Anterior Cerebral Artery Emboli in Combined Intravenous and Intra-arterial rtPA Treatment of Acute Ischemic Stroke in the IMS I and II Trials

S King,J Carrozella,T Tomsick,J Spilker,P Khatri,J Broderick,M Hill

doi:10.3174/ajnr.a0702

Abstract

Anterior cerebral artery (ACA) emboli may occur before or during fibrinolytic revascularization of middle cerebral artery (MCA) and internal carotid artery (ICA) T occlusions. We sought to determine the incidence and effect of baseline and new embolic ACA occlusions in the Interventional Management of Stroke (IMS) studies. Case report forms, pretreatment and posttreatment arteriograms, and CTs from 142 subjects entered into IMS I & II were reviewed to identify subjects with baseline ACA occlusion, new ACA emboli occurring during fibrinolysis, subsequent CT-demonstrated infarction in the ACA distribution, and to evaluate global and lower extremity motor clinical outcome. During M1/M2 thrombolysis procedures, new ACA embolus occurred in 1 of 60 (1.7%) subjects. Baseline distal emboli were identified in 3 of 20 (15%) T occlusions before intra-arterial (IA) treatment, and new posttreatment distal ACA emboli were identified in 3 subjects. At 24 hours, 8 (32%) T occlusions demonstrated CT-ACA infarct, typically of small volume. Infarcts were less common following sonography microcatheter-assisted thrombolysis compared with standard microcatheter thrombolysis (P = .05). Lower extremity weakness was present in 9 of 10 subjects with ACA embolus/infarct at 24 hours. The modified Rankin 0 to 2 outcomes were achieved in 4 of 25 (16%) subjects with T occlusion overall, but in 0 of 10 subjects with distal ACA emboli or ACA CT infarcts (P = .07). With IV/IA recombinant tissue plasminogen activator treatment for MCA emboli, new ACA emboli are uncommon events. Distal ACA emboli during T-occlusion thrombolysis are not uncommon, typically lead to small ACA-distribution infarcts, and may limit neurologic recovery.

Highlights

AND PURPOSE: Anterior cerebral artery (ACA) emboli may occur before or during fibrinolytic revascularization of middle cerebral artery (MCA) and internal carotid artery (ICA) T occlusions
Distal arterial emboli may be sequelae of intravenous (IV) and intra-arterial (IA) fibrinolysis of the middle cerebral artery (MCA) and distal internal carotid artery (ICA) “T” occlusions as the initial thrombus fragments.[1]
The clinical significance of secondary distal emboli liberated during therapeutic recanalization of MCA and ICA T occlusions has not been analyzed

Summary

Methods

Case report forms, pretreatment and posttreatment arteriograms, and CTs from 142 subjects entered into IMS I & II were reviewed to identify subjects with baseline ACA occlusion, new ACA emboli occurring during fibrinolysis, subsequent CT-demonstrated infarction in the ACA distribution, and to evaluate global and lower extremity motor clinical outcome. Subjects with acute ischemic stroke defined by a baseline National Institutes of Health Stroke Scale (NIHSS) score Ն10 were enrolled within 3 hours of the onset of symptoms and treated with IV tPA at a reduced dose (0.6 mg/kg over 30 minutes with 15% of the dose given as an initial bolus). They were taken immediately to the neuroangiography suite for endovascular therapy. In IMS II, the sonography microcatheter was to be placed into the proximal aspect of the thrombus, with no manipulation of the guidewire, but incrementally advanced as thrombolysis was demonstrated on subsequent control arteriograms

Results

Discussion

Conclusion