P-015 flow stasis after the deployment of stent-retriever predicts successful final recanalization in acute stroke patients

Background The aim of this study was to evaluate the clinical significance of immediate flow restoration (IFR) after deployment of a stent retriever in acute stroke patients. Method A total of 205 patients underwent revascularization for acute cerebral vessel occlusion in this period. Fifty-six patients who were evaluated IFR after stent retriever deployment on digital subtraction angiography were enrolled in this study. Mean age was 77.0 years (27–94), and females were 33 (58.9%). Atrial fibrillation was found in 42.9%, and anti-coagulated agents were administrated in 21.4%. Ten patients had past history of stroke (17.9%). Mean NIHSS on admission was 17(1–38). Result Successful final recanalization (TICI 2B and 3) was achieved in 67.9% in this cohort. IFR occurred in 42 patients (75.0%), but IFR itself was not associated with successful recanalization (p=NS). In 21 patients (37.5%), additional intermittent angiography was performed prior to retrieving the stent retriever. The intermittent angiography showed loss of the IFR (complete flow stasis or diminished distal flow) in 12 patients (57.1%) and unchanged in 9 patients (42.9%). The loss of the IFR was associated a higher successful recanalization (91.6%) than those unchanged with lower recanalization (44.4%). The use of balloon guiding catheter (p = 0.011), NIHSS on admission (p = 0.018), and the loss of the IFR (p = 0.046) reached statistical significance on successful recanalization. The rate of favorable outcome and mortality at 90 days were 37.5% and 10.7% respectively. Successful recanalization (p = 0.039) was the independent predictors of favorable outcome. Those who found the loss of IFR had the higher rate of favorable outcome (41.7%) than those unchanged (22.2%), though it was not significant (p = 0.64). Conclusion Loss of IFR effect during the embedding time after deployment of stent retriever was associated with successful recanalization. It may be an angiographic sign of adequate thrombus engagement with the stent retriever. This observation may be useful in order to optimize the embedding time during which a stent retriever cuts into the occlusive thrombus particularly when a new stent retriever is introduced to the clinical practice. Disclosures S. Tateshima: 2; C; Covidien. M. Okawa: None. D. Liebeskind: None. R. Jahan: 2; C; Covidien. N. Gonzalez: None. V. Szeder: None. N. Rao: None. L. Ali: None. D. Kim: None. J. Saver: None. G. Duckwiler: 2; C; Covidien.