Benefits of First Pass Recanalization by Initial Infarct Burden for Basilar Artery Strokes.

Background and aims: Achieving a first pass recanalization (FPR) improves clinical outcomes in patients with basilar artery strokes, but its association with initial infarct burden is unknown. We aimed to study the benefits of FPR for basilar artery strokes by initial infarct burden using the Posterior Circulation Alberta Stroke Program Early CT score (pc-ASPECTS).

Methods: We retrospectively analyzed the prospective multicentric Endovascular Treatment of Ischemic Stroke registry and included 194 patients diagnosed with an acute basilar artery occlusion who were treated with thrombectomy. Our primary outcome was a modified Rankin Scale (mRS) of 0-3 at 90 days, and our secondary outcomes were an mRS of 4-6 and mortality. We compared the 90-day clinical outcomes of achieving an FPR versus multiple thrombectomy passes based on patients' initial infarct size on pretreatment MRI: small (pc-ASPECTS = 9-10), medium (pc-ASPECTS = 6-8) and large (pc-ASPECTS <6).

Results: Patients with a medium or large infarct size had significantly better outcomes (mRS 0-3 at 3 months) if FPR was achieved than if multiple passes were required (RR = 1.61, 95% CI: 1.16, 2.24; p-value = 0.005; and RR = 3.41, 95% CI: 1.54-7.57; p-value = 0.003, respectively). No similar difference was seen among patients with small infarcts. Achieving an FPR was also associated with a significantly lower mortality risk among patients with a moderate infarct size (RR = 0.36, 95% CI: 0.17-0.79; p-value = 0.010) but not with those with small or large infarcts.

Conclusions: Achieving an FPR significantly improves clinical outcomes in acute stroke patients with basilar artery occlusions undergoing thrombectomy when their infarcts are medium or large. Ongoing research to develop surgical techniques to achieve FPR is crucial to improving patients' prognoses.