Abstract 3232: Distal Embolization Predicts Infarct Growth and Futile Recanalization after Endovascular Stroke Therapy
OBJECTIVE With the growing use of intra-arterial devices in acute stroke therapy, distal embolization (DE) is increasingly encountered. Reports described the incidence of these emboli but none so far linked them to the futile recanalization phenomenon. We report DE impact on clinical and radiographic outcomes in relation to futile recanalization.
METHODS This is a retrospective longitudinal cohort including all anterior circulation stroke patients treated using intra-arterial therapy in our center between 2005 and 2011. Patients enrolled in randomized trials were excluded. Baseline and follow-up CT scans were scored by a stroke neurologist and a neuro-radiologist blinded to the clinical and angiographic data. Angiograms were reviewed by an experienced interventional neuro-radiologist blinded to the clinical and radiographic outcome. DE is defined as any luminal filling defect in the arterial tree distal to the thrombus or any new luminal filling defect in a different arterial territory evaluated at final cerebral angiogram. Infarct growth was defined as a drop of two points in ASPECTS on noncontrast CT follow up scan compared to baseline.
RESULTS Eighty two patients (mean age 68 [13.8] years, median NIHSS 17[IQR 7], median ASPECTS 8) were studied. Intravenous tPA was used in 63%. The median onset-to-puncture time was 209 (119) minutes. The occlusion site was the L/T-type carotid occlusion in 22%, proximal MCA in 53.7%, and M2-MCA in 24.3%. The Merci device was used in 28%, Penumbra system in 31.7%, angioplasty balloon in 18.3%, and retrievable stents in 11%. Intra-arterial tPA was also used in 59% of cases. Successful recanalization (TICI 2b/3) was achieved in 43%. Distal emboli occurred in 45.1% of cases, 10% of which were in the ACA territory. Despite successful recanalization, infarct growth occurred in 28.6% of patients. DE occurred in 80% (8/10) of those with infarct growth and recanalized vs. 60% (15/25) in those who had no infarct growth and recanalized. Good clinical outcome (mRS 0-2) at discharge was noted in 58.3% of patients with successful recanalization and no DE, 30.4% in those with successful recanalization and DE, and 17% in those who did not recanalize (TICI 0-2a) (p=0.015).
CONCLUSIONS DE is common in the setting of endovascular stroke therapy and is associated with infarct growth and worse outcomes despite successful recanalization. DE may be one factor contributing to the futile recanalization phenomenon. This retrospective, single center experience needs to be validated in endovascular clinical trials.
- © 2012 by American Heart Association, Inc.