Trajectory Groups of 72-Hour Heart Rate After Mechanical Thrombectomy and Outcomes

Background and Purpose: Elevated heart rate (HR) after mechanical thrombectomy (MT) was associated with an increased risk of adverse outcomes. However, optimal HR management after MT remains unclear. This study aimed to identify patient subgroups with distinct HR trajectories after MT and explore their association with outcomes.
Methods: Acute ischemic stroke patients undergoing MT therapy were prospectively recruited from July 2020 to December 2022. Their heart rate indicators were collected every hour for 72 hours after MT procedure. Latent variable mixture modeling was used to separate subjects into five groups with distinct HR trajectories. The primary outcome was poor functional outcome (mRS score > 2) at 3 months. Additional outcome was all-cause mortality (mRS score = 6) at 3 months.
Results: A total of 224 patients with large vessel occlusion were enrolled, with a mean age of 65.2+14.0 years. Eighty-seven patients had a good functional outcome, and 137 patients had a poor functional outcome. Five distinct HR trajectories were observed: low (19.2%), moderate (33.0%), rapidly stabilized HR group (20.5%), persistently high HR group (21.0%), and very high HR group (6.3%). After adjusting for potential confounders, the HR trajectory group was independently associated with poor functional outcome at 3 months (P for interaction = 0.022). The risk of having poor functional outcome was increased in the rapidly stabilized HR group (odds ratio, 3.18 [95% confidence interval, 1.10– 9.19]), the persistently high HR group (odds ratio, 5.55 [95% confidence interval, 1.72– 17.87]) and very high HR group (odds ratio, 18.32 [95% confidence interval, 2.20– 95.52]) but not in the moderate group (odds ratio, 1.50 [95% confidence interval, 0.61– 3.69]), when compared with the low HR group. No significant association was found between trajectory group and 3-month all-cause mortality.
Conclusion: HR during the first 72 hours after MT may be categorized into distinct trajectory groups, which differ in relation to poor functional outcome event risks. The findings may help to recognize potential candidates for future HR control trials.

Key words: ischemic stroke, heart rate trajectory, mechanical thrombectomy, outcome