Enoxaparin Effectiveness: Correlating Anti-Factor Xa Activity Levels with Clinical Outcomes in Patients with Acute Coronary Syndrome

Abstract

Objectives: This study aimed to evaluate the effectiveness of enoxaparin in achieving therapeutic anti-Factor Xa activity levels and to assess their correlation with clinical outcomes among patients diagnosed with acute coronary syndrome (ACS). Methodology: A prospective cohort study was conducted on 65 adult patients (≥18 years) admitted with ACS. Enoxaparin dosing was individualized based on age, weight, and creatinine clearance, with anti-Factor Xa activity levels measured four hours after the third dose. Patients were monitored throughout hospitalization for major adverse cardiovascular events (MACE), bleeding, and other adverse reactions. Statistical analyses were performed using SPSS version 26.0, employing chi-square, ANOVA, and exact logistic regression where appropriate, with a significance threshold of p < 0.05. Results: Among the 65 participants, 38 (58.5%) were male, with a mean age of 59.5 ± 10.8 years. The mean creatinine clearance was 65.9 ± 18.2 mL/min, and diagnoses included NSTEMI (38.5%), STEMI (29.2%), and unstable angina (32.3%). Anti-Factor Xa levels were therapeutic (0.5–1.0 IU/mL) in 50 (76.9%), sub-therapeutic (<0.5 IU/mL) in 9 (13.8%), and supra-therapeutic (>1.2 IU/mL) in 6 (9.2%) patients. Sub-therapeutic levels were significantly associated with higher in-hospital MACE (p = 0.0016), while no significant correlation was found with bleeding or allergic reactions. Conclusion: Enoxaparin achieved therapeutic anti-Factor Xa activity in the majority of ACS patients, indicating effective anticoagulation. However, sub-therapeutic levels were strongly associated with an increased risk of in-hospital MACE, underscoring the clinical importance of regular anti-Factor Xa monitoring to optimize dosing and improve outcomes.