Natural and prosthetic heart valve calcification: morphology and chemical composition characterization.
Calcification is the most common cause of damage and subsequent failure of heart valves. Although it is a common phenomenon, little is known about it, and less about the inorganic phase obtained from this type of calcification. This article describes the scanning electron microscopy (SEM)/energy dispersive X-ray spectroscopy and Ca K-edge X-ray absorption near edge structure (XANES) characterization performed in natural and bioprosthetic heart valves calcified in vivo (in comparison to in vitro-calcified valves). SEM micrographs indicated the presence of deposits of similar morphology, and XANES results indicate, at a molecular level, that the calcification mechanism of both types of valves are probably similar, resulting in formation of poorly crystalline hydroxyapatite deposits, with Ca/P ratios that increase with time, depending on the maturation state. These findings may contribute to the search for long-term efficient anticalcification treatments.
Weska
Raquel F
RF
School of Chemical Engineering, University of Campinas, UNICAMP, Campinas, SP, Brazil.
Aimoli
Cassiano G
CG
Nogueira
Grínia M
GM
Leirner
Adolfo A
AA
Maizato
Marina J S
MJ
Higa
Olga Z
OZ
Polakievicz
Bronislaw
B
Pitombo
Ronaldo N M
RN
Beppu
Marisa M
MM
D002114:Calcinosis / Q000473:pathology*; D009202:Cardiomyopathies / Q000473:pathology*; D006350:Heart Valve Prosthesis; D006351:Heart Valves / Q000473:pathology*; D006801:Humans; D008855:Microscopy, Electron, Scanning; D011475:Prosthesis Failure; D013052:Spectrometry, X-Ray Emission