Thrombectomy tied to better functional outcomes in large ischaemic stroke patients

Endovascular thrombectomy (EVT) in addition to medical care results in significantly improved functional outcomes at 1 year in acute ischaemic stroke patients with a large core infarct compared with medical care alone, as shown in the SELECT2 study. This benefit persists across ischaemic core strata on imaging.

“In patients with ischaemic stroke due to a proximal occlusion and large core, thrombectomy plus medical care provided a significant functional outcome benefit compared with medical care alone at 1-year follow-up,” said lead author Amrou Sarraj, MD, from the Department of Neurology, University Hospital Cleveland Medical Center, Cleveland, Ohio, US. [Lancet 2024;403:731-740]

Sarraj presented these findings at the recent AAN 2024. He and his team assessed the efficacy and safety of EVT in the SELECT2 trial using clinical outcomes at 1-year follow-up.

SELECT2 was a phase III international, multicentre, prospective, randomized, open-label trial. Sarray and colleagues randomized 352 patients with a large ischaemic core to receive either EVT plus best medical management (n=178) or best medical management only (n=174). The median core volumes in the two groups were 74 and 77 ml, respectively.

A large ischaemic-core volume was defined as an Alberta Stroke Program Early Computed Tomography Score (ASPECTS) of 3 to 5 (range, 0 to 10, with lower scores indicating larger infarction) or a core volume of at least 50 ml on computed tomography perfusion or diffusion-weighted magnetic resonance imaging. [Lancet 2024;403:731-740]

The modified Rankin Scale (mRS) score at 1-year follow-up served as the primary outcome and was calculated using generalized odds ratio (OR). Other outcomes measured were as follows: functional independence (mRS 0‒2), independent ambulation (mRS (0‒3), and quality of life scores at 1 year.

Of the patients, 329 (93 percent) completed the 1-year follow-up for the primary outcome at 31 sites across the US, Canada, Spain, Australia, and New Zealand. [Sarraj, et al, AAN 2024]

EVT, compared with medical care alone, led to significant improvements in the 1-year mRS score distribution (Wilcoxon-Mann-Whitney probability of superiority, 0.59, 95 percent confidence interval [CI], 0.53‒0.64; p=0.0019; generalized OR, 1.43, 95 percent CI, 1.14‒1.78), functional independence (24 percent vs 6 percent; relative risk [RR], 3.17, 95 percent CI, 1.73‒5.79), and independent ambulation (37 percent vs 18 percent; RR, 1.85, 95 percent CI, 1.30‒2.63).

EVT also demonstrated more favourable effect estimates across ASPECTS (0‒2: generalized OR, 1.20, 95 percent CI, 0.58‒2.51; 3‒5: generalized OR, 1.48, 95 percent CI, 1.14‒1.88; 6‒10: generalized OR, 1.44, 95 percent CI, 0.80‒2.61) and ischaemic core strata (≥70 ml: generalized OR, 1.33, 95 percent CI, 1.04‒1.70; ≥100 ml: generalized OR, 1.08, 95 percent CI, 0.81‒1.44; ≥100 ml: generalized OR, 1.44, 95 percent CI, 0.90‒2.31).

Adverse effects

Mortality rates at 1-year follow-up were similar between patients who received EVT (77 of 170, 45 percent) and those who received medical care only (83 of 159, 52 percent; RR, 0.89, 95 percent CI, 0.71‒1.11). [Lancet 2024;403:731-740]

Notably, EVT was associated with a few procedural complications, with arterial access-site complications occurring in five patients, dissection in 10, cerebral-vessel perforation in seven, and transient vasospasm in 11. One patient in the EVT group and two in the medical care group also experienced symptomatic intracranial haemorrhage. [N Engl J Med 2023;388:1259-1271]