Introduction: Mechanical thrombectomy (MT) improves clinical outcome of patients with acute ischemic stroke (AIS) and a large vessel occlusion. Approximately 90% of patients in the recent MT trials received intravenous thrombolysis (IVT) prior to MT.
Aim: To determine if IVT in combination with MT is superior to MT alone in patients with AIS and a large vessel occlusion.
Methods: A patient-level pooled analysis of the STAR and SWIFT studies, two large multicenter prospective studies on MT for AIS was utilized. Using multivariate logistic regression analysis, we compared mRS at follow-up, reperfusion rates, and complication rates (intracerebral hemorrhage and emboli to uninvolved territories) between patients who underwent MT following IVT, to those who underwent only MT. An independent core laboratory scored all radiological outcomes.
Results: Of 291 included patients, 160 (55%) underwent MT following IVT, and 131 (45%) underwent only MT. Of the patients treated with IVT, 116 were IVT failures (full tpa dose) and 44 received bridging therapy (mean tpa dose 0.62 mg/kg). Patients who received IVT less often had atrial fibrillation (33 vs. 47 %, p=0.016) and diabetes (14 vs. 24%, p=0.023), and had a lower mean ASPECTS (8.1 vs. 8.5, p=0.031) compared to thos who underwent only MT. There was no difference in baseline NIHSS (both median 17) or location of the occlusion between groups. We did not find a statistically significant association between use of IVT in addition to MT vs. MT alone for any of the outcomes. There were trends towards a lower risk of symptomatic intracerebral hemorrhage (adjusted OR 0.12, 95% CI 0.01-1.13), a higher risk of vasospasm (adjusted OR 1.81, 95% CI 0.86-3.80), and a higher chance of mRS 0-2 (adjusted OR 1.60, 95% CI 0.86-3.80) in patients who received MT following IVT, compared to MT alone.
Conclusions: We observed no statistically significant benefit or harm for the use of IVT in addition to MT in patients with AIS and a large vessel occlusion.