Share This Article:

Study on the structure and composition of aortic valve calcific deposits. etiological aspects

Full-Text HTML Download Download as PDF (Size:651KB) PP. 19-25
DOI: 10.4236/jbpc.2011.21003    3,797 Downloads   7,469 Views   Citations

ABSTRACT

The structures and chemical compositions of valve calcific deposits were investigated. The deposits was chosen arbitrarily and subjected to chemical analysis, observation with scanning microscope, semi-quantitative determination of Ca, Mg, Na, K, P and C elements by energy dispersive X-ray, X-ray diffraction and Fourier transform infrared spectroscopy carried out. These deposits were found to have non-uniform internal structures composed of layers of a structureless aspidinic inorganic material, substantial amounts of voluminous organic material and in a few samples small spheres were also present. Two groups of deposits with distinctly different chemical compositions were identified: one group with a low Ca/P molar ratio (1.59) and the other group with a high (1.82) Ca/P molar ratio. The deposits belonging to the group with a low Ca/P molar ratio contain higher concentration of magnesium and consist of increased amount of amorphous calcium phosphate. The deposits with a high Ca/P molar ratio contain low concentration of magnesium and consist predominantly of carbonated hydroxyapatite. The inorganic material was identified as a poorly crystalline carbonate hydroxyapatite containing molecular water of the average formula Ca9.1Mg0.4(Na,K)(PO4)5.8(CO3)0.3(OH)2. The actual chemical composition of the apatitic solid phase varies not only from deposit to deposit but also within the same deposit. The non-uniform internal structure of the deposits, the occasional presence of spherical particles and the variable point composition of the individual deposits indicate that their formation did not proceed under more or less constant conditions.

Conflicts of Interest

The authors declare no conflicts of interest.

Cite this paper

Prieto, R. , Gomila, I. , Söhnel, O. , Costa-Bauza, A. , Bonnin, O. and Grases, F. (2011) Study on the structure and composition of aortic valve calcific deposits. etiological aspects. Journal of Biophysical Chemistry, 2, 19-25. doi: 10.4236/jbpc.2011.21003.

References

[1] Tomazic, B.B., Brown, W.E. and Schoen, F.J. (1994) Physicochemical properties of calcific deposits isolated from porcine bioprosthetic heart valves removed from patients following 2-13 years function. Journal of Biomedical Materials Research Part A, 28(1), 35-47. doi:10.1002/jbm.820280106
[2] Tomazic, B.B., Edwards, W.D. and Schoen, F.J. (1995) Physicochemical characterization of natural and bioprosthetic heart valve calcific deposits: implications for prevention. The Annals of Thoracic Surgery, 60(Suppl. 2), S322-S327. doi:10.1016/0003-4975(95)00205-Y
[3] Mikroulis, D., Mavrilas, D., Kapolos, J., Koutsoukos P.G. and Lolas, C. (2002) Physicochemical and microscopical study of calcific deposits from natural and bioprosthetic heart valves. Comparison and implications for mineralization mechanism. Journal of Materials Science: Materials in Medicine, 13(9), 885-889. doi:10.1023/A:1016556514203
[4] Delonge, C., Lawford, P.V., Habesch, S.M. and Carolan, V.A. (2007) Characterization of the calcification of cardiac valve bioprostheses by environmental scanning electron microscopy and vibrational spectroscopy. Journal of Microscopy, 228(1), 62-77. doi:10.1111/j.1365-2818.2007.01824.x
[5] Gilinskaya, L.G., Grigorieva, T.N., Okuneva, G.N. and Vlasov, Yu.A. (2003) Investigation of phatogenic mineralization on human heart valves. I. Chemical and phase composition. Journal of Structural Chemistry, 44(4), 622-631. doi:10.1023/B:JORY.0000017938.42883.9f
[6] Gilinskaya, L.G., Okuneva, G.N. and Vlasov, Yu.A. (2003) Investigation of pathogenic mineralization on human heart valves. II. ESR spectroscopy. Journal of Structural Chemistry, 44(5), 813-820. doi:10.1023/B:JORY.0000029819.16581.8a
[7] Gilinskaya, L.G., Rudina, N.A., Okuneva, G.N. and Vlasov, Yu.A. (2003) Pathogenic mineralization on human heart valves. III. Electron microscopy. Journal of Structural Chemistry, 44(6), 1038-1045. doi:10.1023/B:JORY.0000034811.28903.9b
[8] Michaylova, V. and Ilkova, P. (1971) Photometric determination of micro amounts of calcium with arsenazo III. Analytica Chimica Acta, 53(1), 194-198. doi:10.1016/S0003-2670(01)80088-X
[9] Chauman, U.P.S. and Ray Sarkar, B.C. (1969) Use of calmagite for the determination of traces of magnesium in biological materials. Analytical Biochemistry, 13(1), 70-80. doi:10.1016/0003-2697(69)90105-5
[10] Martin, M., Celi, L. and Barberis, E. (1999) Determination of low concentrations of organic phosphorus in soil solution. Communications in soil science and plant analysis, 30(13-14), 1909-1917. doi:10.1080/00103629909370341
[11] Pleshko, N., Boskey, A. and Mendelsohn, R. (1991) Novel infrared spectroscopic method for the determination of crystallinity of hydroxyapatite minerals. Biophysical Journal, 60(4), 786-793. doi:10.1016/S0006-3495(91)82113-0
[12] Kapolos, J. and Koutsoukos, P.G. (1999) Formation of calcium phosphate in aqueous solutions in the presence of carbonate ions. Langmuir, 15(19), 6557-6562. doi:10.1021/la981285k
[13] Ito, A., Maekawa, K., Tsutsumi, S., Ikazaki, F. and Tateishi, T. (1997) Solubility product of OH-carbonated hydroxyapatite. Journal of Biomedical Materials Research Part A, 36(4), 522-528. doi:10.1002/(SICI)1097-4636(19970915)36:4<522::AID-JBM10>3.0.CO;2-C
[14] Tomazic, B.B. (2001) Physicochemical principles of cardiovascular calcification. Clinical Research in Cardiology, 90(Suppl. 2), 1168-1180.

  
comments powered by Disqus

Copyright © 2018 by authors and Scientific Research Publishing Inc.

Creative Commons License

This work and the related PDF file are licensed under a Creative Commons Attribution 4.0 International License.