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Objectives: The problems in preparing (including cryopreservation) and implanting aortic valve allografts (AVAs) is widely elaborated, but some issues need explanation., Material and Methods: Twenty AVAs cryopreserved in dimethylsulphoxide/RPMI solution under -160°C for 1-15 years and 3 controls stored at +4°C up to 2 weeks, from 19 male and 4 female donors, aged 20-51, ±30.8 years, were examined using light (LM), digital (DM), and scanning electron microscopy (SEM), energy dispersion X-ray spectroscopy (EDS), and enzyme-linked immunosorbent assay immunoenzymatic tests (PECAM1, CD34)., Results: All AVAs were macroscopically correct. LM revealed normal structure of leaflets but massive endothelial decellularization (±59 cells remained on the surface of 5 mm scraps). DM and SEM demonstrated generally normal collagen structures, but local alterations, probably influenced by freezing-thawing (gaps, separated plates) or being initial phase of native degeneration (grains). EDS detected a little elevated calcium amount in 1 specimen only. The mean PECAM1 and CD34 concentrations were at similar low level in all probes., Conclusions: Fresh and cryopreservation technologies did not significantly influence the basic properties of AVA leaflets; however, massive endothelial decellularization was present in both groups. Therefore, no endocardial cell activity nor signs of inflammation were observed. These results were independent of donors' age and sex, processing technology, and time of storage of cryopreserved AVAs., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Aim: The 12 months' observation of body mass index (BMI) influence on natural course of aortic valve stenosis (AVS)., Patients: 60 AVS patients who did not agree for operational treatment were divided into group A (n = 15) with BMI 20-25, group B (n = 27) with BMI 25,01-30 and group C BMI > 30., Methods: Plasma Lp(a), total cholesterol, HDL-cholesterol, LDL-cholesterol, triglycerides and C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor (TNF-alpha) as well as titers of immunoglobulin (Ig) class G, A, M against chlamydia pneumoniae were measured every 12 months. Echo-cardiographic evaluation of aortic valve was also done every 12 months., Results: Means serum CRP at 12 month was the highest in group C. No differences in mean serum TNF-alpha and IL-6 levels as well as in Ig titers between groups A, B, C were found. At 12 month of observation HDL/total cholesterol ratio as well as HDL/LDL-cholesterol ratio were the lowest in group B. Left atrium diameter and right ventricle diameter were bigger in groups B and C compared to group A at the visit I and after 12 months of observation. Systolic intraventricular septum (IVS syst) thickness was the highest in group C at visit I. Diastolic left ventricle posterior wall thickness (LVPW) was the highest in group C during 12 months of observation., Conclusion: The increase in fat tissue mass may lead to increase in inflammatory process and cardiac muscle remodeling in AVS patients.

Background: The aortic valve has been the subject of many hemodynamic studies but, to our knowledge, posttranslational modification of human valve proteins has not yet been studied. Thus, the aim of this study was to determine whether any age-related changes in the protein composition of normal human aortic valves and their glycosylation pattern could be observed., Methods: Aortic valves harvested from male cadaveric donors free of cardiovascular diseases were divided into four age groups: I, mean age 21 years; II, 30 years; III, 41 years; IV, 51 years. Proteins were separated by SDS-PAGE and transferred to PVDF membranes. Identification of monosaccharide moieties or oligosaccharide units was performed with the use of eight lectins of narrow specificity: Galantus nivalis agglutinin, Sambucus nigra agglutinin, Maackia amurensis agglutinin, Datura stramonium agglutinin, Aleuria aurantia agglutinin, Arachis hypogeae agglutinin, Phaseolus vulgaris agglutinin, and Lycopersicon esculentum agglutinin., Results: Isolated proteins showed no age-related changes in SDS-PAGE protein profile, contrary to their glycosylation. Protein sialylation, number of tri/tetraantennary complex glycans, proteins having terminal galactose and polylactosaminyl units increased with age, whereas protein fucosylation showed the opposite relationship. Moreover, groups III and IV possessed a larger number of proteins bearing high-mannose and/or hybrid-type glycans, and the quantity of these structures seemed to change, in particular proteins, with the age of donors., Conclusions: Our results clearly demonstrate that glycosylation profile in human aortic proteins is associated with the age of the donor.

Unlabelled: The aim of the study is to estimate the operative risk of aortic valve replacement for severe aortic valve stenosis in patients with distinctly impaired left ventricular function (ejection fraction below 40%). From the population of 2512 pts, who underwent aortic valve replacement in the years 1990 to 1999 because of acquired malformation, a group of 108 pts (4.3%), fulfilling the above mentioned conditions was selected. Between them prevailed men, 92 (85.2%), and the average age was 53.4 +/- 14.5. All pts remained in the NYHA functional class III/IV. The average ejection fraction was estimated 28.2 +/- 14.3%. The pts demonstrated concentric left ventricular hypertrophy, severe aortic valve calcifications, the average valvular area was 0.91 cm2, and the pressure gradient over the valve was 71 +/- 44 mmHg. The pts were operated on by different surgeons but after the same protocol of extracorporeal circulation and cardioplegia administration. Low output syndrome occurred in ca 40% of pts, and cardiac failure was the main cause of death. The hospital mortality was 8.6%, and it was over two times higher then the whole population of pts, who underwent aortic valve replacement. All survivors (91.4%) demonstrated clinical improvement already during the early observation., Conclusions: Low ejection fraction is an important risk factor of surgery for aortic valve stenosis. However, the elevated operative mortality, comparable to other institutions, may be accepted taking for consideration, that surgery is the only way of treatment and improvement may be expected in about 90% of pts, including anatomical and hemodynamic parameters, as well as life longevity and comfort. In the extreme cases the HTX should be considered.

Background and Aim of the Study: The study aim was to assess histological and mineralogical properties of leaflets in human, antibiotic-preserved aortic homograft valves (recovered during surgical replacement) in order to identify factors accounting for pathological changes leading to accelerated graft dysfunction. A comparison was made with aortic valves prepared for grafting, with a view to assessing morphological and mineralogical characteristics as a potential preimplantation risk factor., Methods: Valve leaflets were examined with light and scanning electron microscopy. Mineralization was assessed histochemically, and also physicochemically by atomic absorption spectroscopy (AAS)., Results: All explanted homograft valve leaflets revealed prominent degenerative changes seen as decreased surface area, fibrosis, mineralization and focal thrombosis. Substantial loss of endothelium and fibroblasts, reduced collagen bundles crimping, inflammation (81%) and disappearance of layered structure (59%) was identified. The elastic elements were relatively stable, though a gradual age-dependent loss was observed in both groups. Accelerated mineralization was seen in all explanted homografts; inorganic deposits were composed mainly of hydroxyapatite. Two types of mineralization were identified: large limited nodular structures, and diffuse mineral deposits. Homografts with moderately elevated mineralization, well-preserved layered structure and sporadic infective changes proved to have the greatest durability. Homograft durability was also affected by the difference in host and donor age., Conclusion: Preimplantation factors affecting pathological changes determining homograft durability included morphological status of the graft itself and donor age; host-related factors included recipient age, endocarditis, native valve calcification, and host-donor matching (age difference between host and donor). A limited molecular mineralization may increase valvular durability, provided that no focal nodular calcifications exist that might adversely affect overall homograft integrity.

Background and Aim of the Study: The study aim was to evaluate the quality of life in patients after homograft or prosthetic aortic valve implantation. Evaluation was based on clinical and echocardiographic examinations, and on analysis of data from patient questionnaires., Methods: Patients undergoing either homograft (HV, n = 220) or prosthetic (PV, n = 220) aortic valve replacement were investigated. The patients groups were similar in age, sex, follow up period, risk factors and type of heart defect, and did not demonstrate any dysfunction of the replacement valve., Results: During both pre- and postoperative periods, no significant inter-group differences were identified with regard to the occurrence of retrosternal pain, dyspnea, palpitation, fear reaction and circulatory efficiency based on NYHA classification, and self-evaluation of physical activity assessed by patient questionnaires. The majority of patients in both groups noticed on increase in their quality of life and physical activity. The reduced sexual activity (50%) and fear reaction (30%) in both groups did not correlate with their improved sense of well-being. Up to 14.6% of PV patients did not accept the implanted valve, and 65 (29.5%) would have preferred an HV, despite the need for reoperation. Following surgery, 21% of HV patients resumed work, compared with only 7.7% of PV patients. The frequency of claims for disability pension after surgery did not correlate with the considerate clinical and subjective improvement., Conclusions: In patients receiving either homograft or prosthetic valves, the subjective evaluation of life quality is comparable with the clinical evaluation, though the homograft valve was better accepted than its prosthetic counterpart.

The material used for the studies consisted of allogenic aortic valves (AAV) collected from 14 individuals. The necessity of AAV replacement arose from growing circulation insufficiency and AAV dysfunction. The aim the study was the determination of the elemental composition and crystallographic structure of the inorganic deposits in AAV. Moreover, the results of the physicochemical investigations were correlated with clinical data (age of the patient, time between valve replacement surgeries, endomyocarditis, number of infections during last 12 months, arterial hypertension and disturbance of the lipid balance) and with echocardiographic examinations (cusp mineralization and perforation, vegetation, systolic and diastolic dimensions of the left ventricle, maximal and average gradient through allograft valve as well as range of the recoil wave to left ventricle). It was found that mineralization of the AAV cusps was a time-dependent process and took place predominantly at the surface of the cusp. The elemental composition and crystallographic data revealed that the inorganic deposits in AAV were composed of hydroxyapatite crystals. However, the presence of other calcium salts was also found. The development of the mineralization process in AAV does not correlate with endomyocarditis, arterial hypertension and the disturbance of the lipid balance. Probably, endomyocarditis and arterial hypertension induce the pathologic alternations of AAV independently from the mineralization process. The echocardiographic estimations of the pathomorphologic changes of the aortic valve cups are not always consistent with the results of the physicochemical studies.

Using mineralogic methods of investigation there were analyzed 8 mitral and 6 aortic valves, removed during surgical replacement, and 18 concretions which occluded coronary arteries, removed during surgical revascularization procedures. In all samples two kinds of mineralization were stated: 1. secret-observed as higher than normal content of elements in the tissue, and detected using chemical methods only, and 2. apparent-observed as grains and crystals, composed mainly of hydrated phosphates and hydroxyapatite, often with deposits of lipids and cholesterol.

Mineralization (calcification) of heart valves (mitral, aortic and aortic bioprosthesis) have been analyzed using; histology, x-ray diffraction, infrared spectroscopy, scanning microscopy, atomic absorption and electron microprobe. Obtained results showed the presence of two type of mineralization. First type is represented by grains composed of hydroxyapatite containing admixture of carbonates. This mineralization is seen macroscopically. Second type of mineralization is possible to determine only using chemical methods. It is represented by biological structures containing amount of Ca, P and other elements higher then normal heart valves. This second type of the mineralization conducts to the changes of physical features of the tissue. Both types of calcification develops because of the defects of atomic structure of biological components of heart valves (mainly collagen). These defects show the presence of free atomic bindings i.e. electric potential. Because of this, they are able to react with surrounding free joints, starting calcification. Defects of biological structures of heart valves are the results of infections, mechanical destruction of the valves etc. Calcification may be stopped on different stages of its development: or as secret calcification or may pass to the stage seen as apatite grains.