(P041) SEX DIFFERENCES IN PLASMA LIPIDOME IN PATIENTS WITH STEMI UNDERGOING PCI

Background: Rapid coronary reperfusion using primary percutaneous coronary intervention (PCI) is the corner stone of therapy for patients presenting with ST elevation myocardial infarction (STEMI) that restores blood flow and limits infarct size. Paradoxically, however, PCI in itself can induce additional myocardial injury, termed reperfusion injury. We have recently shown that there are large shifts in plasma lipidome post PCI correlating with clinical outcomes. Given the differences in outcomes in males vs females post reperfusion, we aim to better understand the sex differences in the lipidome shift post PCI.

METHODS AND RESULTS: 126 patients (97 males, 29 females) undergoing PCI for STEMI in a tertiary centre underwent venous blood sampling with subsequent semi-targeted Liquid Chromatography with Tandem Mass Spectrometry (LC/MS/MS) to determine 350 lipid species. Samples were taken pre-PCI (T0), then 2 hours post PCI (T1) and 24 hours (T2) post successful reperfusion.
Each lipid class and individual circulating lipid species were compared between males and females at each time point using statistical analysis, to determine the similarities and differences in plasma lipidome shifts in ACS between sexes.
At T0, pre-PCI, total free fatty acids (FFA) and total phosphatidylinositol (PI) were significantly elevated in females compared with males (p=0.012, p=0.018 respectively). At T1, post-PCI, total PI remained significantly more elevated in females than males (p=0.001), as did total phosphatidylethanolamine (PE) (p=0.003) and total acylcarnitine (p=0.006). Together there were 20 distinct lipid species that showed difference between females and males undergoing PCI, with the largest differences in the 3 fold increase in PI 40:6 and PI 38:6, which are both polyunsaturated inositol phospholipids, in the female group. Also polyunsaturated FFA 22:6 and 18:3 showed significant increase in females as compared to males post reperfusion.

Conclusion: Our analysis suggests there are differences in lipidomics shift between males and females in response to myocardial reperfusion. The higher levels of circulating FFA in females in the earlier timepoint T0, followed by a parallel increase of acylcarnitine in females at a later timepoint T1, suggest differences in myocardial metabolic response to reperfusion injury. Comparing the plasma lipidome between males and females before and after reperfusion allow for better understanding of sex specific response to ischemia and reperfusion during acute myocardial infarction.