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Background Whereas the risk factors for structural valve degeneration (SVD) of glutaraldehyde-treated bioprosthetic heart valves (BHVs) are well studied, those responsible for the failure of BHVs fixed with alternative next-generation chemicals remain largely unknown. This study aimed to investigate the reasons behind the development of SVD in ethylene glycol diglycidyl ether-treated BHVs. Methods and Results Ten ethylene glycol diglycidyl ether-treated BHVs excised because of SVD, and 5 calcified aortic valves (AVs) replaced with BHVs because of calcific AV disease were collected and their proteomic profile was deciphered. Then, BHVs and AVs were interrogated for immune cell infiltration, microbial contamination, distribution of matrix-degrading enzymes and their tissue inhibitors, lipid deposition, and calcification. In contrast with dysfunctional AVs, failing BHVs suffered from complement-driven neutrophil invasion, excessive proteolysis, unwanted coagulation, and lipid deposition. Neutrophil infiltration was triggered by an asymptomatic bacterial colonization of the prosthetic tissue. Neutrophil elastase, myeloblastin/proteinase 3, cathepsin G, and matrix metalloproteinases (MMPs; neutrophil-derived MMP-8 and plasma-derived MMP-9), were significantly overexpressed, while tissue inhibitors of metalloproteinases 1/2 were downregulated in the BHVs as compared with AVs, together indicative of unbalanced proteolysis in the failing BHVs. As opposed to other proteases, MMP-9 was mostly expressed in the disorganized prosthetic extracellular matrix, suggesting plasma-derived proteases as the primary culprit of SVD in ethylene glycol diglycidyl ether-treated BHVs. Hence, hemodynamic stress and progressive accumulation of proteases led to the extracellular matrix degeneration and dystrophic calcification, ultimately resulting in SVD. Conclusions Neutrophil- and plasma-derived proteases are responsible for the loss of BHV mechanical competence and need to be thwarted to prevent SVD.

Objective: To compare the neointima structure in conduits for coronary bypass grafting, bioprosthetic heart valves, tissue-engineered vascular grafts, and metal stents., Material and Methods: The objects of the study were the fragments of the human internal thoracic artery, experimental biodegradable vascular prostheses, leaflets of xenopericardial bioprostheses of heart valves, and fragments of stented vessels. Tissue samples were fixed in formalin and post-fixed in osmium tetroxide. After dehydration and epoxy resin embedding, the samples were ground and polished. Samples were counterstained with uranyl acetate and lead citrate and visualized by means of backscattered scanning electron microscopy., Results: Neointimal pattern in all samples was similar. Neointima was comprised of endothelial cells, smooth muscle cells, fibroblasts, and the extracellular matrix. Endothelial cells showed significant diversity both between different elements of the circulatory system and within the same tissue, having either elongated or polygonal shape. Adhesion of leukocytes testified to the endothelial cell activation. In the absence of inflammation in the superficial layer of the neointima, the arrangement of smooth muscle cells and extracellular matrix fibers was parallel to the endothelium. Clusters of foam cells were frequently detected around the neointimal layers with solid inclusions (metal stents or calcium deposits). Thickening of the neointima was accompanied by the presence of capillaries and capillary-like structures., Conclusion: Neointima formation is a typical response to the damage inflicted to the elements of the circulatory system. Neointima underwent a constant remodeling characterized by an altered cellular composition, macrophage invasion, neovascularization, and calcification.

Objective: To describe geometric models of carotid artery bifurcation and computer modeling of carotid endarterectomy (CEA) with patches of various configurations., Material and Methods: The method was demonstrated on a reconstructed model of intact vessel based on preoperative CT of the affected vessel in a certain patient. Blood flow is modeled by computational fluid dynamics using Doppler ultrasound data. Risk factors were assessed considering hemodynamic parameters of vascular wall associated with WSS., Results: We studied hemodynamic results of 10 virtual CEA with patches of various shapes on the example of a reconstructed intact artery in a particular patient. Patch implantation is aimed at prevention of carotid artery narrowing since simple suture without a patch can reduce circumference of the artery by 4-5 mm. This result adversely affects blood flow. On the other hand, too wide a patch creates aneurysm-like deformation of internal carotid artery bulb. It is not optimal due to a large recirculation zone. It was found that patch width approximately equal to 3 mm ensures an optimal hemodynamic result. Deviations from this median value, both upward and downward, impair hemodynamics while the absence of a patch results the worst result., Conclusion: The proposed computer modeling technique is able to provide a personalized patch selection for CEA with low risk of restenosis in long-term follow-up period.

The expression level of IL1B, IL6, IL8, IL10, IL12A, IL12B, IL18, IL23, IL33, CCL2, and IL1RL1 has been investigated using biopsies of native mitral, aortic, and tricuspid valves obtained during surgical correction of acquired defect from 25 patients with infectious endocarditis. Biopsies of native mitral and aortic valve cusps from 12 patients who underwent surgical correction of acquired heart disease of non-infectious etiology were used as control. We used quantitative PCR with fluorescent dye SYBR Green for determination of the cytokine gene expression level. This study revealed that genes could be subdivided into three groups: (i) genes with increased expression (IL1B, IL6, and IL8); (ii) genes with reduced expression (IL33 and IL1RL1); (iii) genes with unchanged expression (IL12A, IL18, IL23, and CCL2). The IL8 gene expression was characterized by the most pronounced increase (9.83 times versus control), while the IL1RL1 gene demonstrated the most pronounced decrease in its expression (4.17 times). Expression of IL10 and IL12B genes was negligible in all samples.

Sutureless implantation of the mitral valve bioprosthesis using the valve-in-valve method was performed on a large animal (sheep). According to the results of a two-stage implantation (primary implantation of a xenopericardial 26-mm framed bioprosthesis and reimplantation of the developed 23-mm bioprosthesis), minor changes in quantitative indicators were revealed: an increase in the transprosthetic gradient by 1.3 mm Hg and a decrease in the area of the mitral orifice by 21.6%. Considerable reduction in the intervention time by 18 min was achieved (by 40% in comparison with the primary prosthesis). The absence of adverse events in the animal and complications in the post-operative period, as well as physiological hemodynamic indicators indicate the safety of the developed medical device.

Experimental comparative morphological investigation of hemomicrocirculation bed (HMCB) of the small and large bowel wall was performed in dynamics of an acute serous peritonitis. Spreaded aseptic peritonitis was simulated using injection of 5 ml of gamma-caraginen (Sigma, USA) in 1 ml of isotonic solution of sodium chloride. On the early stage of peritonitis (in 12 h from beginning of the experiment) in mucosa of small bowel nonsignificant venuls dilatation and the capillary lumen reduction were observed. In 1 day (reactive stage of peritonitis) in mucosa the quantity of capillars have had reduced significantly, comparing with such observed previously. On the 2-nd day (toxic stage of peritonitis) some capillary dilatation in intestinal villi and crypts coexistant with the blood rheology disorders in a form of stasis, change in permeability of the vessels walls, predominantly of the venous, was noted. On the 3-d day (late stage) the arteriol's spasm have had reduced, capillary paralytic dilatation was revealed. The staged course of experimental peritonitis with the HMCB changes, characteristic for every stage, was confirmed, basing on analysis of the investigation result.

Background and Aim of the Study: Restrictive annuloplasty remains the most widespread technique for the correction of chronic ischemic mitral regurgitation (IMR). However, this technique only partially corrects the underlying pathophysiology and does not address the restricted leaflet motions during systole that result from progressive left ventricular (LV) remodeling., Methods: A novel experimental model of IMR was developed using an isolated pig heart placed on a hydrodynamic test-stand. A T-shaped LV patch was sutured onto the posterior wall of the left ventricle to simulate LV dilatation secondary to post-MI remodeling., Results: Using this model, a novel technique of subvalvular mitral valvuloplasty was described that reduces the distance between the posterior mitral annulus and the papillary muscle base and appears to be effective in eliminating IMR. Pledgetted 2-0 non-absorbable sutures were placed at the base of one papillary muscle, then through the other papillary muscle and then brought to the posterior mitral annulus. The same sequence was repeated in the other direction. A specific formula was then used to calculate the length of the subvalvular support prior to suture tying., Conclusion: Subvalvular support of the mitral apparatus in chronic IMR can be achieved using this simple method, which appears to be effective in eliminating IMR. Further data relating to the use of this technique in the clinical setting as an adjunct to mitral annuloplasty are forthcoming.

Individual values of clinic-laboratory indices were analyzed in 125 patients, suffering severe forms of an acute pancreatitis (AP). In the early postoperative period there were analyzed 65 indices: clinical analysis of the blood, 24 hematological indices, biochemical analysis of the blood, coagulogram, estimates according to the ASSES, APACHE II, SAPS, SAPS II, SAPS III scales. There was established, that in 83.1% of patients in severe forms of an AP the ratio or the values difference of clinic-laboratory indices in dynamics of postoperative period are depicted according to the "Golden section" rule with deviation no more than 10-15%. In the patients, suffering sterile pancreonecrosis, in comparison with those, suffering infected pancreonecrosis and in the patients with infected pancreonecrosis without retroperitoneal space cellular tissue affection in comparison with patients, suffering infected pancreonecrosis and the retroperitoneal space cellular tissue affection there were more signs, the values ratio or difference of which have deviated from the "Golden section" rule no more than by 5%. While estimating the patients state severity in those, suffering severe forms of AP, using special scales, most precisely the coincidence with a "Golden section" rule was noted, according to scales ASSES and SAPS III. Prognostically unfavorable was a progressive increase of the points sum according to ASSES scale in dynamics of postoperative period.

We studied inotropic reaction of isolated myocardium of patients with heart failure induced by ischemic and rheumatic cardiac involvement after periods of rest at the background of amiodarone. The studies were carried out on muscular trabeculi separated from right atrial auricle during surgery. It was shown that inotropic reaction of insufficient myocardium could be of 2 types. In type I inotropic reaction first contraction after period of rest either exceeded basal contractions or remained at their level. Type 2 was characterized by significant lowering of amplitude of contractions relative to regular ones. Exposure of the myocardium to amiodarone (1 micro/L) led to significant potentiation of trabeculi contraction after periods of rest of muscles with type I reaction and did not affect response of muscles with type II reaction. These results allow to conclude that the state of calcium transporting systems of sarcoplasmic reticulum (SR) is different in ischemic and rheumatic heart failure and that realization of therapeutic effect of amiodarone depends on functional state of SR.

Aim: To assess effect of calcium antagonists amlodipine and verapamil on the risk of development of atrial fibrillation after coronary artery bypass surgery., Material: Of 74 patients subjected to mammary artery and venous coronary bypass grafting with the use of cardiopulmonary bypass 19 received amlodipine and 21 - verapamil., Results and Conclusion: Attacks of atrial fibrillation during 24 hour ECG monitoring were registered in 22.9% of patients mostly on days 2 and 3 after surgery. In verapamil treated patients atrial fibrillation occurred 1.5-2 times more often than in amlodipine treated patients or in patients receiving no calcium antagonists. This could possibly be explained by pronounced slowing of atrio-ventricular conduction by verapamil at the background of postoperative general "irritation" of the atrial myocardium.

Intraoperative correction of preload in patients with acquired valvular disease (AVD) complicated by right-ventricular failure and severe pulmonary hypertension necessitates search for pathogenetically based algorithms of anesthesiological strategy. The objective of this study was to develop a strategy of assessing and treating the preload at the stage of induction anesthesia in patients with right-ventricular failure. During surgery central hemodynamic parameters and their response to a short head-down-tilt (15-20 degrees) were evaluated in patients (n = 42) with cardiac index (CI) less than 2 l/min/m2 after induction anesthesia. The patients were divided into 2 groups with different severity of preoperative status. Group 1 (main) included 24 patients with stages II-III cardiac failure (according to N. Strazhesko and B. Vasilenko) and group 2 (control) consisted of 18 patients with stage IIA cardiac failure. Progressing preoperative cardiac failure resulted in decrease of cardiac index and failure of compensatory hemodynamic mechanisms in AVD patients. The level of right-ventricular preload, pulmonary resistance, and stroke index were lower in group 1 than in the controls; however, 8% of group 1 patients responded positively to increased preload. In the control group 50% responded favorably to head-down-tilt. Hence, comprehensive assessment of cardiac index, central hemodynamic parameters and their response to head-down tilt help individually choose the anesthesiological strategy.

The phenomenon of chirality is described in terms of symmetry and via symmetry operators.

The early and long-term results of truncus brachiocephalicus prosthetics in its atherosclerotic occlusions are analysed. EEG mapping, radioisotopic examination of cerebral circulation before and after surgery, clinical examination were performed for evaluation of effectiveness and safety of surgery. The rate of mortality was 6.6%. The technical recommendations are provided. All the patients, who were discharged after surgery, are alive for 2.6 +/- 0.3 years. No cases of recurrence of cerebral circulation disorders were observed. In 100% cases the grafts were patent.

The object of the work was evaluation of the method of vasotonometry (VTM) in the episcleral arteries in recognizing stenoses of the extracranial part of the internal carotid artery (ICA). The examination was conducted by means of a specially designed vasotonometer in patients suffering from ischemic type cerebral circulatory disorders. The authors examined 98 patients and 20 healthy volunteers. The parameters of the diagnostic sensitivity of the method in various degrees and forms of the stenotic lesions of the ICA were determined. The correct diagnosis of a hemodynamically significant ICA stenosis was established in 85% of patients. The results of the examination were confirmed by angiography and operation.

Using the preparation method, roentgenoangiography by means of contrast lead mass and polychromic injection of the coronary vessels, vascularization of the interventricular septum (IVS) and the septal papillary muscles (SPM) has been studied on 49 preparations of human hearts (age 19-89) The data are presented on distribution pattern of the IVS and SPM of the coronary arteries branches at various types of the cardiac blood supply. Angioarchitectonics of the IVS is described along its whole length. Topographic peculiarities of the SPM blood supply on dependence of their position on the IVS are noted.

Based on the maternal pertaining to 193 patients with cancer of the esophagus and proximal gastric portion, 22 patients with non-tumor diseases of the stomach and esophagus, 19 donors (aged 18-25 years) and 10 practically healthy subjects aged 34-67 years, it was found that tumor invasion of the stomach body and the presence of such aggravating factors as grade IV dysphagia, inflammatory complications etc. are associated with a significantly increased intensity of serum chemiluminescence. Anesthesia and other factors as a concomitant of surgery reduce considerably the level of blood serum chemiluminescence during the operation, whereas an intensive postoperative therapy retains its initial level. The development of complications during the operation and after it is accompanied with 1.5--2 times or more increased luminescence. Radical surgical and combined treatment would condition the normalization of the luminescence. Radiation treatment first increases and then decreases the luminescence down to normal values.

The report deals with the results of examination of 48 healthy donors and 261 patients suffering from malignant tumors of cardia and esophagus, 84 patients after radical surgery included. Spontaneous chemoluminescence (CL) of blood serum was shown to depend on the general condition of the patient and tumor involvement before treatment: there is a direct correlation between these factors and luminescence intensity. Therefore, CL may be used as a laboratory test providing necessary information for developing treatment modality for each individual case. Within 0.5-60 months after radical treatment, the rise in the intensity of blood serum CL (60-100% and more) was registered in cases of pyo-inflammatory complications (peritonitis, mediastinitis, pleural empyema, etc.) and recurrence and metastatic spreading. A rise in CL intensity by more than 50% and a steady tendency to further increase may be interpreted as a pointer to recurrence or metastasis development.