Should Patients With Ischemic Stroke Be Transferred for Late-Window Endovascular Thrombectomy?

Patients with ischemic stroke with large-vessel occlusion in the anterior circulation who are transferred for late-window endovascular thrombectomy (EVT) have similar functional outcomes at 90 days to patients who were directly admitted to EVT-capable hospitals, according to study results published in JAMA Neurology.

Researchers performed a subanalysis of a prospective randomized phase 3 trial (DEFUSE 3; ClinicalTrials.gov identifier: NCT02586415) that enrolled patients with stroke and large-vessel anterior circulation occlusion and initial infarct volume of <70 mL (n=182) who were followed for up to 90 days. Patients also had mismatch ratio of ≥1.8, mismatch volume of ≥15 mL, and were treated within a 6- to 16-hour period from being well.

The investigators stratified patients into direct (ie, patients who directly presented to an EVT-capable study site [n=61]) and transfer (ie, patients who presented to an outside facility and to a study site for EVT [n=121]).

An ordinal evaluation of score distribution on the 90-day modified Rankin Scale score (mRS) was used to assess the primary outcome. Additional secondary outcomes included functional independence as examined with the 90-day mRS (0-2) and the median 24-hour and discharge National Institutes of Health Stroke Scale score.

Patients in the transfer group had a longer median time from last known well to arrival at the study site compared with direct patients (9.43 hours vs 9 hours, respectively).

In addition, transfer patients had more favorable median collateral profiles based on the hypoperfusion intensity ratio (0.35 [interquartile range (IQR), 0.18-0.47] vs 0.42 [IQR, 0.25-0.56]; P =.05).

In terms of changes in the 90-day mRS, no difference was observed between the direct group (odds ratio [OR] 2.9; 95% CI, 1.2-7.2; P =.01) and the transfer group (OR 2.6; 95% CI, 1.3-4.8; P =.009).

Individuals who received EVT had a higher functional recovery rate vs patients who received medical management in both the direct (44% vs 22%; OR 2.0; 95% CI, 0.9-4.4; P =.07) and transfer (45% vs 14%; OR, 3.1; 95% CI, 1.6-6.1; P <.001) groups.

Limitations of this analysis include its retrospective nature and the small number of patients in each group.

The researchers concluded that their findings indicate “transferring patients for late-window thrombectomy may be associated with substantial clinical benefits and should be encouraged.”

Reference

Sarraj A, Mlynash M, Savitz SI, et al. Outcomes of thrombectomy in transferred patients with ischemic stroke in the late window: a subanalysis from the DEFUSE 3 trial [published online February 7, 2019]. JAMA Neurol. doi:10.1001/jamaneurol.2019.0118