ABSTRACT
BACKGROUND AND AIMS: Recent epidemiological studies have showed that excessive intake of trans fatty acids (TFA) can be a residual risk for the development of coronary artery disease (CAD) even under medical management, including statins. This study aimed at investigating the association between lipid profile, including serum TFA concentration, and plaque vulnerability using optical coherence tomography (OCT). METHODS: The level of serum elaidic acid, a major TFA component, was measured using gas chromatography in 161 consecutively enrolled patients with CAD under guideline-directed risk factor management. OCT was performed to evaluate morphological features of angiographic intermediate stenosis (30% < diameter of stenosis <70%). OCT data were also used to measure lipid index (LI), defined as mean lipid arc multiplied by lipid length, and determine the presence of thin-cap fibroatheroma (TCFA), defined as a lipid-rich plaque with the smallest fibrous cap thickness <65 µm and the maximal arc >90°. RESULTS: Among 190 lesions assessed using OCT, 49 TCFAs were detected. In patients with at least one TCFA lesion, levels of elaidic acid (12.9 ± 4.9 vs. 10.3 ± 4.3 µmol/L, p = 0.001), triglycerides (169 ± 81 vs. 130 ± 60 mg/dL, p = 0.005), and remnant-like particle cholesterol (10.4 ± 6.5 vs. 7.7 ± 4.7 mg/dL, p = 0.005) were higher than in those without TCFAs. Generalized estimating equations identified elaidic acid level as the independent risk factor of TCFA. LI had a positive correlation with elaidic acid level (r = 0.173, p = 0.025). CONCLUSIONS: TFA may affect plaque vulnerability in patients with CAD. Serum TFA concentration may represent another cardiovascular risk factor during conventional risk factor management.