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Dialysis-dependent (DD) patients undergoing coronary artery bypass grafting (CABG) remain a particularly high-risk population with impaired outcomes despite advances in surgical techniques. In this single-center, retrospective cohort study, 97 DD patients (2010–2015) were compared with 488 non-dialysis-dependent (NDD) controls. The primary endpoint was all-cause mortality; the secondary endpoint was major adverse cardiac and cerebrovascular events (MACCE). Median follow-up was 5.4 ± 2.1 years. DD patients had significantly higher perioperative mortality (10.3% vs. 3.1%, p = 0.002) and markedly reduced overall survival (OS) (40.8% vs. 82.1% at 5 years). Dialysis dependence conferred an 8.4-fold increase in mortality risk and a 2.6-fold increase in MACCE risk. Increasing age, diabetes, and critical preoperative state were independent predictors of an adverse long-term outcome. While arterial grafting improved survival in NDD patients, no comparable benefit was observed in DD patients, possibly due to vascular calcification, limited conduit availability, and reduced graft patency. EuroSCORE II adequately predicted perioperative mortality (AUC = 0.78 in DD patients) but demonstrated poor discriminatory power for long-term survival (AUC = 0.67 at 5 years). These findings highlight the urgent need for dialysis-specific risk models. Despite poor long-term prognosis, DD patients with low-risk EuroSCORE II profiles experienced the most relative benefit from CABG.

Heart transplantation is associated with major hurdles, including the limited number of available organs for transplantation, the risk of rejection due to genetic discrepancies, and the burden of immunosuppression. In this study, we demonstrated the feasibility of permanent genetic engineering of the heart during ex vivo perfusion. Lentiviral vectors encoding for short hairpin RNAs targeting beta2-microglobulin (shβ2m) and class II transactivator (shCIITA) were delivered to the graft during two hours of normothermic EVHP. Highly efficient genetic engineering was indicated by stable reporter gene expression in endothelial cells and cardiomyocytes. Remarkably, swine leucocyte antigen (SLA) class I and SLA class II expression levels were decreased by 66% and 76%, respectively, in the vascular endothelium. Evaluation of lactate, troponin T, and LDH levels in the perfusate and histological analysis showed no additional cell injury or tissue damage caused by lentiviral vectors. Moreover, cytokine secretion profiles (IL-6, IL-8, and TNF-α) of non-transduced and lentiviral vector-transduced hearts were comparable. This study demonstrated the ex vivo generation of genetically engineered hearts without compromising tissue integrity. Downregulation of SLA expression may contribute to reduce the immunogenicity of the heart and support graft survival after allogeneic or xenogeneic transplantation.

Background: Animal models are essential for translating diagnostic and therapeutic strategies into clinical practice and offer valuable insights into the pathophysiology of diseases such as aortic dissection. This study presents a novel acute in vivo large animal model of Stanford type A aortic dissection, combining open surgical access with endovascular techniques to leverage the advantages of both. The model aims to reproducibly simulate acute dissections in swine, providing a standardized platform for evaluating diagnostics, disease mechanisms, and treatment strategies. Methods: Six pigs underwent a standardized protocol to induce aortic dissection. Arterial pressure was monitored via femoral and carotid catheterization. A conventional sternotomy was performed, followed by tangential cross-clamping of the ascending aorta and a controlled incision proximal to the brachiocephalic trunk. The intima and the media were separated using a guidewire and catheter-based technique to create a false lumen. A re-entry tear was also established to allow for controlled intraluminal access. Animals were monitored for 12 h post-intervention, with serial blood sampling. At the end of the experiment, the animals were euthanized and the aortas harvested for macroscopic and histological analysis. Results: In all 6 animals, the placement of arterial catheters in femoral and carotid arteries, as well as the sternotomy, was established without any complications. The dissection model was successfully created in 5 out of 6 animals by clinical signs such as adventitial hematoma, macroscopic wall separation and/or decreased femoral blood pressure. One animal experienced complete aortic perforation. Five animals completed the full observation period of 12 h. Conclusion: A standardized, reproducible, and robust large animal model of acute Stanford type A aortic dissection using a hybrid approach was developed. This model closely simulates the clinical and pathological features of human aortic dissection, making it a valuable tool for preclinical research in diagnostics, pathophysiology, and treatment development.

Aims Non‐pharmacological therapies for acute decompensated heart failure (HF) and cardiogenic shock have evolved considerably in recent decades. Short‐term mechanical circulatory support (MCS) devices can be used as circulatory backup. While nearly all available devices use continuous flow, evidence indicates that pulsatile flow can be more effective. This study presents the first experimental use of a novel counter‐pulsatile left ventricular (LV) assist device (LVAD) with a primary focus on assessing its feasibility and effectiveness. Methods The pulsatile ventricular assist platform (pVAP) was applied in six porcine models of acute ischaemic HF with the inlet in the left atrium and the outlet in the aorta. HF was induced through stepwise ligation of the left anterior descending artery and its diagonal branches. The pVAP functioned driven by a conventional IABP console while LV pressure–volume (PV) loops and standard haemodynamics with the device OFF and ON were recorded. Absolute values and percent variations were compared using Mann–Whitney's U test and Wilcoxon's sign‐rank test. Results The device's output flow is frequency dependent, with an output flow of 2.64 ± 0.22 L/min at 80 bpm. Activation reduced the EDV [132 (90–145) vs. 118 (83–130) mL, P < 0.05], EDP 9 (6–10) vs. 6 (5–9) mmHg, P < 0.001], native cardiac output [CON, 3.64 (2.88–6.71) vs. 1.67 (1.24–2.48) L/min, P < 0.001] and myocardial oxygen consumption [pressure–volume area * heart rate (PVA*HR), 4592 (2944–9272) vs. 2901 (1915–4437) mJ, P < 0.001]. Contractility decreased, with right‐shifting the end‐systolic PV relationship (ESPVR) while ESP and forward cardiac output COF were constant. The mean arterial pressure increased [54 (48–60) vs. 49 (42–55) mmHg, P < 0.001] and mPAP decreased [10 (8–11) to 9 (7–10) mmHg, P < 0.01]. The PV loop shifted left and downward. No changes occurred in the passive‐elastic properties of the LV in diastole. Conclusions The pVAP reduced the LV mechanical load while increasing systemic pressures and reducing pulmonary pressures. Its functionality as an LVAD is characterised by consistent and predictable performance. Further research is necessary to elucidate the physiological and clinical impact of the device in animals and, subsequently, in humans. The pulsatile ventricular assist platform (pVAP) was connected to a membrane pump in six large swine models. The system, driven by a conventional intra‐aortic balloon pump console (IABP), was utilized to drain left atrial blood during systole and to eject the collected blood back into the ascending aorta during diastole. Following the induction of acute ischemic left ventricular failure, the system demonstrated an average flow of 2.64 L/min. The hemodynamic effect was characterized by an elevation of the mean arterial pressure, which coincided with a reduction in the mechanical and metabolic demands on the myocardium.

This paper presents an analysis of the possible performance of a proposed airborne rotor type electricity generator wind turbine design. The innovative design proposal by inventor is based on the rotation of the airborne structure with blades attached to the airborne zeppelin and thus it is called an airborne rotor generator. In this paper computational fluid dynamics analysis of a model close to the proposed design is carried out and the results are presented. The proposed design examples are set to produce 10-100KW. The electrical energy generated through two symmetrically placed alternators at both ends of the zeppelin is transferred to the ground-based system through the tethered cords used to also stabilize the system. Thus, an airborne rotor generator is formed.

This paper presents the results of a performance analysis conducted on an experimental airborne vertical axis wind turbine (VAWT), specifically focusing on the MAGENN Air Rotor System (MARS) project. During its development phase, the company claimed that MARS could generate a power output of 100 kW under wind velocities of 12 m/s. However, no further information or numerical models supporting this claim were found in the literature. Extending our prior conference work, the main objective of our study is to assess the accuracy of the stated rated power output and to develop a comprehensive numerical model to analyze the airflow dynamics around this unique airborne rotor configuration. The innovative design of the solid model, resembling yacht sails, was developed using images in the related web pages and literature, announcing the power coefficient (Cp) as 0.21. In this study, results cover 12 m/s wind and flat terrain wind velocities (3, 5, 6, and 9 m/s) with varying rotational velocities. Through meticulous calculations for the atypical blade design, optimal rotational velocities and an expected Tip Speed Ratio (TSR) of around 1.0 were determined. Introducing the Centroid Speed Ratio (CSR), which is the ratio of the sail blade centroid and the superficial wind velocities for varied wind speeds, the findings indicate an average power generation potential of 90 kW at 1.4 rad/s for 12 m/s and approximately 16 kW at a 300 m altitude for a 6 m/s wind velocity.

Objective: Oxidative stress has been considered to be one of the main causes for the development of pulmonary hypertension (PH) via leading alteration of pulmonary vasomotor tone induced by hypoxia. The aim of this study is to determine the serum paraoxonase-1 enzyme (PON-1) activity, arylesterase activity, the antioxidant-oxidant status in patients with PH and to compare with healthy controls. Material and Methods: Thirty five healthy ındividuals (mean age 45.7±5.9 years) as a control group and thirty eight patients (mean age 46.5±12.6 years) with a diagnosis of PH wereincluded in thestudy. Serum PON-1 and arylesterase activity, the total antioxidative capacity of plasma (TAC) and total oxidantstatus (TOS) were measured by using colorimetric methods. The Oxidative Stress Index (OSI) wascalculated as TOS/ TACX100. Results: Serum PON1 activity is significantly lower in PH patients when compared with healthy controls (p=0.001). The serum arylesterase activity and TAC, TOS and OSI status were similarin bothgroups. There is inverse correlation between serum PON1 activityand NYHA functionalcapacity (r:-0.649 p=0.001). Furthermore, PON1 activity of study patients are similarin the PH subgroups. Serum activity of PON1 wasfoundto bethe only independent parameter for the presence of PH in binary logistic regression analysis (OR 0.984, 95 % CI 0.977-0.992, p=0.001). Eight patients died follow up period (27.6±14.5 months) and none of theparametersincluding PON1 were associated with mortality. Conclusion: Serum PON1 activity of PH patients is lowerthanhealthypopulation, but does not predictmortality. Bangladesh Journal of Medical Science Vol.19(4) 2020 p.652-658

Herzunterstützungssysteme der neuesten Generation ermöglichen heutzutage erfolgreiche Therapiezeiten von mehreren Jahren. Eine große Anzahl der Patienten wird mittlerweile nicht mehr mit dem Ziel der Überbrückung bis zur Herztransplantation, sondern mit einer dauerhaften Therapie, „destination therapy“, versorgt. Trotz medizinischer und technischer Verbesserungen bleibt die Behandlung von Patienten mit einem Herzunterstützungssystem außerhalb herzchirurgischer Einheiten aufgrund der häufig bestehenden Multimorbidität sowie hämodynamischer und technischer Besonderheiten weiterhin eine Herausforderung. Die enge Anbindung an ein interdisziplinäres Team aus spezialisierten Ärzten und Kunstherzkoordinatoren gewährleistet eine lebenslange Unterstützung bei der medizinischen Versorgung dieser Patienten.

Zusammenfassung Herzunterstützungssysteme der neuesten Generation ermöglichen heutzutage erfolgreiche Therapiezeiten von mehreren Jahren. Eine große Anzahl der Patienten wird mittlerweile nicht mehr mit dem Ziel der Überbrückung bis zur Herztransplantation, sondern mit einer dauerhaften Therapie, „destination therapy“, versorgt. Trotz medizinischer und technischer Verbesserungen bleibt die Behandlung von Patienten mit einem Herzunterstützungssystem außerhalb herzchirurgischer Einheiten aufgrund der häufig bestehenden Multimorbidität sowie hämodynamischer und technischer Besonderheiten weiterhin eine Herausforderung. Die enge Anbindung an ein interdisziplinäres Team aus spezialisierten Ärzten und Kunstherzkoordinatoren gewährleistet eine lebenslange Unterstützung bei der medizinischen Versorgung dieser Patienten.