Till Örebro universitet

BACKGROUND: Lipidomics, the comprehensive profiling of circulating lipid species, has emerged as a powerful tool to investigate metabolic alterations underlying coronary atherosclerosis. Understanding the mechanisms driving high-risk vulnerable plaque formation and progression to myocardial infarction remains a key therapeutic priority. This study investigates associations between circulating lipid metabolites and imaging-defined features of vulnerable coronary plaque.

METHODS: Following revascularization, patients with myocardial infarction underwent 3-vessel coronary artery imaging with near-infrared spectroscopy and intravascular ultrasound to assess nonflow-limiting plaques for lipid core burden index and plaque burden. Multivariable models evaluated associations between 424 lipid metabolites in plasma, quantified by mass spectrometry, pan-coronary lipid, pan-coronary plaque burden, and high-risk vulnerable plaque measures (maximum lipid core burden index within any 4-mm segment across the entire lesion ≥324.7 and plaque burden ≥70%) in 877 patients. Findings were validated in the SCAPIS study (Swedish Cardiopulmonary Bioimage Study) using coronary computed tomography angiography-based measures of coronary artery calcium score and segment involvement score.

RESULTS: We identified 156 significant associations (P<0.05) between lipid metabolites and coronary plaque characteristics across 39 metabolic pathways. Sphingomyelins were inversely associated with all plaque metrics, and 1-palmitoyl-2-oleoyl-GPE (16:0/18:1), a phosphatidylethanolamine, was positively associated with all plaque metrics. After correcting for multiple testing, 27 lipid species across 7 pathways remained significant (q<0.05). The majority were linked to pan-coronary lipid burden, with the strongest inverse association observed for sphingomyelin d18:1/22:1, d18:2/22:0, and d16:1/24:1. Similar inverse patterns were seen for select dihydrosphingomyelins and fatty acid dicarboxylates. In contrast, 1-palmitoyl-2-oleoyl-GPE (16:0/18:1) remained positively associated with pan-coronary lipid. In the SCAPIS validation cohort, 19 of the 27 significant lipid associations were successfully replicated (q<0.05).

CONCLUSIONS: This study is the first to demonstrate that sphingomyelins are negatively and 1-palmitoyl-2-oleoyl-GPE (16:0/18:1) positively associated with vulnerable coronary plaque features based on multimodality intracoronary imaging in patients with myocardial infarction. Moreover, these associations were validated in a large cohort using coronary computed tomography angiography-derived measures of plaque burden. These novel results may enable the development of new diagnostic and therapeutic strategies.