To evaluate the rate of subarachnoid hemorrhage(SAH) and its determinants during mechanical thrombectomy(MT).

Our study included a retrospective cohort of patients undergoing MT from 2/7/2015 to 6/29/2017 in a large tertiary care academic center. Data was collected by independent chart review of electronic medical records. A multivariate logistic regression analysis was performed using IBM SPSS 25.0 software. 

180 patients were included with mean age 72.8±13.8 years and 50% were women. Both anterior (ICA-M1 78.1%, M2-3 15.7%) and posterior circulation (basilar 4.5%, PCA 1.7%) strokes were included. Mean NIHSS on presentation was 16.4±6.2. 106(58.9%) received IV-TPA and 60(33.3%) received IA-TPA. Successful re-canalization(TICI 2b–3) was achieved in 84.2%(149/177) patients. 8.3%(11/180) patients developed SAH with or without associated intra-cerebral hemorrhage(ICH) post MT, confirmed on repeat imaging in 24-36hours. 20%(3/15, p=0.76) patients with SAH had post procedural neurological deterioration including death of one patient. 73.3%(11/15) with SAH received IA-tPA(OR 11.8, CI 2.5–55.8, p=0.002), which was adjusted for factors including, age(p=0.26), sex(p=0.04), co-morbidities, anti-coagulation at baseline(p=0.44), administration of IV-tPA(p 0.62), initial NIHSS(p=0.59), time from onset-of-symptoms to groin-puncture(p=0.96), intra-operative IA-Verapamil administration(p 0.80), number of passes(p 0.98) and TICI score(p=0.67). 86.7%(13/15) with SAH±ICH had MRS score of 4-6 on discharge(OR 4.12, p=0.04). 

IA-tPA administration during MT in patients with LVO is associated with increased odds of SAH±ICH with worse outcomes based on MRS score 4-6 at discharge. The benefit and safety of administration of IA-tPA with stent retriever thrombectomy is not fully defined and needs further study.