Sheng Z, et al. - Among prospectively enrolled 335 patients with ST-segment elevation myocardial infarction (STEMI) and 53 healthy controls, researchers investigated the link between trimethylamine N-oxide (TMAO) levels and the coronary atherosclerotic burden in STEMI patients. The number of diseased coronary arteries and the SYNTAX score were determined in order to quantify coronary atherosclerotic burden. Patients with STEMI and healthy controls had median TMAO levels 2.18 μM and 1.23 μM, respectively. Remarkably higher TMAO levels were detected in the multivessel disease group vs in the single-vessel disease group (p < 0.001) and in the group with intermediate-high SYNTAX scores (SYNTAX score ≥ 23) vs in the group with low SYNTAX scores (SYNTAX score ≤ 22) (p < 0.001). Both a high SYNTAX score and the presence of multivessel disease were predicted by elevated TMAO levels, as seen in the ordinal logistic regression analysis adjusted for traditional risk factors. Overall, plasma TMAO levels were found to be related to a high coronary atherosclerotic burden in patients with STEMI.