Trans-myocardial omega-3 fatty acid gradient in coronary microvascular dysfunction

BACKGROUND: Cardiac remodeling is a process mediated, in part, by 18-hydroxyeicosapentaenoic acid (HEPE), a metabolite of the omega-3 polyunsaturated fatty acid, eicosapentaenoic acid (EPA). We hypothesized that trans-myocardial levels of 18-HEPE could inform the pathophysiologic processes involved in heart failure with preserved ejection fraction (HFpEF). METHODS: We measured the concentration of 18-HEPE and EPA in trans-myocardial plasma samples from 10 subjects enrolled in The Women’s Ischemia Syndrome Evaluation [WISE] Mechanisms of Coronary Microvascular Dysfunction Leading to Pre-HFpEF project. RESULTS: Concentrations of 18-HEPE were significantly lower in coronary venous compared to the aortic plasma (270.5 pg/mL [212.8–480.8] vs. 430.5 pg/mL [299.5–655.8], p = 0.0039). There was a significant correlation between the concentrations of coronary venous EPA and aortic 18-HEPE (r = 0.94, p = 0.0002), and aortic EPA and aortic 18-HEPE (r = 0.82, p = 0.0058). CONCLUSIONS: Results of this small pilot study support the suggestion that 18-HEPE is synthesized outside the heart and utilized within the myocardial bed.