Failure to Utilize Intravenous tPA Before Thrombectomy May Worsen Outcomes

A study presented at the International Stroke Conference in Los Angeles Feb 19-21, 2020 by Saurabh Sudesh et al examined prethrombectomy factors and outcome measures after acute ischemic stroke (AIS). Mechanical thrombectomy has proven efficacy for revascularization after AIS and positive clinical outcomes after AIS. There are factors in addition to thrombectomy that may also have efficacy for positive outcomes, including time to recanalization and prethrombectomy use of intravenous (IV) tissue plasminogen activators (tPAs). The study retrospectively identified cases of successful thrombectomy to elucidate interactions between these factors and discharge neurological and functional status.

Individuals who had successful thrombectomy for acute ischemic stroke (TICI≥2b) with longer times to recanalization or who did not receive IV tPA before thrombectomy had poorer neurologic and functional outcomes at discharge. Data from individuals who underwent successful mechanical thrombectomy (TICI≥2b) between 2015 and 2018 for supratentorial proximal large-vessel occlusion (LVO) were included for analysis. Outcome measures included modified Rankin Scale (mRS) scores that were worse at discharge vs admission, and National Institutes of Health Stroke Scale (NIHSS) scores that improved by less than 8 points, respectively reflecting poor functional and neurologic outcomes. Univariate and multivariate statistical analysis of the data was performed. 

Worsened functional status at discharge correlated with longer times to recanalization (P=0.015). Those who did not have IV tPA before thrombectomy were also more likely to have worsened functional outcomes (P=0.027) Prethrombectomy IV tPA use also correlated negatively with worsened neurologic outcomes at discharge (P=0.001). These correlations were statistically significant (P<0.05) on multivariate analyses.

Time to recanalization ranged from 1.58 to 16.37 hours. Of 101 individuals, 57 (56.4%) had IV tPA prior to thrombectomy. 

Future prospective, controlled studies are warranted to confirm and further characterize these findings, which will allow for more nuanced risk-stratification and indications for this relatively new treatment modality.