Abstract WMP8: Clinical Outcomes After Mechanical Thrombectomy in Acute Ischemic Stroke Patients Aged 65 Years and over: a Subgroup Analysis of the Stratis Registry

Background: Mechanical thrombectomy (MT) with stent retrievers for treatment of acute ischemic stroke due to large vessel occlusion has become standard of care. In this study, we aimed to evaluate clinical outcomes in patients aged 65 and over based on data collected in a large real world registry and compared the outcomes to those reported in the randomized trials. Methods: STRATIS was a prospective, multicenter, observational, single-arm registry designed to capture a “real world experience” without requiring specialized imaging, age limits or technique exclusions at academic and non-academic centers in the USA. Patients with large vessel occlusion acute ischemic stroke were enrolled within 8 hours from symptom onset. In this post hoc analysis, a subgroup of patients aged ≥65 years were evaluated and then compared in a patient level analysis with the interventional arm of the pooled randomized SEER cohort. Results: Of the total 984 patients enrolled in STRATIS, 603 patients aged ≥65 years were included in the analysis. Mean age was 77.2; 47.8% were male. Median baseline NIHSS was 18 and 61.5% received IV tPA. Median times from stroke onset to puncture, and puncture to TICI 2b/3 or completion, were 207 and 38 minutes, respectively. Final mTICI ≥2b (per core lab) was achieved in 88.2%. sICH was seen in 1.4%. At 90 days, 51.8% achieved mRS 0-2 and all-cause mortality was 18.6%. Results comparing STRATIS and SEER intervention cohorts of patients aged ≥65 years are presented in the table. mTICI ≥2b rate was significantly higher in STRATIS. In unadjusted analysis, similar rates of mRS 0-2, mortality and sICH were observed. In an adjusted analysis, the odds for achieving mRS 0-2 were significantly higher in STRATIS compared to SEER intervention cohort (OR 1.43; 95%CI 1.03-1.99; p=0.03). Conclusion: STRATIS documents that MT can be safely performed in patients aged 65 and over in a real world setting with comparable technical and clinical outcomes to those observed in the randomized trials.