Abstract 74: Early Arterial Recanalization After Intra-venous Tissue-Plasminogen-Activator Treatment in the Interventional Management of Stroke-3 Study

Abstract

Background: Data on arterial recanalization after IV t-PA treatment are rare. IMS-3 allows the study of variables affecting arterial recanalization after IV t-PA in acute ischemic stroke patients with CTA-proved major artery occlusions. Methods: Of 656 acute ischemic stroke patients in IMS-3, 306 were examined with baseline CTA and randomized either to IV t-PA (N=95) or to IV t-PA followed by digital subtraction angiography (DSA) and endovascular therapy (EVT) (N=211). Comparison of baseline CTA to DSA within 5 hours of stroke onset assessed early arterial recanalization after IV t-PA. A central core lab categorized DSA vessel occlusion as “no, partial, or complete”. We studied the association between arterial occlusion sites on baseline CTA with early recanalization for the endovascular group and analyzed its impact on clinical outcome at 90 days. Results: In the EVT group, 22 patients (10.4%) had no CTA intracranial occlusions, but 1 extracranial occlusion; 42 patients (19.9%) had occlusions of intracranial internal carotid artery (ic-ICA); 10 patients (4.7%) had tandem occlusions of the cervical ICA and middle cerebral artery (MCA); 95 patients (45.0%) had MCA-trunk (M1) occlusions, 33 patients (15.6%) had M2 occlusions, 3 patients (1.4%) had M3/4 occlusions, and 6 patients (2.8%) occlusions within posterior circulation. Partial or complete recanalization occurred in 28.6% of patients before DSA and was marginally associated with occlusion site (p=0.0525) (8 patients (19.0%) with ic-ICA occlusion, 0 patients with tandem ICA/MCA occlusions, 34 patients (35.8%) with M1 occlusions, 11 patients (33.3%) with M2 occlusions, 0 patients with M3/4 occlusions, and 1 patient (16.7%) with occlusion within posterior circulation). Three CTA negative patients had intracranial occlusions on DSA. Thirty-two patients (59.3%) with early recanalization achieved mRS of 0-2 at 90 days compared to 51 patients (38.4%) without early recanalization (p=0.0099). There was no relationship between early recanalization and time to IV t-PA or mean t-PA dose. Conclusion: Before EVT, IV rt-PA may facilitate arterial recanalization and better clinical outcome in about one third of patients.