Clot Burden Score and Early Ischemia Predict Intracranial Hemorrhage following Endovascular Therapy

V. Yogendrakumar; F. Al-Ajlan; M. Najm; J. Puig; A. Calleja; S.-I. Sohn; S.H. Ahn; R. Mikulik; N. Asdaghi; T.S. Field; A. Jin; T. Asil; J.-M. Boulanger; M.D. Hill; A.M. Demchuk; B.K. Menon; D. Dowlatshahi

doi:10.3174/ajnr.A6009

Abstract

BACKGROUND AND PURPOSE: Intracranial hemorrhage is a known complication following endovascular thrombectomy. The radiologic characteristics of a CT scan may assist with hemorrhage risk stratification. We assessed the radiologic predictors of intracranial hemorrhage following endovascular therapy using data from the INTERRSeCT (Identifying New Approaches to Optimize Thrombus Characterization for Predicting Early Recanalization and Reperfusion With IV Alteplase and Other Treatments Using Serial CT Angiography) study.

MATERIALS AND METHODS: Patients undergoing endovascular therapy underwent baseline imaging, postprocedural angiography, and 24-hour follow-up imaging. The primary outcome was any intracranial hemorrhage observed on follow-up imaging. The secondary outcome was symptomatic hemorrhage. We assessed the relationship between hemorrhage occurrence and baseline patient characteristics, clinical course, and imaging factors: baseline ASPECTS, thrombus location, residual flow grade, collateralization, and clot burden score. Multivariable logistic regression with backward selection was used to adjust for relevant covariates.

RESULTS: Of the 199 enrolled patients who met the inclusion criteria, 46 (23%) had an intracranial hemorrhage at 24 hours. On multivariable analysis, postprocedural hemorrhage was associated with pretreatment ASPECTS (OR, 1.56 per point lost; 95% CI, 1.12–2.15), clot burden score (OR, 1.19 per point lost; 95% CI, 1.03–1.38), and ICA thrombus location (OR, 3.10; 95% CI, 1.07–8.91). In post hoc analysis, clot burden scores of ≤3 (sensitivity, 41%; specificity, 82%; OR, 3.12; 95% CI, 1.36–7.15) and pretreatment ASPECTS ≤ 7 (sensitivity, 48%; specificity, 82%; OR, 3.17; 95% CI, 1.35–7.45) robustly predicted hemorrhage. Residual flow grade and collateralization were not associated with hemorrhage occurrence. Symptomatic hemorrhage was observed in 4 patients.

CONCLUSIONS: Radiologic factors, early ischemia on CT, and increased CTA clot burden are associated with an increased risk of intracranial hemorrhage in patients undergoing endovascular therapy.

ABBREVIATIONS:

aOR: adjusted OR
CBS: clot burden score
EVT: endovascular therapy
ICH: intracranial hemorrhage

Footnotes

Disclosures: Robert Mikulik—RELATED: Grant: Project No. LQ1605 from the National Program of Sustainability II and the project of the International Clinical Research Center of St. Anne's University Hospital in Brno No. CZ.1.05/1.1.00/02.0123 (Operační program Výzkum a vývoj pro inovace).* Thalia S. Field—RELATED: Grant: Canadian Institutes of Health Research operating funds, Comments: The research program of the Vancouver Stroke Program received a per-patient payment to offset the cost of research nurse time and non-standard-of-care neuroimaging for the INTERRSeCT study*; UNRELATED: Consultancy: Bayer Canada, Pfizer-Bristol-Myers Squibb, Servier Laboratories, Comments: Advisory Board honoraria; Grants/Grants Pending: Canadian Institutes of Health Research, Heart and Stroke Foundation of Canada, Canadian Stroke Consortium, Bayer Canada, Boehringer-Ingelheim, Comments: Canadian Institutes of Health Research, Heart and Stroke Foundation of Canada, Canadian Stroke Consortium operating funds, Boehringer Canada operating funds, and Bayer Canada in-kind study medication*; Payment for Lectures Including Service on Speakers Bureaus: Bayer Canada, Pfizer-Bristol-Myers Squibb, Servier Laboratories, Boehringer-Ingelheim, Comments: Speakers Bureau honoraria from Bayer Canada, Pfizer-Bristol-Myers Squibb, Servier Laboratories, and Boehringer-Ingelheim Canada. Jean-Martin Boulanger—UNRELATED: Consultancy: Novartis, Bayer, Pfizer, Comments: conferences and Advisory Boards. Michael D. Hill—RELATED: Grant: Canadian Institutes of Health Research, Comments: grant to the University of Calgary. The principal Investigator was Dr A.M. Demchuk. I was a coinvestigator on the grant*; UNRELATED: Board Membership: Canadian Neuroscience Federation, Comments: not-for-profit entity; Consultancy: Boehringer-Ingelheim; Grants/Grants Pending: Medtronic, Stryker, Bayer Canada, Boehringer-Ingelheim, NoNO Inc, Canadian Institutes of Health Research, Alberta Innovates, British Heart Foundation, Comments: grants for ongoing studies; Stock/Stock Options: Calgary Scientific Inc, Comments: stock ownership. Andrew M. Demchuk—RELATED: Consulting Fee or Honorarium: Medtronic. Bijoy K. Menon—RELATED: Grant: Canadian Institutes of Health Research, Comments: operating grant.* Dar Dowlatshahi—UNRELATED: Consultancy: ApoPharma, Bayer; Payment for Lectures Including Service on Speakers Bureaus: Bristol-Myers Squibb. *Money paid to the institution.
INTERRSeCT was originally funded by an operating grant from the Canadian Institutes of Health Research. Dr Dowlatshahi was funded by a University of Ottawa Department of Medicine Clinician-Scientist Research Chair award and a Heart and Stroke Foundation of Canada New Investigator Award. Dr Yogendrakumar is supported by the Queen Elizabeth II Graduate Scholarship for Science and Technology and the Canadian Institutes of Health Research Banting and Best Graduate Scholarship. Dr Mikulik was supported by No. LQ1605 from the National Program of Sustainability II (MEYS CR) and by The International Clinical Research Center of St. Anne's University Hospital in Brno No. CZ.1.05/1.1.00/02.0123 (Operační program Výzkum a vývoj pro inovace).