[Trajectory of platelet changes following endovascular abdominal aortic aneurysm repair and its relationship with postoperative adverse events].

<b>Objective:</b> To investigate the dynamic trajectories of platelet (PLT) changes following endovascular aneurysm repair (EVAR) for abdominal aortic aneurysm (AAA) and analyze their association with postoperative adverse events. <b>Methods:</b> This retrospective study included patients with AAA who underwent EVAR at the Department of Vascular Surgery, Changhai Hospital of the Naval Medical University, between January 2000 and February 2024. Latent class growth modeling (LCGM) and growth mixture modeling (GMM) were employed to identify distinct PLT trajectory patterns relative to baseline levels within seven days postoperatively. Logistic regression was conducted to assess the association between PLT trajectory groups and postoperative adverse events. The Kaplan-Meier survival analysis was performed to evaluate the occurrence of adverse events within 30 days postoperatively, and the log-rank test was employed for comparsion between groups. <b>Results:</b> A total of 1 911 patients were included, comprising 1 602 males and 309 females, with a mean age of (71.37±9.32) years. LCGM combined with GMM identified four distinct PLT trajectory groups: severe decline group (<i>n</i>=114), moderate decline group (<i>n</i>=492), mild decline group (<i>n</i>=1 141), and increase (<i>n</i>=164) group. After adjusting for confounding factors, logistic regression confirmed that patients in the severe decline group (<i>OR</i>=2.23, <i>95%CI</i>:1.34-3.69) and moderate decline group (<i>OR</i>=1.81, <i>95%CI</i>:1.34-2.46) had a significantly increased risk of adverse events compared with the mild decline group, while no significant difference was observed in the increase group (<i>P</i>>0.05). Kaplan-Meier survival analysis demonstrated that, compared with the mild decline group, both the severe decline group (log-rank χ²=27.65, <i>P</i><0.001) and the moderate decline group (log-rank χ²=22.97, <i>P</i><0.001) had a significantly higher risk of adverse events [30.7% (35/114) and 22.4% (110/492) vs 13.7% (156/1 141)]. <b>Conclusion:</b> The dynamic trajectories of PLT following EVAR exhibit significant heterogeneity, patients with a moderate or severe postoperative decline in PLT count had a significantly increased risk of adverse events.