Abstract 16001: Relationship Between Serum n-3 to n-6 Poly-unsaturated Fatty Acid Ratios and Coronary Plaque Components Identified by iMap-Intravascular Ultrasound in Patients With Stable Angina Pectoris

Abstract

Background: Residual risk of cardiovascular disease exists even in patients achieving low-density lipoprotein cholesterol (LDL-C) goals. A low value of serum eicosapentaenoic acid to arachidonic acid (EPA/AA) ratio is well known to be associated with cardiovascular events. However, the association between serum EPA/AA ratio and coronary plaque components has not been fully investigated. Purpose: We evaluated the relationships between serum EPA/AA ratio and coronary plaque morphology on iMap-intravascular ultrasound (IVUS) which is a 40 MHz IVUS tissue characteristic system. Methods: We investigated 80 consecutive coronary culprit lesions with stable angina pectoris (SAP) patients, who underwent pre-intervention iMap-IVUS. All patients were divided into two groups; groups with higher values of the median EPA/AA ratio and lower values of the median EPA/AA ratio. We assessed the relationship between the two groups. Results: Median values of EPA, AA and EPA/AA ratio were 67.5 (44.3-100.3) μg/ml, 174.2 (145.5-202.9) μg/ml, and 0.38 (0.23-0.60). Patients in lower EPA/AA ratio group (<0.38) showed younger age (65±11 vs 70±6, p=0.02), more OMI patients (40 vs 18%, p=0.03), higher value of LDL-C (94.5±29.3 vs 80.9±26.5 mg/dl, p=0.03), lower ejection fraction (61.4±8.8 vs 65.4±7.2%, p=0.04), greater lesion plaque area (11.5±4.4 vs 9.6±4.4 mm2, p<0.05), compared with higher EPA/AA ratio group. In multivariate analysis, LDL-C value was an independent predictor of lower EPA/AA ratio (odds ratio 1.02, 95% confidence interval 1.00-1.04, p= 0.04). In lower LDL-C group (<70 mg/dl), EPA/AA inversely correlated with %-necrotic area and volume (r=-0.56, p=0.004, and r=-0.54, p=0.01), and positively correlated with %-fibrotic area and volume (r=0.57, p=0.003, and r=0.54, p=0.01), although EPA/AA ratio did not correlate with plaque components in higher LDL-C groups. In lower LDL-C group, for prediction of the highest %-necrotic volume tertile (>42.1%), cut-off value of EPA/AA ratio was 0.20 (sensitivity 50%, specificity 94%, area under the curve 0.77, p=0.02). Conclusion: serum EPA/AA ratio may be related to plaque components at the culprit site in SAP patients with low LDL-C values.