michael Nahhas, Darryn I Shaff, Kennith F Layton, Narlin B Beaty, Robert M Starke, Harris Hawk, Diogo C Haussen, Aqueel Pabaney, Christopher P Kellner and Reade A De Leacy in Interventional Neuroradiology
Acknowledgments
We are grateful to Yousef Akkad, Adam Sparks, and Jillian Bogard from the Jacobs Institute for their technical and analytical support in tortuosity assessment. We dedicate this work to the memory of Dr Justin Singer, whose contributions to stroke thrombectomy have left a lasting impact on the field of neurosurgery. His dedication to advancing patient care, mentoring future generations, and unwavering commitment to excellence continue to inspire us.
Footnotes
Declaration of conflicting interests: The authors declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: M. Mokin: Grant: NIH; Consultant: Balt USA, Canon Medical, Imperative Care, J&J, Medtronic, MicroVention, Rapid Pulse; Stock: Bendit Technology, Borvo Medical, Brain Q, Endostream, QAS.AI, Quantanosis.AI, Radical Catheter Technologies, Serenity Medical, Sim&Cure, Synchrone, VICIS; W. Mack: Consultant: Egret, Imperative Care, Integra LifeSciences, Q’Apel, Rebound Therapeutics, Spartan Micro, Stream Biomedical, Stryker, Viseon; Stock: Borvo, Cerebrotech, Egret, Endostream, Q’Apel, Radical Catheters, Rebound Therapeutics, Spartan Micro, Stream Biomedical, Vastrax, Viseon; Raul G. Nogueira: Consultant: Stryker, Cerenovus, Medtronic, Phenox, Anaconda, Genentech, Biogen, Prolong Pharmaceuticals, Imperative Care; Stock: Brainomix, Viz-AI, Corindus Vascular Robotics, Vesalio, Ceretrieve, Astrocyte, Cerebrotech; Jonathan A. Grossberg: Grant: Emory Medical Care Foundation, Emory Neurosurgery Catalyst, Georgia Research Alliance, National Institute of Neurological Disorders and Stroke, Uniformed Services University-Surgical Critical Care Initiative; Consultant: Cognition, Imperative Care, NTI, Route 92; Shahram Majidi: Consultant: DePuy Synthes, Imperative Care, Medical Device Business Services, Rapid Medical; Dana Tomalty: Consultant: Imperative Care; Payment or honoraria for lectures, presentations, speakers’ bureaus, manuscript writing, or educational event: Inari Medical; Jan Vargas: Consultant: Viz.AI, Imperative Care, Precision Neuro, Q’Apel, Medtronic and Microvention; Stock: Viz.AI, Imperative Care, Borvo, Radical, Synchron; Brett L. Cucchiara: None; Kenneth V. Snyder: Consultant: Boston Scientific, Canon Medical Systems, MicroVention, Medtronic, Stryker; Payment or honoraria for lectures, presentations, speakers’ bureaus, manuscript writing, or educational event: Canon Medical Systems USA Inc; Stock or stock options: Boston Scientific, Access Closure, Niagara Gorge Medical; Justin R. Mascitelli 1 : Consultant: Stryker; Victoria Parada: None; Hakeem J. Shakir: Consultant: Imperative Care, Q’Apel Medical, Stryker; David Rosenbaum-Halevi: None; Nima Aghaebrahim: Payment or honoraria for lectures, presentations, speakers’ bureaus, manuscript writing, or educational event: Penumbra; Dan Hoit: Consultant: Imperative Care, Stryker; Payment or honoraria for lectures, presentations, speakers’ bureaus, manuscript writing, or educational event: Medtronic, MicroVention; Benjamin Yim: Consultant: Imperative Care, Q’Apel Medical; Matthew S. Tenser: None; Alhamza R. Al-Bayati: Consultant: Medical Device Business Services, Stryker; James M. Milburn: Consultant: Imperative Care, MicroVention; Shahid M. Nimjee: Consultant: Medical Device Business Services, Baskin Biosciences; Payment or honoraria for lectures, presentations, speakers’ bureaus, manuscript writing, or educational event: Medtronic; Neil Haranhalli: None; Sunil A. Sheth: Consultant: Imperative Care, Viz.AI; Payment or honoraria for lectures, presentations, speakers’ bureaus, manuscript writing, or educational event: Penumbra; Darryn I. Shaff : None; Kennith F. Layton : Consultant: Stryker; Narlin B. Beaty: Consultant: Stryker; Payment or honoraria for lectures, presentations, speakers’ bureaus, manuscript writing, or educational event: AstraZeneca; Robert M. Starke: Payment or honoraria for lectures, presentations, speakers’ bureaus, manuscript writing, or educational event: Medtronic, Penumbra; Harris Hawk: None; Diogo C. Haussen: Consultant: Chiesi USA, DePuy Synthes, Stryker; Aqueel Pabane: None; Christopher P. Kellner 5 : Consultant: Integra LifeSciences; Grant: Cerenovus, Medtronic; Reade A. De Leac: Consultant: Hyprevention, Imperative Care, J&J, Medical Device Business Services, Scientia Vascular, Stryker; Stock: Endostream, Q’Apel, Spartan Micro, Synchron, Van Vascular, Vastrax.
Research ethics approval: WCG IRB approved the study (#20192521).
Data sharing statement: Data are available upon reasonable request. Requests for data availability should be addressed to Imperative Trial principal investigators.
Funding: The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported by Imperative Care, Inc.
Contribution statement: MM, WJM, RDL, and RN contributed to study concept and design. MM wrote the manuscript. All authors contributed to data collection. MM contributed to data analysis. All authors edited the manuscript and approved the final version.
ORCID iDs: Maxim Mokin https://orcid.org/0000-0003-4270-8667
Jonathan A Grossberg https://orcid.org/0000-0002-1152-8826
Hakeem J Shakir https://orcid.org/0000-0003-4234-340X
Alhamza R Al-Bayati https://orcid.org/0000-0001-8103-1930
Michael Nahhas https://orcid.org/0000-0001-8198-7676
Supplemental material: Supplemental material for this article is available online.
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Associated Data
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Supplementary Materials
Supplemental material, sj-docx-1-ine-10.1177_15910199251359089 for Semi-automated tortuosity measurements confirm generalizability of IMPERATIVE trial results to real-world patients with acute ischemic stroke undergoing thrombectomy by Maxim Mokin, William J Mack, Raul G Nogueira, Jonathan A Grossberg, Shahram Majidi, Dana Tomalty, Jan Vargas, Brett L Cucchiara, Kenneth V Snyder, Justin R Mascitelli, Victoria Parada, Hakeem J Shakir, David Rosenbaum-Halevi, Nima Aghaebrahim, Dan Hoit, Benjamin Yim, Matthew S Tenser, Alhamza R Al-Bayati, James M Milburn, Shahid M Nimjee, Neil Haranhalli, Michael Nahhas, Darryn I Shaff, Kennith F Layton, Narlin B Beaty, Robert M Starke, Harris Hawk, Diogo C Haussen, Aqueel Pabaney, Christopher P Kellner and Reade A De Leacy in Interventional Neuroradiology