Does MRI add value in selecting patients for thrombectomy beyond the 6 h window? A matched-control analysis

Area of Science:

• Neurology
• Interventional Radiology
• Public Health

Background:

• Debate exists on the necessity of advanced imaging for patient selection in extended time windows for mechanical thrombectomy.
• Current guidelines often recommend advanced imaging, potentially limiting access to treatment.

Purpose of the Study:

• To evaluate the impact of initial imaging modalities (NCCT ± CTA vs. MRI) on clinical outcomes for patients undergoing mechanical thrombectomy (MT) within the 6-24 hour window.
• To compare the efficacy and safety of different imaging selection methods in acute ischemic stroke patients.

Main Methods:

• Retrospective analysis of the prospective ANGEL-ACT registry (111 hospitals, Nov 2017-Mar 2019, China).
• Comparison of NCCT ± CTA versus MRI for patient selection in primary and guideline-like cohorts (DAWN/DEFUSE 3 criteria).
• Primary outcome: 90-day modified Rankin Scale (mRS); Safety outcomes: symptomatic intracranial hemorrhage (sICH), any ICH, 90-day mortality.

Main Results:

• No significant differences in 90-day mRS or safety outcomes (sICH, any ICH, 90-day mortality) were observed between NCCT ± CTA and MRI groups after covariate adjustment.
• Propensity score matching and mixed-effects logistic regression models yielded consistent results.

Conclusions:

• Mechanical thrombectomy in the extended window (6-24 hours) for anterior large vessel occlusion is potentially beneficial even without MRI selection.
• These findings suggest broader eligibility for MT in the extended window, but require validation through prospective randomized trials.