Investigating tissue factor pathway inhibitor and other protease and protease inhibitors and their association with major adverse aortic events in patients with abdominal aortic aneurysm.

Background: Abdominal aortic aneurysm (AAA) is characterized by the proteolytic breakdown of the extracellular matrix, leading to dilatation of the aorta and increased risk of rupture. Biomarkers that can predict major adverse aortic events (MAAEs) are needed to risk stratify patients for more rigorous medical treatment and potential earlier surgical intervention.

Objectives: The primary objective was to identify the association between baseline levels of these biomarkers and MAAEs over a period of 5 years.

Methods: Baseline levels of 3 proteases (matrix metalloproteinases 7, 8, and 10) and 3 protease inhibitors (tissue factor pathway inhibitor [TFPI], SerpinA12, SerpinB3) were investigated. Plasma levels of these biomarkers were quantified in 134 patients with AAA and 134 matched controls. Patients were followed for a 5-year period during which MAAEs were documented. The association between these markers and MAAEs was evaluated using Cox regression and Kaplan-Meier survival curves.

Results: TFPI was significantly elevated in patients with AAA and significantly associated with MAAE during the 5-year period (hazard ratio, 1.52; 95% CI, 1.15-2.01;  = .003) after adjusting for covariates. Kaplan-Meier survival analyses demonstrated that patients in the high TFPI group (defined as plasma levels >25.961 ng/mL) had significantly reduced freedom from the need for aortic repair and MAAEs.

Conclusion: These findings suggest that TFPI may serve as a valuable prognostic marker for the risk of MAAEs within 5 years in patients with AAA, potentially offering new tools for the medical management of patients with AAA.