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The application of PIXE and micro-PIXE methods for the description of human aortic wall mineralization including its dynamics is presented. The data was collected both from human autopsy samples and from animal material. The mean concentrations of P, S, Cl, K, Ca, Fe, Cu, Zn, Br, Sr and Pb were determined in tissue samples and in the aortic wall sections. On the basis of PIXE results the following conclusion may be drawn: the concentrations of Ca, Zn, Sr and Pb increase while that of S, Cl and K contents decrease when the mineralization of the vessel wall (determined histochemically) develops. The micro-PIXE method enabled: (1) the determination of the elemental composition of both inorganic and organic materials in the sample, (2) the identification of different Ca—P compounds on the basis of the Ca/P ratio, (3) the investigations of the involvement of other elements in the development of mineralization process (4) the determination of the deposit radii on the basis of Ca concentration and (5) the generalized analysis on the inorganic deposit growth using mathematical description.

Marfan Syndrome and Bicuspid Aortic Valve (BAV) are characterized by the congenital/inherited alteration of the fibrillin proteins of aortic wall extracellular matrix, with higher incidence of aortic dissection/rupture even without aortic dilation. Therefore, early identification and treatment of aortic involvement could improve prognosis. The purpose of this study was to evaluate aortic elastic properties of BAV and Marfan Syndrome patients to identify an index of early aortic involvement. Methods: A Magnetic Resonance Imaging (MRI) study was performed on 38 BAV patients, 20 Marfan patients and 14 healthy volunteers as a control group. A high-resolution gradient-echo sequence was applied in the axial plane at the level of pulmonary artery bifurcation to evaluate aortic distensibility. Results: Aortic distensibility was significantly different among the three groups (ANOVA, p = 0.0001) and was sensibly reduced in BAV (0.0056 ± 0.0048 versus 0.025 ± 0.006 control group) and Marfan (0.0085 ± 0.006 versus 0.025 ± 0.006 control group). Intraobserver and interobserver reproducibility for diastolic measurements were 1.2% and 0.4% respectively and for systolic measurements, they were 1.1% and 0.3% respectively. Conclusion: In BAV or Marfan Syndrome patients, MRI evaluation of abnormal distensibility may provide a reliable index of early aortic involvement, even before aortic dilation occurs.