342 tmao plasma levels predict recurrent ischemic events in survivors of myocardial infarction

Abstract Background Recent studies have highlighted a direct link between dietary nutrients, microbiota and cardiovascular disease (CVD). In this context, trimethylamine-N-oxide (TMAO), a metabolite derived from the intestinal microbiota, stands out, paving its way as one of the important biomarkers associated with atherosclerosis, increased risk of CVD, recurrent events and adverse outcomes. Methods 81 patients who survived acute myocardial infarction (AMI), (both STEMI 50 / NSTEMI 31) were enrolled in this study together with 10 healthy individuals. Further, we evaluated the relationship between plasma TMAO levels and cardiovascular events during the follow-up. The measurement of plasma levels of TMAO was performed using liquid chromatography-tandem mass spectrometry (LC-MS). Results The median plasma concentration of TMAO were significantly higher in patients with AMI compared with healthy control (1.62 (1.37–2.25) µM. vs 0.55 (0.35–0.74) µM, p < 0.0001). During a median follow-up of 61.74 (59.34–64.24) months, 10 out of 81 patients (12.3%) had a re-infarction. Patients who had another ischemic event had higher TMAO values compared with individuals who did not (2.29 (1.60–6.49) µM vs 1.60 (1.34–2.09) µM, p = 0.026). Further, TMAO values positively correlate with CRP, a pro-inflammatory marker. However, at multivariate Cox regression analysis, plasma TMAO values were not predictive of re-infarction. Conclusions The data of our pilot study show that higher TMAO values are associated with the risk of recurrent ischemic event. A future prospective study, including larger cohort is necessary to analyze this issue.