Background and Purpose Mechanical thrombectomy has significantly improved post-ischemic stroke clinical outcomes. However, the post-ischemic stroke mortality rate appears to be unchanged. We reviewed potential risk factors that can be related to mortality in patients who underwent mechanical thrombectomy.

Materials and Methods A retrospective review was conducted in acute anterior circulation ischemic stroke patients who underwent mechanical thrombectomy but expired within 90 days in a high volume comprehensive stroke center between January 2017 and January 2020. Pre thrombectomy risk factors evaluated include age, NIHSS, ASPECT score, baseline mRS, occlusion site, and IV tPA administration. Post-thrombectomy risk factors include ASPECT score at 24 hours, TICI score, post-procedural subarachnoid hemorrhage (SAH), hemorrhagic transformation, and decompressive craniectomy. Procedural risk factors included the mode of anesthesia, intraprocedural systolic (SBP), diastolic (DBP), and mean arterial pressure (MAP) were reviewed as well as procedural blood pressure variability. The difference between the highest and lowest recorded blood pressure was defined as procedural variability.

Results Mechanical thrombectomy was performed in 290 patients, and 54 patients (54/290, 18.6%) were expired at 90 days, which include 42 anterior (77.8%) and 22 posterior circulation patients (22.2%). In 42 anterior circulation acute ischemic stroke patients who expired (M:F=25:17), the mean age was 77.5 ± 13, and 42.86% was at or more than 80 years old. Baseline estimated mRS three or above were seen in 92.7%. The number of days from admission to decease was 7 (median). Pre-procedural ASPECT score >6 was noted in 32 patients (32/42, 76.19%) but in 11 patients (11/42, 26.19%) on post-procedure ASPECT at 24 hours. MCA, ICA and CCA occlusion was found in 69.05%, 19.5%, and 9.52%, respectively. Pre thrombectomy IV tPA was administered in 17 patients (17/42, 40.48%). TICI 2b or three were achieved in 54.7%, with the median number of passes were 2. Ten patients (23.81%) developed post thrombectomy symptomatic intracranial hemorrhages (sICH), and the hemorrhagic transformation was seen in 14.29% (n=6). Three patients (7.14%) received decompressive craniectomy. Mean ‘arrival to groin puncture time’ and ‘groin to reperfusion time’ were 1.13 ± 0.19 hours and 1 hour ± 0.042, respectively. Monitored Anesthesia Care (n=29, 69.04%) was used for most of the procedure. Mean procedural variability of MAP, DBP and SBP were 24.32 + 23.79 mmHg, 16.38 ± 24.83 mmHg, and 40.19 ± 26.83 mmHg, respectively.

Conclusion Older age, low baseline estimated mRS, the relatively lower rate of successful reperfusion, the higher rate of sICH, delayed groin to reperfusion time, and higher intraprocedural variability in MAP and DBP were observed in patients with mortality in our study.

Disclosures A. Toma: None. A. Vijayashankar: None. N. Haranhalli: None. R. Zampolin: None. D. Altschul: None. A. Brook: None. S. Lee: None.