Abstract TP71: Predicting Benefit Of Thrombectomy In Patients With NIHSS <6 And Potential Role Of Thrive Score In Patient Selection For Reperfusion Therapy

Introduction: Evidence is unclear for invention in patients with a mild stroke (low NIHSS) and LVO (large vessel occlusion) as only 15-17 patients with NIHSS < 6 were included in the randomized trials. Cohort studies report good and poor outcomes in low NIHSS LVO cases, with some reporting poor complications secondary to complications and associated with burden of chronic illness. The THRIVE (Total Health Risk in Vascular Events) score was previously associated with poor outcomes in stroke patients. We hypothesized that the THRIVE score may be associated with poor outcomes in low NIHSS LVO patients. Methods: An IRB approved retrospective stroke study from January 2015 to December 2019 was used. Out of 2401 eligible acute ischemic stroke patients, 107 patients with an NIHSS < 6 with an LVO were included in the analysis. Non-parametric t-test, Chi-squared, and logistic regression were used for statistical analysis. Results: Of the 107 patients, the median age was 65 (55-74, interquartile range (IQR), 36% were female, 79% Caucasian, 44% had a discharge modified Rankin Score (mRS) of 0-1, 65% had a THRIVE score < 3, and time from LSN to presentation was 210 minutes (89 – 723 IQR). There was no difference in age, gender, race, time from LSN, or percent of patients with a THRIVE score < 3 (55% with IR vs 65% No IR). However, patients treated with a thrombectomy were significantly less likely to have a good neurologic outcome with discharge mRS of 0-1 if taken for thrombectomy (0% IR group versus 49% No IR, p=<0.0001). Of those taken for IR, 4 were basilar artery occlusions with poor outcomes, 4 MCA occlusions re-occluded post-IR were complicated by re-occlusion or high-grade stenosis. Notably, 54% had TTP lesions with cortex, but only 2 patients had significant cortical infarcts, and there was no symptomatic hemorrhagic conversion. Conclusion: Decision-making on IR for patients with low NHISS should be tailored to the patient, as it is likely that the inherent clinical factors prompting thrombectomy to be considered despite the low NIHSS are the important driving factors increasing the likelihood of worse outcomes. Further research is needed to evaluate the type of neurologic deficits and the eloquence of the tissue involved.