Thrombolysis in Cerebral Infarction (TICI) 2b Versus TICI 3 Reperfusion in Stroke Patients with Mild Symptoms

The treatment effect of mechanical thrombectomy in patients with mild stroke symptoms and large vessel occlusion remains unclear. Furthermore, it is uncertain whether achieving complete reperfusion (modified Thrombolysis in Cerebral Infarction [mTICI] 3) offers additional clinical benefit compared to incomplete reperfusion (mTICI 2b) in patients with mild stroke.

In this retrospective, multicenter analysis, all patients enrolled in the German Stroke Registry-Endovascular Treatment between 2015 and 2023 (n = 18,069) were evaluated. The study included patients with a National Institutes of Health Stroke Scale (NIHSS) score of < 6 and anterior circulation large vessel occlusion. Clinical outcomes were compared between mTICI 2b and mTICI 3. The primary endpoint was excellent functional outcome at 90 days, defined as a modified Rankin Scale (mRS) score of 0-1.

Of the 747 included patients, 37% achieved mTICI 2b and 63% mTICI 3. An excellent functional outcome was observed at similar rates in both groups (mTICI 2b: 59% vs. mTICI 3: 60%; P = 0.83; adjusted OR: 0.96 [95% CI: 0.66-1.40]; P = 0.84). The rates of symptomatic intracranial hemorrhage (4% vs. 3%; P = 0.36) and 90-day mortality (10% vs. 7%; P = 0.26; adjusted OR: 0.80 [95% CI: 0.42-1.50]; P = 0.49) were also comparable between the two groups.

Among thrombectomy patients with mild stroke, complete reperfusion was not associated with better functional outcomes than incomplete reperfusion. These findings suggest that mTICI 2b may be an acceptable final angiographic result and raise questions about the risk-benefit ratio of additional retrieval maneuvers aimed at achieving mTICI 3.