Adhesive properties of aortic semilunar valve and atherosclerotic plaques in patients with calcific aortic stenosis

The objective of the paper is to study the source mechanisms of the primary nucleus calcification in the matrix of the aortic semilunar valve and to determine the adhesive properties of the endothelial surface, and subendothelial structures of aortic semilunar valve and atherosclerotic aortic plaques. Materials and Methods. We studies 10 aortic valves and 10 parts of the aortic root (including areas with atherosclerotic plaques in the atheromatosis stage without wall damage) taken from patients without cardiac disorders, and 16 aortic valves retrieved intraoperatively from patients with severe aortic stenosis. The chemical composition of aortic calcium deposits was studied using XRD analysis. The study of adhesive properties of aortic leaflets and aortic atherosclerotic plaques to hydroxyapatite (HA) particles was conducted by means of atomic force microscopy and specialized probes with hydroxyapatite structures. The study of the chemical composition of aortic calcium deposits determined that they consisted of hydroxyapatite. It was shown that the endothelium adhesion force of the aortic root toward calcium phosphate increased 4 times if an atherosclerotic plaque was formed in this area, which denoted endothelial dysfunction. If endothelium was damaged adhesion force of subendothelial space increased 14-23 times. Conclusion. The results obtained demonstrate pathogenetic value of adhesive changes of endothelium and subendothelial structures in the development of calcified aortic stenosis. The suggested method of atomic force microscopy and specialized probes with hydroxyapatite structures helps to simulate the processes of ectopic calcification of the aortic valve.