Improved endothelial dysfunction and decreased endothelial injury after transaortic valve implacement

Abstract

Purpose: Degenerative aortic valve stenosis is independently associated with endothelial dysfunction and increased endothelial injury. Circulating endothelial derived microparticles (EMPs) have been shown to be a marker of endothelial injury and are established as a prognostic marker of cardiovascular outcome. Therefore, we tested in patients with aortic valve stenosis, whether resolvement of the aortic valve stenosis improves endothelial dysfunction and decreases endothelial injury, as assessed by levels of EMPs. Methods: Endothelial function and circulating microparticles (MPs) were measured at a 3 month study period without transaortic valve implacement (TAVI) compared to a 3 month study period after TAVI. Of 81 patients included in the study, n=56 could be followed up completely. Measurements of endothelial function and number of circulating MPs were taken before and after each study period: Endothelial function was assessed as flow-mediated dilation (FMD) using ultrasound. MP subpopulations were discriminated by flow cytometry according to the expression of established surface antigens. The MP subpopulations were defined as follow: CD31+/CD41-, CD 144+ and CD 62E+ as EMPs, CD41+ as platelet-derived MPs (PMPs), and CD45+ as leucocytes derived MPs (LMPs). Results: Endothelial function increased and vascular injury (levels of EMPs) decreased at 3 month follow up after TAVI. Levels of LMPs also decreased. Levels of total MPs and PMPs did not change. Conclusion: Endothelial dysfunction improves and endothelial inury decreases after resolvement of the aortic valve stenosis by TAVI. Our study complements previously shown association indicating that aortic valve stenosis independently impairs endothelial function.