Urinary 11‐Dehydro‐Thromboxane B2 as a Predictor of Acute Myocardial Infarction Outcomes: Results of Leukotrienes and Thromboxane In Myocardial Infarction (LTIMI) Study

BACKGROUND Urinary 11-dehydro-thromboxane (TX)B2 has been described as a potential predictive biomarker of major adverse cardiovascular events (MACEs) in high cardiac risk patients. This part of LTIMI (Leukotrienes and Thromboxane In Myocardial Infarction) study aimed to evaluate the relationship between 11-dehydro-TXB2 and MACEs in patients with acute myocardial infarction (AMI). METHODS AND RESULTS LTIMI was an observational, prospective study in 180 consecutive patients with AMI type 1 referred for primary percutaneous coronary intervention. On admission and at follow-up visits (1 month, 1 year), 11-dehydro-TXB2 was measured in urinary samples by using high-performance liquid chromatography-tandem mass spectrometry. The primary outcome was occurrence of composite MACEs during 1-year after AMI. Left ventricular ejection fraction was assessed in echocardiography on admission and at 1-year follow-up. Analyses of 11-dehydro-TXB2 (pg/mg creatinine) were performed on log-transformed data and expressed as median with IQR (Q1-Q3). 11-Dehydro-TXB2 level on admission was 7.39 (6.85-8.01) and decreased at 1 month (6.73, 6.27-7.12; P<0.001) and 1-year follow-up (6.37, 5.91-6.94; P<0.001). In univariate analysis, baseline 11-dehydro-TXB2 was higher in patients with MACEs (n=60; 7.73, 7.07-8.60) compared with those without MACEs (n=119; 7.28, 6.68-7.79; P=0.002). In multivariate regression model, 11-dehydro-TXB2 and 3 other variables (diabetes, multivessel disease, and left ventricular ejection fraction) were found to be best 1-year cumulative MACE predictors with odds ratio for 11-dehydro-TXB2 of 1.58 (95% CI 1.095-2.33; P=0.017) and area under the curve (in receiver operating characteristic analysis of 0.8). Baseline 11-dehydro-TXB2 negatively correlated with both left ventricular ejection fraction on admission (R=-0.21; P=0.006) and after 1 year (R=-0.346; P<0.001). CONCLUSIONS 11-Dehydro-TXB2 predicts 1-year cumulative MACEs in AMI patients and provides prognostic information on the left ventricular performance.