Outcome Following Mechanical Thrombectomy for Anterior Circulation Large Vessel Occlusion Stroke in the Elderly

Pooled data of randomized controlled trials investigating mechanical thrombectomy (MT) to treat anterior circulation large vessel occlusion have demonstrated safety and effectiveness across all age groups, including ≥ 80 years of age; however, only a few nonagenarians were in the ≥ 80 years subgroup. Therefore, the benefit of MT in nonagenarians is mostly unknown.

Two comprehensive stroke centers retrospectively reviewed all acute ischemic stroke patients who underwent MT for anterior circulation large vessel occlusion (LVO) stroke between February 2016 and August 2020. Revascularization TICI2b/3, symptomatic intracranial hemorrhage (ICH), and functional outcome using modified Rankin scale (mRS) were assessed for cases aged < 80 years, 80-89 years, and 90-99 years. Favorable functional outcome was defined as mRS 0-2 or reaching the prestroke mRS and moderate as mRS 0-3.

The final data set comprised a total of 736 cases. Of these, 466 aged < 80 years, 219 aged 80-89 years, and 51 aged 90-99 years. In nonagenarians, TICI 2b/3 revascularization was observed in 84.3% while symptomatic ICH was observed in 4%. These rates were similar to 80-89 years and < 80 years age groups. Favorable and moderate functional outcome as well as death rates differed significantly between nonagenarians and < 80 years (19.6%, 29.4%, 51.0% vs 47.9%, 60.7%, 18.7%, respectively, p < 0.001), but were similar between nonagenarians and octogenarians (29.7%, 38.8%, 38.8%, p = 0.112-0.211).

A moderate outcome among nonagenarians was observed in about 30%, while mortality rates were about 50%. Withholding mechanical thrombectomy does not appear justifiable, although the absolute treatment effect among nonagenarians remains unknown.