Even with advancements in surgical techniques, vascular complications remain life-threatening conditions and can lead to graft loss and sometimes recipient death. This paper examines the causes of vascular complications following a kidney transplant (KT), as well as international experience in the application of methods for early diagnosis, treatment and prevention of these complications.

Bronchial stenosis (BS) is a persistent, breathing-independent narrowing of the bronchial lumen, primarily brought on by scar and/or granulation tissue. BS occurring after lung transplantation tend to be recurrent, resulting in a higher frequency of hospitalizations compared to the group of patients without this complication. Minimally invasive endoscopic repair of the bronchial lumen is a generally recognized treatment for BS. This article demonstrates the experience of using a combined technique for restoring the lumen and preventing recurrent stenosis using thulium laser, balloon dilation, cryoablation, and stenting (hereinafter referred to as the combined technique).

This paper reviews the sources and generality of knowledge regarding the adverse effects of immunosuppressive therapy, which play an important role in the full functioning of a transplant. The article regarding the importance of the dynamic impact of immunosuppressant medications on transplant function and the need for reasonable regimen and dosage selection of individual drugs or their combination to minimize adverse effects.

Background. Liver transplantation (LT) in children with low body weight using the left lateral segment from a living donor is associated with large-for-size syndrome (LFSS). We present the first Russian clinical case of laparoscopic living-donor hepatectomy to acquire an S2 graft. Materials and methods. A six-month-old child who had biliary atresia-induced liver cirrhosis was prepared for transplantation. The child’s 20-year-old mother was the donor. The left lateral segment had a volume of 426 mL (graft-to-recipient weight ratio, GRWR, was 5.9%). Indocyanine green fluorescence-guided laparoscopic intracorporeal reduction up to the S2 segment was performed. Results. Donor operation time was 230 minutes, blood loss was 50 ml. The postoperative period was uneventful; the donor was discharged on day 9. The recipient had no surgical complications; a rejection episode was successfully managed. The child was discharged with a satisfactory graft function. Discussion. Fluorescenceguided laparoscopic living-donor hepatectomy to acquire an S2 graft is effective and safe. The presented technique may be an effective solution when performing monosegmental LT under the high-risk conditions of LFSS.

Objective: to study the prevalence of maladaptive left ventricular remodeling (MLVR) among kidney transplant (KT) candidates and the role of MLVR in the development of early graft dysfunction (EGD). Materials and methods. The study is based on a retrospective analysis of treatment outcomes in 650 patients who underwent a living related KT. Transthoracic echocardiogram revealed different types of left ventricular (LV) remodeling, whose prevalence was studied in the context of influence on the general population and specific «renal» risk factors. Two patient groups were also identified: Group I had EGD (n = 82) and Group II had primary graft function (PGF) (n = 79). These groups were comparable in terms of demographics, clinical data, and laboratory results (p > 0.1). The relative risk of developing EGD was calculated depending on whether maladaptive remodeling was present. Results. Concentric LV hypertrophy (cLVH) was detected in 341 (52.46%), eccentric (eLVH) in 174 (26.77%) patients. Concentric remodeling (CR) and normal LV geometry were detected in 86 (13.23%) and 49 (7.54%) patients, respectively. MLVR (cLVH + eLVH) was more common in men (p = 0.003). Compared to patients in the pre-dialysis stage, the risk of developing MLVR was 5.6 times higher for dialysis therapy durations up to 1 year, 8 times higher for durations 1 to 2 years, and 4.5 times higher for durations greater than 2 years (p < 0.05). The likelihood of developing MLVR was 8-fold higher in those with a functioning arteriovenous fistula (p < 0.001). As diuresis decreased, the odds of developing MLVR increased 4 to 15.8 times (p < 0.001). Depending on the severity of their anemia, patients with anemia had 2.7–13.8 times the chances of developing MLVR compared to those without anemia (p < 0.05). According to comparative analysis, the EGD group had a high prevalence of MLVR (p = 0.01). MLVR raised the risk of developing EGD in the post-transplant period by 8.5 times for cLVH (p = 0.049) and 14.5 times for eLVH (p = 0.011). Conclusion. The presence of MLVR in a KT candidate indicates the severity of cardiovascular disease brought on by progression of chronic kidney disease, and can also be regarded as one of the risk factors for EGD.

Kaposi’s sarcoma (KS) is a malignant tumor caused by human herpesvirus 8. Due to etiological and pathogenetic factors, this type of tumor is common among patients with immunodeficiency of various genesis. Solid organ recipients are at a high risk of developing malignant tumors in various locations due to the peculiarities of subsequent drug immunosuppressive therapy. Because KS is so common in this patient cohort, methods for early detection, efficient treatment, and prevention of the neoplastic process must be developed. This paper presents a clinical case of a successful surgical treatment of KS of the aryepiglottic fold using an endoscopic electrosurgical station with an argon complex.

Objective: organ transplantation is a highly effective and often the only possible definitive treatment for terminal diseases, significantly improving patient survival and quality of life. However, recipients have a higher risk of developing cardiovascular and oncological diseases, and are susceptible to decompensation of pre-existing diseases. Prevention and treatment of these conditions are becoming critical tasks in transplantology, requiring multidisciplinary collaboration. Materials and methods. This article presents a clinical case of the treatment of a patient with stage 5 chronic kidney disease, concomitant cardiologic pathologies and subsequently diagnosed hepatocellular cancer on the background of hepatitis C-related liver cirrhosis. Competent interaction and bridge therapy yielded successful consecutive kidney and liver transplantation with satisfactory outcomes. Conclusion. Our treatment experience has shown the effectiveness and necessity of a multidisciplinary approach, early diagnosis, therapy modification during transplantation and further treatment of patients with end-stage multiple organ dysfunction.

The structure of allograft dysfunction is heterogeneous, and the peculiarities of its course depend on the underlying pathological process as well as other factors that influence how quickly it progresses. The most significant of these factors are the prevalence of interstitial fibrosis and tubular atrophy. Objective: to evaluate the factors influencing the rate of nephropathy progression depending on the nature of dysfunction. Materials and methods. The study included 189 kidney transplant recipients with morphologically verified renal graft dysfunction. Patients were divided into five categories based on their morphological pictures: Group 1, acute tubular necrosis (ATN) (n = 20); Group 2, cellular rejection (CR) (n = 50); Group 3, antibody-mediated rejection (AMR) (n = 61); Group 4, interstitial fibrosis and tubular atrophy (IFTA) (n = 41); Group 5, recurrent or de novo glomerulonephritis (GN) (n = 17). Results. Even though graft function tended to improve with treatment, The CR and AMR groups had the lowest long-term graft survival rates at 12 months, amounting to 64% and 54%, respectively, while the IFTA and GN groups had the highest, 79% and 86%, respectively. ATN patients (94%) showed the best 1-year survival. In the multivariate analysis performed in the Cox regression model, only two factors – creatinine level at the time of biopsy and IFTA prevalence – were found to be independent predictors of prognosis, regardless of the underlying mechanism of injury. A prognostic model that incorporates both characteristics demonstrated significantly higher prognostic accuracy. A combination of creatinine level ≥200 μmol/L and an interstitial fibrosis prevalence ≥20% of the parenchyma area showed the strongest correlation with prognosis. This model had a 91% sensitivity and a 28% specificity (p < 0.01 95% CI: 0.74–0.89). Conclusion. When assessing the risk of graft loss, it is necessary to consider the entire set of potential prognostic factors, such as the nature of the underlying disease, severity of graft dysfunction and prevalence of background interstitial fibrosis. 

Heart transplant (HT) is an effective treatment option for patients with end-stage chronic heart failure, as it can restore their ability to work, facilitate physical and social rehabilitation, and significantly improve their long-term survival. Objective: to evaluate the psychological and physical well-being of HT recipients using a comparative analysis of the TxEQ, PTGI, and SF‑36 questionnaires and the impact of the obtained results on the frequency of visits to health care facilities. Materials and methods. The findings of the study were derived by analyzing the data of recipients by random randomization, who were observed on an outpatient basis at Shumakov National Medical Research Center of Transplantology and Artificial Organs. The TxEQ, SF‑36, and PTGI questionnaires were used to assess recipients’ psychological and physical well-being. For comparative analysis, HT recipients were divided into three equal groups based on the total score obtained when assessing each factor in the TxEQ questionnaire. Results. A comparative evaluation of factors from the TxEQ questionnaire and scores from the SF‑36 questionnaire revealed that recipients who scored poorly on a particular factor had better mental health (p = 0.02). Recipients who are more eager to inform others about their surgery show better vitality (p = 0.019). Analysis of the «Medication adherence» factor found that there was a significantly high compliance of recipients to taking their medications (p = 0.01). Subsequent data analysis showed that the total PTGI score strongly correlated with the factors «Responsibility», «New life perspectives», «Disclosure» and «Medication adherence» (p < 0.005). While analyzing factors from the TxEQ questionnaire and the frequency of recipients’ outpatient visits to health care facilities, it was revealed that recipients who were more worried about their surgery and those who exhibited high medication adherence during the follow-up year visited health care facilities more often (p < 0.005). Conclusion. Regularly assessing the quality of life in HT recipients is a key factor of outpatient followup, which allows to significantly improve physical and psychological well-being, and ultimately preventing the risk of negative health complications.

Extracorporeal membrane oxygenation (ECMO) is a vital tool in the treatment of patients with severe cardiovascular failure during heart surgery. The femoral artery is the most common access for veno-arterial ECMO in adults. Where there are contraindications to traditional cannulation techniques, the subclavian artery is an alternative access site, despite its many peculiarities. This paper presents a clinical case where peripheral ECMO connection with cannulation into the subclavian artery using a cryopreserved homovital abdominal aortic homograft was performed in a patient.

Bioengineered pancreatic constructs based on scaffolds made from decellularized tissues and pancreatic islets (PIs) may be used to extend the functional activity of transplanted PIs in patients with type I diabetes. Objective: to investigate in vitro the effect of decellularized porcine liver scaffold (DPLS) on the viability and insulin-producing capacity of isolated human PIs. Materials and methods. The resulting DPLS was subjected to histological examination, DNA quantification, and cytotoxic effect testing. The PIs were isolated from human pancreas fragments using the collagenase technique. Under standard conditions, PIs were cultured in three different environments: monoculture (control group), with DPLS present (experimental group 1) or with decellularized human pancreas scaffold (DHPS) present (experimental group 2). Vital fluorescent dyes were used to evaluate the viability of PIs. Basal and glucose-loaded insulin concentrations were determined by enzyme immunoassay. Results. The basic composition and structure of the extracellular matrix of liver tissue in DPLS samples were preserved thanks to the selected decellularization procedure. The samples had no cytotoxic effect, and the residual amount of DNA in the scaffold did not exceed 1.0%. PIs from the experimental groups showed no significant signs of degradation and fragmentation during the 10-day incubation period compared to PIs from the control group. On day 10, the viability of PIs from experimental group 1 was 64%, that of experimental group 2 was 72%, and that of the control group was less than 20%. After the first day of culturing, insulin concentration were 29.0% higher in experimental group 1 and 39.1% higher in experimental group 2 compared to the control group. On day 10 of the experiment, insulin levels in experimental groups 1 and 2 differed by 124.8% and 150.9%, respectively, from the control group. Under a glucose load, the insulin level in experimental group 1 was 1.7 times higher than in the control group, whereas that of experimental group 2 was 2.2 times higher. Conclusion. The resulting DPLS has a positive effect on the viability and insulin-producing capacity of PIs. When creating a bioengineered construct of PIs, DPLS can be used as a component obtained in sufficient quantity from an available source.

Objective: to develop and investigate a tissue-specific matrix obtained using a modified chemical porcine liver decellularization regime in order to effectively increase preservation of extracellular matrix (ECM) structure, reduce decellularization time and improve purification of the ECM from cellular elements. Materials and methods. Original porcine liver was minced to obtain tissue fragments. Five decellularization regimes were used, with the concentrations and timing of surfactant treatments varied: 0.1% sodium dodecyl sulfate (SDS) and 0.1% or 1% Triton X-100, without and in combination with phosphate-buffered saline (PBS). The glycosaminoglycan (GAG) content of the resulting fragments was determined by lysing the samples for 12 hours in papain solution at +65 °C and then incubating them in 1,9-dimethylmethylene blue. DNA quantification was carried out using DNeasy Blood&Tissue Kit and Quant-iT PicoGreen dye. The morphology of the samples was studied using histological staining techniques. Cytotoxicity of the samples in vitro was evaluated on an NIH/3T3 mouse fibroblast culture by direct contact. Results. Treatment with 0.1% SDS for 2.5 hours with additional treatment with 1% Triton X-100 containing PBS for 21.5 hours (regime 4) increased GAG content to 11.66 ± 0.61 μg/mg compared to 0.68 ± 0.06 μg/mg (regime 5). The DNA content of samples obtained in regime 4 decreased from 99.75 ± 3.93 ng/mg to 14.93 ± 4.91 ng/mg after additional treatment with type I DNase, indicating that cellular components were effectively removed. This matrix showed no cytotoxicity. Conclusion. By optimizing the chemical decellularization regime for porcine liver, we were able to improve preservation of ECM structures, shorten decellularization time and effectively reduce the content of cellular elements. The modified decellularization protocol allowed to obtain a non-cytotoxic tissue-specific matrix with a low potential immunogenicity and a more preserved ECM structure and higher GAG content.

Organ transplantation continues to be the gold standard for saving the lives of patients with end-stage organ diseases. Its goal is to help recipients live longer and better lives. However, despite advancements, organ transplantation still faces serious challenges, such as organ shortage and the effects of chronic immunosuppression. In this regard, there is ongoing vigorous search for therapeutic strategies that can improve the efficacy of allogeneic organ transplantation. Mesenchymal stems cells (MSCs) can significantly enhance and accelerate regenerative processes in damaged organs, can angiogenesis angiogenesis and inhibit cell apoptosis, inflammation and fibrosis formation, and have immunomodulatory properties. Researchers and physicians are interested in MSCs because of a set of unique properties that could be useful in solid organ transplantation. This review critically analyzes and summarizes the actual clinical data related to the study of the therapeutic effects of MSCs in organ transplantation. Electronic databases Medline/PubMed (www/ncbi.nlm.nih.gov/pubmed) and eLIBRARY/Russian Science Citation Index (https://www.elibrary.ru) were searched for relevant literature. Inclusion criteria were clinical use of MSCs to improve the condition of kidney, liver, lung, heart and pancreas recipients, and to enhance graft quality. Exclusion criteria for articles included the use of MSCs for the treatment of non-transplant patients, as well as articles detailing the effects of MSCs products (exosomes, vesicles and conditioned media) and research studies conducted in vitro and in vivo (without patient participation), conference proceedings, reviews and preprints of articles. Thirty-one original articles in English and Russian languages were selected for literature review. The prospects of MSCs in transplantology are also covered in the paper.

Objective: to study the composition and topology of the extracellular matrix (ECM) of bovine pericardium and to identify the best tissue areas suitable for the fabrication of bioprosthetic heart valves (BHVs). Materials and methods. The pericardium samples of healthy sexually mature bulls were studied; the native pericardium was divided into three experimental groups: core tissue (BP-CT group), heart base (BP-HB) and connective ligament base (BP-CL). Scanning electron microscopy was used to examine the structure of the pericardial surfaces (p. serosum and p. fibrosum), while differential histochemical analysis was used to study the topology of various pericardial regions, with identification and quantification of the main constituents of the extracellular matrix (ECM) (collagen, elastin, lipids, and glycosaminoglycans). Quantification was performed by bioimaging and digital analysis of histological images using the ImageJ software. Results. The BP-CT group had the lowest cellular density and, consequently, DNA content (369.75 ± 23.12 ng/mg), in addition to having the most homogeneous, predominantly collagenous (95.6 ± 2.9%) matrix composition with minimal lipid (2.6 ± 1.5%), glycosaminoglycan (0.68 ± 0.7%) and elastin (3 ± 2.4%) content. The BP-CL group had the highest levels of elastin and glycosaminoglycans (27.8 ± 3% and 17.5 ± 0.6%, respectively), while the BP-HB group had the highest lipid content (21.2 ± 2.7%.). On the p. serosum side, the ECM composition was noticeably homogeneous, while elastin fibers, glycosaminoglycans, and lipid clusters were predominantly found on the p. fibrisum side, indicating the natural polarity of the material, which should be considered when fabricating biomaterials. Conclusion. The findings in this study revealed that bovine pericardial topology varied depending on the tissue area. Only the main pericardial tissue can be used to create BHVs, as evidenced by the comparative homogeneity of ECM composition and relatively low cellular density. The high content of elastin, glycosaminoglycans and lipids in specific pericardial tissue areas (the BP-HB and BP-CL groups) suggests that either this layer needs to be removed more thoroughly during implant fabrication (e.g., by selective purification techniques) or these pericardial tissue areas should be used where heterogeneity of the composition is desired (e.g., in maxillofacial and orthopedic surgery).

Minimally invasive living-donor hepatectomy is a relatively new surgical technique that can improve donor safety and expedite donor rehabilitation. Following an early stage of research where donor safety was not adequately established, the minimally invasive approach nowadays yields better outcomes when carried out by experienced surgeons. Important factors include donor selection criteria, hospital equipment, and surgeon’s learning curve. This review describes the current status of laparoscopic and robotic living-donor hepatectomy, along with the challenges facing the advancement of these surgical techniques.

Objective: to assess the prevalence of primary arteriovenous fistula (AVF) failure in patients commencing chronic hemodialysis, to evaluate the relationship between primary failure and long-term outcomes, and to identify risk factors for its development. Materials and methods. This retrospective cohort study reports the outcomes of 1595 adult patients starting chronic hemodialysis treatment for the first time. Results. Primary failure was noted in 369 patients (23.1%), whereas in 1,226 patients (76.9%), the AVF matured normally and was accessible to puncture without additional interventions. Follow-up by a nephrologist, preoperative evaluation by a surgeon, and ultrasound were linked to a lower risk of primary failure: RR = 0.624 [95% CI 0.523; 0.746], p < 0.001; 0.648 [0.469; 0.894], p = 0.005; and 0.606 [0.471; 0.78], p < 0.001 (when ultrasound was performed by or in the presence of a surgeon 0.372 [0.24; 0.577], p < 0.001), respectively. The risk of primary failure increased if AVF was created in two weeks and one week before, and during the first and second weeks after hemodialysis initiation. In single-factor analysis, primary failure was linked to a higher risk of all-cause mortality (HR = 1.54 [1.20; 1.97], p < 0.001), but not after adjustment for age and comorbidity (HR = 1.11 [0.85; 1.44], p = 0.761). Primary failure was associated with poorer secondary patency (HR = 1.79 [1.28; 2.51] p < 0.001) and increased need for reconstructive interventions (IRR = 2.199 [1.985; 2.434], p < 0.001). Conclusion. Risk reduction factors for primary failure include follow-up by a nephrologist, preliminary examination by a surgeon, supplemented by ultrasound scan. Primary failure is not linked to decreased patient survival (after adjustment for comorbid background and age), but to decreased secondary patency of vascular access.

Objective: to compare the remodeling features of polyurethane (PU) and bovine pericardium (BP) patches that have been implanted in a sheep carotid artery for 6 months. Materials and methods. Synthetic matrices were fabricated from a 12% PU solution in chloroform by electrospinning on a Nanon-01A machine (MECC, Japan). Biological matrices made from commercially produced PU (Kem-Periplas Neo, CJSC Neocor, Russia) were used for comparison. The matrices were implanted as vascular patches into sheep carotid arteries (n = 3). Implantation period was 6 months. Via ultrasound scan, the patency of arteries bearing the implanted vascular prostheses was evaluated. After removal, the matrix samples were studied by histological examination, scanning electron microscopy and confocal microscopy. Prior to this, they had been stained with specific fluorescently labeled antibodies. The GraphPad Prism 8 application was used to process statistical data. Results. The sheep carotid artery wall was completely patent, with no aneurysmal dilatations, significant stenoses, and hematomas six months after the PU and BP matrices were implanted. The PU matrix was distinguished by a less pronounced connective-tissue capsule and no neointima hyperplasia; the thickness of the remodeled PU wall was 731.2 (711.5; 751.3) μm. At the same time, there was BP neointimal hyperplasia with a thickness of 627 (538; 817) μm and a remodeled wall thickness of 1723 (1693; 1772) μm. In comparison to BP, the PU matrix exhibited greater endothelialization and structural integrity. Conclusion. An in vivo study on sheep demonstrated the potential of PU matrix, a novel and effective material for vascular reconstruction, to maintain harmonious remodeling, bioinertness and structural integrity when in contact with blood. Due to its excellent elastic qualities and durability, PU is interesting both as a monocomponent and as a component of a composite material that can be used to create products for the needs of cardiovascular surgery.

Bioprosthetic heart valves (BHVs) rarely last longer than 20 years due to the development of degenerative changes in their leaflets. We present a detailed pathomorphological description of KemCor, an epoxy-treated BHV that was removed from the mitral position 25 years after implantation. Literature review shows that this is the longest recorded lifespan of an epoxy-treated implant.

Selecting a permeation enhancer complex (PEC) for inclusion in a matrix-type transdermal patch (TP) is a primary task in creating a new dosage form with percutaneous administration. Objective: to develop a biologically safe PEC capable of regulating percutaneous diffusion of low-molecular-weight drugs from the polyacrylate matrix of a TP and without causing adverse skin reactions. Materials and methods. The PEC contained apricot kernel oil, dioctyl sodium sulfosuccinate, dihydroquercetin and alpha-tocopherol acetate – substances that have a good impact on the functional properties of polymer-based TPs. Low-molecular alcohol-soluble drugs (chlorpropamide, caffeine and sodium benzoate and lidocaine hydrochloride) used to treat diseases of various etiologies were used as active ingredients. In vitro studies of percutaneous drug delivery were carried out on male Chinchilla rabbits in Franz glass diffusion cells using a drug diffusion analyzer. Using spectrophotometry and high-performance liquid chromatography, concentrations of drugs in aqueous solutions and in the blood plasma of the laboratory animals were measured. The irritant effect of the lidocaine-loaded transdermal polymeric matrix was tested on sexually mature young male New Zealand White rabbits. Results. When PEC was introduced into the polymer matrix film, percutaneous diffusion of the drugs increased significantly from 2.1 ± 0.4 to 9.2 ± 1.4 mg over 24 hours of experiment for the chlorpropamide-loaded TP and from 9.2 ± 1.2 to 35.2 ± 7.5 mg for the caffeine-loaded TP. Additionally, there was a 1.7- and 2.9-fold decrease and a 2.3- and 2.7-fold increase in the time to reach a constant drug concentration in blood for the chlorpropamide- and caffeine-containing TPs, respectively. Using the lidocaine- and chlorpropamide-loaded TPs, it was shown that the presence of PEC in the polymer matrix film causes no skin irritation and that the shelf life of the transdermal form increases from 1 to 3 years. Conclusion. Introduction of the proposed PEC into the polymeric matrixes of TPs enhanced percutaneous diffusion of the drugs, reduced skin irritation from the TP components, and increased the shelf life of the finished dosage forms.

Late complications affecting the cardiovascular system depend on the extent of the capture of cardiac structures in the radiation field and the cumulative dose of exposure. They are characterized by polymorphism in clinical manifestations. Objective: to identify the predictors influencing in-hospital mortality (IHM) in order to optimize the treatment of patients with radiation-induced heart disease. Materials and methods. This is a single-patient cohort study that was retrospective from 2004 to 2018 and prospective from 2018. Death after 30 days following heart valve surgery (HVS) under artificial circulation was taken as the end point of the study. The study included 86 patients (mean age 59 ± 13 years, 81.4% female) who underwent HVS. They were split into 2 groups (extensive, tangential) depending on the cause of cancer. Results. In the postoperative period, the group with extensive irradiation had statistically significant differences in the need for prolonged ventilation, OR 5.17 (CI 95% 1.7–15.7), more frequent exudative pleurisy OR 3.4 (CI 95% 1.1–10.8), and acute renal failure OR 1.2 (CI 95% 1.05–1.37). Regardless of postoperative complications, the length of hospital stay did not differ statistically across the groups, with a median of 10.5 (CI 7.25:16.75) vs. 11 (CI 9:15.25) days, respectively. Overall IHM was 14 (16.27%) patients. Multiple organ failure (MOF) was the cause of death in 9 cases. Multivariate analysis revealed that extensive irradiation for lymphogranulomatosis increased IHM risk by 5.099 times, and an increase in the EuroSCORE II score by every «1» increased IHM risk by 1.19 times. Conclusion. Patients with post-radiation damage to heart valves and coronary arteries with a history of tangential irradiation can be successfully operated on. Extensive irradiation in anamnesis is associated with a high risk of heart failure and MOF in the early postoperative period.