Decreased LF/HF ratio is associated with worse outcomes in patients who received mechanical thrombectomy under general anesthesia for emergent large vessel occlusion: a retrospective study

Background and purpose We aimed to determine whether heart rate variability (HRV) was correlated to long-term outcome in patients who received mechanical thrombectomy (MT) under general anesthesia for emergent large vessel occlusion (ELVO). Methods Data from 106 patients receiving MT under general anesthesia to treat ELVO between January 1, 2017 and December 31, 2019 were collected in a multicenter chart review. Univariate analysis, Chi-square test, and bivariate logistic regression were performed to assess the correlations between preoperative risk factors such as HRV and long-term outcome (as indicated by the modified Rankin score [mRS] at 90 days after MT). Results Bivariate logistic regression revealed that decreased LF/HF (low frequency/high frequency in HRV) ratio was correlated with unfavorable functional outcome as indicated by mRS >= 2 (odds ratio [OR], 0.650; 95% confidence interval [CI], 0.157-0.839;p= 0.018), and functionally dependent outcome as indicated by mRS >= 3 (OR, 0.704; 95% CI, 0.360-0.914;p= 0.021). It was also found that ELVO in the right anterior circulation was correlated with lower LF/HF ratio, as compared with ELVO in the contralateral side (p< 0.05). Conclusion Our retrospective study demonstrated that worse outcome in patients with ELVO who received MT under general anesthesia induced autonomic changes and that decreased LF/HF ratio.