Blood Pressure Trajectory Groups and Outcome After Endovascular Thrombectomy: A Multicenter Study

Abstract

Background: Elevated blood pressure after endovascular thrombectomy (EVT) has been associated with an increased risk of hemorrhagic transformation and poor functional outcomes. However, the optimal hemodynamic management after EVT remains unknown, and the blood pressure course in the acute phase of ischemic stroke has not been well characterized. This study aimed to identify patient subgroups with distinct blood pressure trajectories after EVT and study their association with radiographic and functional outcomes.

Methods: This multicenter retrospective cohort study included consecutive patients with anterior circulation large-vessel occlusion ischemic stroke who underwent EVT. Repeated time-stamped blood pressure data were recorded for the first 72 hours after thrombectomy. Latent variable mixture modeling was used to separate subjects into five groups with distinct postprocedural systolic blood pressure (SBP) trajectories. The primary outcome was functional status, measured on the modified Rankin Scale 90 days after stroke. Secondary outcomes included hemorrhagic transformation, symptomatic intracranial hemorrhage, and death.

Results: Two thousand two hundred sixty-eight patients (mean age [±SD] 69±15, mean National Institutes of Health Stroke Scale 15±7) were included in the analysis. Five distinct SBP trajectories were observed: low (18%), moderate (37%), moderate-to-high (20%), high-to-moderate (18%), and high (6%). SBP trajectory group was independently associated with functional outcome at 90 days (P<0.0001) after adjusting for potential confounders. Patients with high and high-to-moderate SBP trajectories had significantly greater odds of an unfavorable outcome (adjusted odds ratio, 3.5 [95% CI, 1.8-6.7], P=0.0003 and adjusted odds ratio, 2.2 [95% CI, 1.5-3.2], P<0.0001, respectively). Subjects in the high-to-moderate group had an increased risk of symptomatic intracranial hemorrhage (adjusted odds ratio, 1.82 [95% CI, 1-3.2]; P=0.04). No significant association was found between trajectory group and hemorrhagic transformation.

Conclusions: Patients with acute ischemic stroke demonstrate distinct SBP trajectories during the first 72 hours after EVT that have differing associations with functional outcome. These findings may help identify potential candidates for future blood pressure modulation trials.

Keywords: blood pressure; brain ischemia; hemorrhage; intracranial hemorrhage; thrombectomy.

Figure 1:

SBP Trajectories 72 Hours after EVT Five BP trajectories were identified over the first 72 hours after EVT. Time point zero corresponds to recanalization time or, for non-recanalized subjects, end of EVT. Solid lines represent mean observed BP and shaded areas represent the 95% confidence interval.

Figure 2:

90-day mRS by SBP Trajectory The distribution of the modified Rankin Scale (mRS) at 90 days by SBP trajectory group. Higher mRS scores and darker shades correspond to more unfavorable functional outcomes. The dashed line demarcates the border of favorable (mRS 0–2) versus unfavorable (mRS 3–6) functional outcome. Higher rates of unfavorable functional outcome are observed in higher SBP trajectory groups.

Figure 3:

Adjusted Odds Ratio of Clinical and Radiographic Outcomes by SBP Trajectory Adjusted odds ratios (midpoints) with 95% confidence intervals (error bars) from the analysis of functional and radiographic outcomes by post-procedural 72-hour SBP trajectory group. An asterisk above the error bars indicates a statistically significant difference between the indicated trajectory group and reference low trajectory group. (A) Odds of developing an unfavorable functional outcome at 90 days (B) Odds of developing an unfavorable functional outcome at discharge (C) Odds of developing HT (D) Odds of developing sICH. The low trajectory group serves as the reference.