Intravenous Thrombolysis in Distal Medium Middle Cerebral Artery Occlusion Patients with Unsuccessful Mechanical...

The efficacy and safety of intravenous thrombolysis (IVT) in acute ischemic stroke (AIS) patients undergoing mechanical thrombectomy (MT) for distal, medium vessel occlusions (DMVO) is not well established. This study investigates whether IVT impacts outcomes in DMVO patients, particularly in those with unsuccessful or partial recanalization after MT.

We conducted a retrospective, multicenter study using data from the Multicenter Analysis of primary Distal medium vessel occlusions: effect of Mechanical Thrombectomy (MAD-MT) registry. The study population included AIS patients with DMVO in the M2, M3, and M4 segments of the MCA, treated with or without IVT followed by MT and a final modified Thrombolysis in Cerebral Infarction (mTICI) score of 0, 1, or 2a. The primary outcome was functional independence, assessed by the 90-day modified Rankin Scale (mRS) of 0-1 or 0-2.

The study comprised 210 patients with final mTICI 0 to 2a, with 130 undergoing MT alone and 80 receiving IVT followed by MT. Logistic regression analysis revealed no significant differences in clinical outcomes between groups. The odds ratios (ORs) for achieving a 90-day mRS of 0-1 and 0-2 were 1.55 (95% CI 0.62 to 3.87; p = 0.34) and 1.55 (95% CI 0.72 to 3.37; p = 0.26), respectively. The odds of symptomatic intracerebral hemorrhage (sICH) were similar between groups (OR 0.64, 95% CI 0.28 to 1.47; p = 0.29), as were the odds of intracranial hemorrhage (ICH) of any type (OR 1.39, 95% CI 0.71 to 2.73; p = 0.34).

In AIS patients with DMVO and unsuccessful or partial recanalization after MT, IVT did not significantly improve clinical outcomes. Additionally, IVT did not increase the risk of hemorrhagic complications. These findings suggest that while IVT preceding MT is safe in this context, it may not improve outcomes for patients with unsuccessful MT.