Rates and Impact of Serious Adverse Events after Endovascular Thrombectomy among Large Vessel Occlusion Stroke Patients

Objective: Complications or serious adverse events (SAEs) are common in the treatment of patients with large vessel occlusion stroke. There has been limited study of the impact of SAEs for patients after endovascular thrombectomy (EVT). The goal of this study was to characterize the rates and clinical impact of SAEs following EVT. Methods: A post hoc analysis was performed using pooled databases of the "DEVT" and "RESCUE BT" trials. SAEs were designated as symptomatic intracranial hemorrhage, brain herniation or craniectomy, respiratory failure, circulatory failure, pneumonia, deep venous thrombosis, and systemic bleeding. The primary endpoint was functional independence (modified Rankin scale score 0-2 within 90 days). Logistic regression analysis was used to determine the predictors and associations between SAEs and outcomes. Results: Of 1,182 enrolled patients, 402 (34%) had a procedural complication and 745 (63%) had 1,404 SAE occurrences with 4.65% in-hospital mortality. The three most frequent SAEs were pneumonia (620, 52.5%), systemic bleeding (174, 14.7%), and respiratory failure (173, 14.6%). Pneumonia, systemic bleeding, or deep venous thrombosis was less life-threatening. Patients with advanced age (adjusted odds ratio, 1.28 [95% confidence interval, 1.14-1.43]), higher NIHSS (1.09 [1.06-1.11]), occlusion site (middle cerebral artery-M1 vs. internal carotid artery [ICA]: 0.75 [0.53-1.04]; M2 vs. ICA: 1.30 [0.80-2.12]), longer procedure time (1.01 [1.00-1.01]), and unsuccessful vessel recanalization (1.79 [1.06-2.94]) were more likely to experience SAEs. Compared with no SAE, patients with SAEs had lower odds of functional independence (0.46 [0.40-0.54]). Conclusions: Overall, SAEs diagnosed following thrombectomy in patients with stroke were common (more than 60%) and associated with functional dependence. Patients with advanced age, higher NIHSS, longer procedure time, and failed recanalization were more likely to experience SAEs. There was no statistical difference in the risk of SAEs among patients with M1 and M2 occluded compared with those ICA occluded. An understanding of the prevalence and predictors of SAEs could alert clinicians to the estimated risk of an SAE for a patient after EVT.