In the RESCUE BT (endovascular treatment with versus without tirofiban for stroke patients with large vessel occlusion) trial, enrollment in extended time window was based on noncontrast computed tomography. To assess whether perioperative intravenous tirofiban would further enhance the clinical benefit of endovascular therapy in the RESCUE BT trial according to advanced imaging criteria based on current American Heart Association/American Stroke Association (AHA/ASA) guidelines. This is a secondary analysis of the RESCUE BT trial. Patients who were eligible for endovascular thrombectomy in the 6h window and met the criteria of the DAWN or DEFUSE 3 trials in the extended window according to the AHA/ASA guidelines were analyzed. The primary outcome was the distribution of the 90-day modified Rankin Scale (mRS) scores. Safety outcomes included the incidence of symptomatic intracranial hemorrhage (sICH) within 48h and 90-day mortality. A total of 652 patients (319 in tirofiban group and 333 in placebo group) who meeting the AHA/ASA guidelines were included in this analysis, with median interquartile ranges (IQR) age of 68 (58-75) years, 278 (42.6%) were women. The median 90-day mRS score was 3 (IQR, 1-4) in the tirofiban group, and 3 (IQR, 1-4) in the placebo group. The adjusted common odds ratio (OR) for a lower level of disability with tirofiban than with placebo was 1.08 (95% CI: 0.83-1.42). The incidence of sICH [10.1% versus 6.3%; adjusted OR 1.70; (95% CI: 0.95-3.04)] was not significantly different between groups. However, intravenous tirofiban might be associated with lower disability level [adjusted common OR, 1.74 (95% CI: 1.14-2.65); P =0.01] in patients with large artery atherosclerosis. There was no significant difference in the severity of disability at 90 days with intravenous tirofiban compared to placebo in patients who underwent endovascular therapy according to AHA/ASA guidelines. The authors observed potential benefits of tirofiban in patients with large artery atherosclerosis, but there was an increased risk of sICH in patients with cardioembolism stroke.