Abstract TP22: A Comparison of Clinical Outcomes Among Patients Receiving Mechanical Thrombectomies and tPA

Abstract

Introduction: The two treatment options for acute ischemic stroke (AIS) are tissue plasminogen activator (tPA), or mechanical thrombectomy (MT) for large-vessel occlusions. This study compares clinical outcomes among patients treated with tPA and MT, and the relationship between outcomes and the time to treatment. Hypothesis: Patients receiving MT and tPA have superior outcomes to those receiving no thrombolytic therapy, and the effects are greatest when treatment is administered shortly after admission. Methods: De-identified clinical data was obtained from 2191 stroke patients admitted to St. David’s Medical Center (Austin, TX), of whom 239 received tPA and 137 received MTs (45 received both). Acute ischemic stroke (AIS) patients were stratified into 4 groups defined by their admission NIH Stroke Scale (mild 0-5, moderate 6-15, moderate-severe 16-21, severe 21-42). Discharge modified Rankin Scores (mRS) were used to compare outcomes in 4 treatment groups: MT, tPA, both, neither, with significance assessed using t-tests. The relationships between outcomes and door to needle/groin time (DNT, DGT) were determined using linear regression. Results: Shorter DGT and DNT times are associated with lower mRS at discharge (DGT: partial correlation ρ c =0.040, p > 0.05; DNT: ρ c =0.258, p << 0.001). Among moderate and moderate-severe strokes, treatment with both MT and tPA was associated with significantly lower mRS scores than those treated with neither (p << 0.001), only MT (p = 0.005), or only TPA (p = 0.03). In moderate-severe strokes, MT alone was associated with significantly lower discharge mRS scores relative to untreated strokes (p = 0.03), whereas tPA was not. In mild and severe strokes, the differences in outcomes among the 4 treatment groups were small and not significant. Conclusions: This study suggests that strokes treated with both tPA and MT have better outcomes than strokes only one treatment, and that strokes treated with either tPA or MTs have better outcomes than untreated strokes. Shorter DNT times significantly improve outcomes for patients receiving tPA, whereas shorter DGT times are less strongly associated with improved outcomes. Our results highlight the importance of timely administration of stroke treatments to outcome improvement.