Clinically asymptomatic hemorrhagic conversion is associated with need for inpatient rehabilitation following mechanical thrombectomy for anterior circulation ischemic stroke

Background Hemorrhagic conversion (HC) is a known complication following acute ischemic stroke(AIS) in patients undergoing mechanical thrombectomy(MT). While symptomatic HC(sHC) has been shown to lead to poor neurologic outcomes, the effect of asymptomatic HC(aHC) is unclear. This study aims to identify predictors of aHC and to determine the short-term outcomes. Methods This is a single-institution retrospective study of patients with anterior circulation stroke(AIS) who underwent MT between January 2016 and September 2022. Radiographic HC was identified on post-operative imaging. Asymptomatic hemorrhage was defined as no acute neurologic decline attributable to imaging findings. Baseline characteristics, technical aspects, and outcomes were compared between aHC and no HC groups. Logistic regression and multivariate analysis were performed. Results 615 patients underwent MT for AIS, of which 496 met inclusion criteria. 235 (47.4%) patients had evidence of aHC. Diabetes mellitus (OR 1.59; 95% CI 1.06 – 2.41; p=0.03), hyperglycemia (OR 1.01; 95% CI 1.00 – 1.01; p=0.002), greater number of passes (OR 1.14; 95% CI 1.00 – 1.31; p=0.05), and longer time to reperfusion (OR 1.02; 95% CI 1.00 – 1.05; p=0.05) were associated with aHC. Patients with aHC were significantly more likely to require rehabilitation, whereas those without HC were more likely to discharge home (p<0.001). There were no significant differences in long-term outcomes. Conclusion HC occurred in up to half of patients who underwent MT for AIS, of which the majority were clinically asymptomatic. Despite clinical stability, aHC was significantly associated greater need for inpatient rehabilitation. Predictors of aHC included hyperglycemia and longer time to reperfusion.