Predictors of tissue-type plasminogen activator nonresponders according to location of vessel occlusion

Background and Purpose-: Information on the clinical and hemodynamic profile of intravenous tissue-type plasminogen activator nonresponders, at different locations of arterial occlusion, may improve the selection of candidates for rescue reperfusion therapies. Therefore, we aim to investigate predictors of failing intravenous tissue-type plasminogen activator therapy according to occluded vessel and location of the clot. Methods-: We prospectively evaluated consecutive patients with an acute ischemic stroke admitted within the first 6 hours of onset. Five hundred forty-eight patients with documented intracranial occlusion were included. Patients were categorized according to site of vessel occlusion into 4 distinct groups: proximal middle cerebral artery occlusion (n=251), distal middle cerebral artery occlusion (n=194), internal carotid artery bifurcation occlusion (n=61), and basilar artery occlusion (n=42). Recanalization was assessed on transcranial Doppler at 1 hour of tissue-type plasminogen activator bolus. Results-: Among patients with proximal middle cerebral artery occlusion, the presence of severe extracranial internal carotid artery stenosis or occlusion (OR, 2.36; 95% CI, 1.15-4.84; P=0.02) and age >74 years (OR, 1.84; 95% CI, 1.02-3.31; P=0.04) independently predicted no recanalization. No independent predictors of no recanalization were identified in patients with distal middle cerebral artery occlusion. In patients with internal carotid artery bifurcation occlusion, a previous diagnosis of hypertension (OR, 12.77; 95% CI, 2.12-76.88; P=0.05), and absence of atrial fibrillation (OR, 8.15; 95% CI, 1.40-47.44; P=0.02) emerged as independent predictors of no recanalization. Similarly, among patients with basilar artery occlusion, absence of atrial fibrillation was as an independent predictor of no recanalization (OR, 7.50; 95% CI, 1.40-40.35; P=0.02). Conclusions-: The use of relevant predictors of no recanalization and a rapid neurovascular evaluation may improve the selection of patients for more aggressive rescue strategies.