Abstract Body: Introduction: Randomized clinical trials have demonstrated efficacy and safety of endovascular thrombectomy (EVT) among patients presenting up to 24 hours of last known well (LKW). Recent reports have suggested EVT could result in better functional outcomes with acceptable risk profile even in patients presenting beyond 24 hours of LKW, but exploration of the role of EVT in elderly patients presenting beyond 24 hours is limited.
Methods: We aimed to evaluate functional and safety outcomes for EVT in patients with age ≥80y with a large vessel occlusion (LVO) beyond 24 hours of LKW, from a pooled, international cohort (17 centers across US, Spain, Australia and New Zealand) between 7/2012 and 12/2021. Primary outcome was a shift on modified Rankin Scale score at 90-day follow-up.
Results: Of 301 included, 88 (53 EVT, 35 medical management MM) were aged ≥80y, with 57 females and 21 nonagenarians. Median(IQR) NIHSS - 17.5 (11-22),CT ASPECTS - 7(4-9), ischemic core 5.5 (0-26) ml. Overall, as age increased, clinical outcomes worsened (acOR: 0.64, 95% CI: 0.55-0.74, p<0.001 per 10 year increment). However, EVT was associated with a shift towards better functional outcome among patients with age≥80y (acOR: 8.31, 95% CI:2.80-24.68, p<0.001) and among patients with age<80y (acOR: 2.11, 95% CI: 1.22-3.66, p=0.008), with a significant interaction (p-int:0.047 – fig1) suggesting higher improvement within octogenarians. Estimates of Functional independence (EVT: 27% vs MM: 6%, aOR: 11.86, 95% CI: 1.75-80.28, p=0.011) and mortality (EVT: 42% vs MM: 71%, aOR: 0.16, 95% CI: 0.05-0.52, p=0.003) also favored EVT, with similar results obtained using inverse probability of treatment weights [Table 1]. 4 patients within EVT arm and no patients within MM arm developed symptomatic ICH. Among octogenarians receiving EVT, lower presentation NIHSS (aOR: 0.77, 95% CI: 0.64-0.92, p=0.003 per point increment) and presence of M2 occlusion (aOR: 11.01, 95% CI: 1.15-105.36, p=0.037 were independently associated with functional independence at 90-day follow-up), but not time to procedure (aOR: 0.99, 95% CI: 0.96-1.02, p=0.64, fig2).
Conclusions: In a pooled international cohort of octogenarians who presented beyond 24 hours with an LVO, EVT was associated with better functional outcomes, higher functional independence and lower mortality. Lower stroke severity and presence of M2 occlusion were independently associated with functional independence at 90-day after EVT.