Objective: We conducted a clinical trial to examine the effect of ω-3 fatty acids in patients with cardiac syndrome X (CSX). We aimed to evaluate the potential impact of ω-3 fatty acids on endothelial function, oxidative stress, and symptom relief in the CSX.
Methods and results: Eighteen patients with CSX were enrolled according to a double-blind, randomized, placebo-controlled design. Patients were randomized to ω-3 fatty acids (1440 mg/day, n=8) or placebo (n=10) for 4 months. We assessed plasma levels of malondialdehyde (MDA), endothelium-dependent vasodilatation [flow-mediated dilatation (FMD)], endothelium-independent vasodilatation [nitroglycerin-mediated dilatation (NMD)], and status of symptom [score with Seattle Angina Questionnaire (SAQ)] before and after the treatment. After 4 months, patients who were treated with ω-3 fatty acids showed significant increases in the FMD (from 47±48 to 104±23%, P<0.05) and NMD (from 51±53 to 93±35%, P<0.05) values, and significant decreases in the plasma MDA levels (4.4±0.86 to 3.35±0.33 µmol/l, P=0.012). SAQ scores were increased significantly in both groups (from 60±14 to 73±15%, P<0.05 placebo, from 67±10 to 81±9%, P<0.05 treatment group). NMD was correlated negatively with the plasma MDA levels.
Conclusion: Four months of therapy with a moderate dose of ω-3 fatty acids improved the endothelial function and reduced oxidative stress in patients with CSX.