Role of endothelial cell denudation and smooth muscle cell dedifferentiation in neointimal formation of human vein grafts after coronary artery bypass grafting: therapeutic implications

摘要: OBJECTIVE—To provide better insights into the genesis of neointimal thickening in human vein grafts early after surgery. DESIGN—Retrospective study. SETTING—Tertiary referral centre. SUBJECTS—18 distal anastomotic sites patent grafts, obtained at necropsy from eight patients who died over differing periods (ranging two days to nine months) procedure. MAIN OUTCOME MEASURES—Immunohistochemical evaluation smooth muscle cell phenotype modulation relation proliferative activity. RESULTS—The earliest changes are characterised by loss surface lining endothelial cells and insudation blood corpuscular elements admixed with fibrin-platelet thrombus. At injury vimentin positive actin negative spindle shaped appear intima, while related pre-existent media shows focal absence cells. Proliferative activity colocalises these sites. With time distinct occurs, associated disappearance a phenotypic shift cells. CONCLUSIONS—The observation that luminal denudation, intima elements, occurs very stages suggests phenomena responsible for observed dedifferentiation cells, known be prerequisite proliferation evolution intimal thickening. It is likely, therefore, platelet released growth factors play pivotal role, which thus may target preventive pharmacological intervention. Keywords: proliferation; graft stenosis; derived factor; receptor inhibitors