Omega-3 fatty acids from fish oil have been associated with beneficial cardiovascular effects but their role in modifying cardiac structures and tissue characteristics in patients who have suffered an acute myocardial infarction (MI) while receiving current guideline-based therapy remains unknown.
In a multicenter, double-blind, placebo-controlled trial, participants presenting with an acute MI were randomized 1:1 to 6-months of high-dose omega-3 fatty acids (n=178) or placebo (n=180). Cardiac magnetic resonance imaging was used to assess cardiac structure and tissue characteristics at baseline and following study therapy. The primary study endpoint was change in left ventricular systolic volume index (LVESVI). Secondary endpoints included change in non-infarct myocardial fibrosis, LVEF, and infarct size.
By intention-to-treat analysis, patients randomized to omega-3 fatty acids experienced a significant reduction of LVESVI (−5.8%, P=0.017), and non-infarct myocardial fibrosis (−5.6%, P=0.026) compared with placebo. Per-protocol analysis revealed that those subjects who achieved the highest quartile increase in RBC omega-3 index experienced a 13% reduction in LVESVI as compared with the lowest quartile. In addition, patients in the omega-3 fatty acid arm underwent significant reductions in serum biomarkers of systemic and vascular inflammation and myocardial fibrosis. There were no adverse events associated with high-dose omega-3 fatty acid therapy.