More than three passes of stent retriever is an independent predictor of parenchymal hematoma in acute ischemic stroke

Abstract

Introduction: Despite successful recanalization with mechanical thrombectomy (MT) for acute anterior ischemic stroke (AAIS), the number of passes may impact clinical outcome.We analyzed the impact of more than three MT passes (>3) in a trial that evaluated contact aspiration (CA) versus stent retriever (SR) as the first-line technique in AAIS.

Methods: We included patients with mTICI 2b/3 recanalization after MT for isolated intracranial occlusions. The primary outcome was the percentage of patients with a 90-day modified Rankin Scale (mRS)≤2. Secondary outcomes included overall distribution of 90-day mRS, parenchymal hematoma on 24 hours' brain imaging (PH), and 90-day mortality.

Results: Among the 281 patients included and even after adjustment on time to recanalization, significantly more patients with >3 passes had PH than patients with ≤3 passes in multivariate analysis (adjusted OR, 3.62; 95% CI, 1.55 to 8.44). When the analyses were stratified according to CA vs. SR, patients with >3 passes had a stronger risk of PH than patients with ≤3 passes, only in the SR first-line-treated group (adjusted OR, 9.24; 95% CI, 2.65 to 32.13) and not in the CA first-line-treated group (adjusted RR, 1.73; 95% CI, 0.57 to 5.19). A negative association of borderline significance (P=0.07) between >3 passes and favorable outcome was observed only in SR first-line-treated patients (adjusted OR, 0.33; 95% CI, 0.09 to 1.11).

Conclusions: After three passes of SR and unlike for three passes of CA, there is an increased risk of PH and a trend toward a worse clinical outcome.

Keywords: device; stroke; technique; thrombectomy.