Safety and effectiveness of endovascular treatment of stroke with unknown time of onset.

ABSTRACT

BACKGROUND: Currently, treatment options for patients with strokes with unknown time of onset (UKO) remain limited. With the advance of neuroimaging and endovascular treatment (EVT), selected patients might have a chance of a therapeutic option. We sought to compare clinical outcome after EVT in patients with known time of stroke onset (KO) and in those with UKO. METHODS: We prospectively registered consecutive patients with acute large artery occlusion of the anterior territory who underwent EVT. Multimodal MR or Alberta Stroke Program early CT score (ASPECTS) and transcranial color-coded Duplex sonography were used to select patients for EVT. Recanalization, periprocedural complications, intracranial hemorrhage (ICH) and outcome were recorded. Symptomatic ICH (sICH) was defined as a worsening of ≥4 points in the National Institutes of Health Stroke Scale (NIHSS) score within 36 h in any bleeding. Favorable outcome was defined as a modified Rankin score ≤2 at 3 months. RESULTS: A total of 141 patients were studied, 109 with KO and 32 with UKO. Mean age was 66.5 versus 64.7 years (p = 0.005) and median baseline NIHSS was 18 versus 17 (p = 0.095), respectively. Prior IV tPA was more frequently administered to KO patients (62.4 vs. 9.4%, p < 0.001), whereas patient selection using multimodal MR was more frequent in patients with UKO (78.1 vs. 45.4%, p < 0.001). Median time from stroke onset or from the last time the patient was seen well to groin puncture and to recanalization was significantly longer in patients with UKO, but no differences were found in the duration of the procedure. For KO/UKO patients recanalization was seen in 77.1 vs. 65.7% (p = 0.084), sICH occurred in 10 versus 0% (p = 0.061) and favorable outcome at 3 months was achieved in 41.3 versus 50% (p = 0.382), respectively. CONCLUSIONS: Clinical outcomes in this series of EVT in ischemic stroke patients due to large anterior arterial occlusion with salvageable brain are similar for patients treated with KO and UKO. These data support a randomized study of EVT in extended or uncertain time windows..