Abstract 20008: Oxolipidomic Analysis of Calcific Stenotic Human Aortic Valves: Correlation of Oxidized Phosphatidylcholine and Lysophosphatidic Acid With Aortic Valve Gradient

Introduction: Aortic valve stenosis (AVS) is the most common heart valvulvar pathology seen in the western world. The pathological mechanism of AVS is still unclear. Recent studies suggest elevated plasma Lp(a) concentrations are associated with increased risk of developing AVS. Lp(a) is the primary transporter of oxidized phosphatidylcholines (OxPCs). It also binds autotaxin, an enzyme that converts lysophosphatidylcholine to lysophosphatidic acid (LPA), which has been postulated to induce valve calcification. The goal of this study was to determine the levels of OxPC and LPA in stenotic human aortic valves and to investigate their correlation to mean transvalvular gradient. Methods: Human aortic valves were obtained from 14 patients (mean age 71±9 years) at the St. Boniface General Hospital in Winnipeg, Canada undergoing aortic valve replacement surgery. Tissue lipids were extracted from aortic valves and OxPC and LPA content was measured via liquid chromatography coupled to electrospray ionization tand...