Effect of bleeding risk prediction on decision making of intravenous thrombolysis before thrombectomy: a subgroup analysis of DIRECT-MT

BACKGROUND: The major concern for bridging intravenous thrombolysis (IVT) before endovascular thrombectomy (EVT) is the potentially increased risk of symptomatic intracerebral hemorrhage (sICH). Thus we conducted this study to clarify whether evaluation of individual bleeding risk could assist in the decision to perform IVT before EVT. METHODS: The study was a subgroup analysis of a randomized trial evaluating the safety and efficacy of IVT before EVT. The SEDAN (blood Sugar, Early infarct signs and (hyper) Dense cerebral artery sign, Age, and National Institutes of Health Stroke Score) score, GRASPS (Glucose, Race, Age, Sex, systolic blood Pressure, and Severity of stroke) score, and SITS-SICH (Safe Implementation of Thrombolysis in Stroke-Symptomatic Intracerebral Hemorrhage) score were used to evaluate individual bleeding risk. The primary outcome was functional independence, defined as a modified Rankin Scale (mRS) score of 0–2 at 90 days. Binary logistic regression with an interaction term was used to estimate treatment effect modification to clarify whether direct EVT was more beneficial in patients with a higher sICH risk, while adjunctive IVT before EVT was more beneficial in patients with a lower sICH risk. RESULTS: Among 658 randomized patients, 639 (361 men, 56.5%; median age 69 (IQR 61–76) years) were included in the study. With the SITS-SICH score as an example, adjusted OR for functional independence with EVT alone was 1.12 (95% CI 0.68 to 1.82) in patients with a lower sICH risk (SITS-SICH score 0–4) and 0.92 (0.53 to 1.60) in those with a higher sICH risk (SITS-SICH score 5–15). There were no treatment-by-bleeding-risk interactions for all dichotomized mRS outcomes based on the three scores (all p>0.05). CONCLUSIONS: We found no evidence that clinicians can decide whether to omit IVT before EVT based on an individualized assessment of bleeding risk.