Search Results (283)

Degenerative mitral stenosis (MS) secondary to extensive mitral annular calcification (MAC) represents a growing clinical challenge in an aging population. These patients are often elderly, frail, and harbor a significant burden of comorbidities, rendering conventional mitral valve surgery prohibitively high-risk. While transcatheter mitral valve replacement (TMVR) has emerged as a potential alternative, the current evidence is only derived from single-arm observational registries. Therefore, the transition toward randomized controlled trials to define optimal patient selection and long-term prosthetic durability is necessary. This review examines the current landscape of TMVR for degenerative MS, focusing on the role of multimodal pre-procedural planning, procedural technique, and prevention of the principal complications. The integration of echocardiography and multi-slice computed tomography (MSCT) is essential for evaluating anatomical feasibility, particularly in predicting neo left ventricle outflow tract (neo-LVOT) obstruction, the primary determinant of procedural mortality. However, it is limited due to the absence of standardized protocol. We are showing the outcomes of off-label balloon-expandable aortic prostheses and dedicated TMVR system, which are the only two devices which data in patients with MS are available. Despite high technical success rates in specialized centers, complications, including paravalvular leak, valve thrombosis, and device migration, remain more prevalent than in aortic interventions. We present some tips and tricks to prevent and manage adverse events. TMVR represents a transformative frontier for inoperable patients with severe MAC. However, its routine clinical adoption requires further refinement of dedicated technologies and standardized imaging protocols to improve safety and bridge the gap between palliative medical therapy and definitive intervention. Full article

Swim bladders in some teleost fish can act as gas-filled cavities that oscillate under acoustic pressure and transfer the sound energy to the inner ears. Quantifying the resonance frequency and damping of these oscillations is useful for linking swim bladder mechanics to hearing-related and behavioural questions, but many established direct-measure approaches have relied on open-water deployments and careful avoidance of boundary reflections, making experiments logistically demanding and difficult to reproduce (e.g., requiring deep-water sites, careful control of surface/boundary reflections, and complex deployment geometries). This study presents a compact laboratory methodology for estimating swim bladder resonance properties using a closed, fully water-filled, stainless-steel impedance tube. Broadband pseudorandom excitation is applied via an end-plate shaker, and the acoustic response of the system is recorded using wall-mounted hydrophones. Resonance peaks are identified using power spectral estimates of recorded signals, allowing resonance frequency and quality factor to be extracted from the peak location and −3 dB bandwidth. The approach is first established using inflated latex balloons as surrogate encapsulated gas cavities, providing a controlled benchmark for repeatability and interpretation. It is then applied to recently euthanised brown trout (Salmo trutta), where clear resonance features attributable to the swim bladder are observed and show systematic variation with body size. A coupled finite element model reproduces the principal resonance behaviour under the experimental loading and supports interpretation of the measured peaks as swim bladder resonance. The results provide a validated foundation for subsequent non-invasive measurements on live, free-swimming fish, as well as for future applications where swim bladder condition may be relevant to management or conservation. Full article

Background: This study aims to compare the performance of machine learning (ML) models developed to predict long-term mortality risk in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (pPCI) and to investigate the prognostic value of novel inflammatory–metabolic indices. Methods: In this retrospective study, 329 consecutive STEMI patients who underwent pPCI (292 survivors, 37 deaths) were included. Five ML algorithms—Logistic Regression (LR), Random Forest (RF), Extreme Gradient Boosting (XGBoost), Support Vector Machines (SVM), and Artificial Neural Networks (ANN)—were developed for mortality prediction. Model performance was evaluated using accuracy, sensitivity, specificity, and the area under the receiver operating characteristic (ROC) curve (AUC). SHAP (Shapley Additive exPlanations) analysis was used to interpret model decision mechanisms. Results: The mortality group had significantly higher door-to-balloon time (DTBT), Systemic Inflammatory Response Index (SIRI), pan-immune-inflammation value (PIV), whereas body mass index (BMI), Prognostic Nutritional Index (PNI), and Advanced Lung Cancer Inflammation Index (ALI) values were significantly lower (p < 0.001). Among the ML models, the XGBoost algorithm achieved the best performance, with 98.99% accuracy, a ROC-AUC of 0.999, and 100% sensitivity, correctly identifying all mortality cases. SHAP analysis identified DTBT, albumin level, and ALI score as the strongest predictors of mortality, in that order. Conclusions: The XGBoost algorithm provides high accuracy and reliability for predicting long-term mortality in STEMI patients. Beyond DTBT, integrating novel indices—especially ALI and TyG—into ML models may serve as a powerful clinical tool for early identification of high-risk patients and improved risk stratification. Full article

Background: Patients with single-ventricle physiology represent a high-risk group for heart transplantation. Due to complex anatomical and physiological challenges, including multiple prior sternotomies, pulmonary artery abnormalities, and systemic consequences of altered circulation, they represent both a surgical and a clinical challenge. We aimed to analyze perioperative challenges, as well as early and long-term complications, in this specific group of patients. Methods: We performed a retrospective data analysis of a high-volume heart transplant center, focusing on patients with single-ventricle physiology who were scheduled for heart transplantation due to end-stage heart failure. We retrospectively analyzed the period from the beginning of the transplant program in November 1985 to the end of November 2024. Results: Among 1553 transplanted patients (adults and children), 29 were transplanted due to congenital heart disease (congenital valvular disease not included). In this group, nine patients were transplanted due to end-stage heart failure in the course of single-ventricle physiology. Age at transplantation ranged from 7 to 31 years (median, 17 years), and body weight ranged from 15 to 69 kg (median, 47.9 kg). All nine patients referred for heart transplantation presented with single-ventricle physiology. Their underlying congenital heart defects were heterogeneous and included hypoplastic left heart syndrome (HLHS), double-outlet left ventricle (DOLV), transposition of the great arteries (TGA) with associated ventricular septal defects (VSDs), atrial septal defects (ASDs), valvular abnormalities such as tricuspid and or pulmonary valve atresia or stenosis, systemic or atrioventricular valve regurgitation, and vascular abnormalities, including right-sided aortic arch, aortic coarctation, and pulmonary artery hypoplasia, stenosis, or occlusion, as well as associated pulmonary vascular abnormalities such as left pulmonary artery stenosis and MAPCAs. All patients had previously undergone staged palliative procedures, including Norwood, Hemi-Fontan, Fontan, bidirectional Glenn, modified Blalock–Taussig shunts, Bjork–Fontan, or pulmonary artery banding, often with repeated interventions such as balloon angioplasty, stent placement, or MAPCA closure. Extracardiac comorbidities were common and included coagulopathies, protein-losing enteropathy, hepatic dysfunction, and chronic venous insufficiency. Preoperative functional status was markedly impaired in all patients (NYHA III-IV, INTERMACS 3-4), with severely reduced exercise capacity and thrombotic events in several individuals. Perioperative transplant surgical strategies included femoral cannulation in four cases and standard aortic and caval cannulation in five cases. Pulmonary artery reconstruction was required in all patients. Extended donor pulmonary arteries were applied in eight cases, while a bifurcated Dacron prosthesis was utilized in one patient. Perioperative mortality was 33%, with three deaths attributed to bleeding and hemodynamic instability, while overall mortality was 44% including one late death unrelated to transplantation. Protein-losing enteropathy, although persistent in the immediate postoperative period, resolved in all surviving patients, underscoring the transformative impact of transplantation. Conclusions: These findings emphasize the importance of individualized surgical planning, extended donor pulmonary artery harvesting, and careful preoperative coordination. Heart transplantation remains a viable and life-extending option for selected single-ventricle patients, despite the significant technical and clinical challenges involved. Full article

Three-dimensional (3D) cultured cells can mimic the in vivo tumor microenvironment more accurately than conventional monolayer cultures. Therefore, they are essential in cancer research and drug discovery. However, high-sensitivity fluorescence imaging of 3D spheroids remains challenging owing to their limited contact with the observation surface and the low penetration depth of total internal reflection fluorescence microscopy (TIRFM). In this study, we developed a microfluidic device equipped with a water-driven balloon actuator that enables the hydrostatic compression of 3D-cultured spheroids. This system gently presses spheroids against a glass surface, significantly enhancing the contact area and improving TIRFM and epifluorescence imaging quality, with more evident improvement observed in TIRFM. Our results show that hydrostatic compression markedly enhances optical accessibility in spheroids while preserving cell viability and structural integrity. The method is designed to complement volumetric imaging techniques, including confocal and light-sheet microscopy, by enabling high-contrast visualization of cell–surface molecular dynamics. Although the current system focuses on surface accessibility, future studies will incorporate rotational mechanisms and automated pressure control to facilitate multi-angle, high-throughput imaging. This platform offers a promising strategy for the dynamic observation of cell–surface interactions in living 3D systems. Full article

Background: The use of resuscitative endovascular balloon occlusion of the aorta (REBOA) for hemorrhagic shock in the torso has become increasingly common as a bridge to definitive hemostasis. Hydrogen molecules, distributed throughout the bloodstream, alleviate ischemic injury but cannot reach ischemic organs during REBOA use. This study investigates whether intra-aortic irrigation with hydrogen-dissolved saline under REBOA use delivers hydrogen to the intestine in a swine hemorrhagic shock model. Methods: We induced volume-regulated hemorrhagic shock in a 40 kg female swine. Following this, hydrogen-dissolved saline irrigation was initiated through an intra-aortic catheter positioned distal to the REBOA balloon. Hydrogen concentration in the portal vein was determined in four models: controlled hemorrhagic shock with full REBOA inflation during the standard occlusion time, uncontrolled hemorrhagic shock with liver injury and full REBOA inflation during the extended occlusion time, uncontrolled hemorrhagic shock with liver injury and partial REBOA inflation during the extended occlusion time, and as the control model, controlled hemorrhagic shock with full REBOA inflation during the standard occlusion time with normal saline irrigation without hydrogen. Results: Hydrogen concentration in the portal vein was found to be 0.224 mg/L (13.998%) in the controlled hemorrhagic shock model with full REBOA inflation, 0.049 mg/L (3.063%) in the uncontrolled hemorrhagic shock model with liver injury and full REBOA inflation, 0.018 mg/L (1.125%) in the uncontrolled hemorrhagic shock model with liver injury and partial REBOA inflation, and 0.002 mg/L (0.015%) in the control model. These results demonstrate the presence of hydrogen in the portal vein under different REBOA applications. Conclusions: Increased hydrogen concentration in the portal vein indicated that hydrogen was delivered to the intestine. These findings suggest an approach for drug administration during REBOA use. However, further investigations are required to establish its application in clinical settings. Full article

Low-Speed near-space aerostats (e.g., stratospheric airships and high-altitude balloons) are low-speed unmanned aerial vehicles (UAVs) extensively utilized in communication coverage, remote sensing applications, environmental monitoring, aviation support, and other fields. A paramount challenge constraining their precise and stable operation is the leakage of buoyant gas, such as helium (He), in the harsh and unpredictable near-space environment. One of the primary causes of gas leakage is the degradation of their dedicated sealing rings. This study aims to clarify the aging mechanisms of high-performance rubber seals in near-space environments and establish a reliable service life prediction model to address the gas leakage risk of unmanned platforms. Two widely used high-performance rubber materials—ethylene propylene diene monomer (EPDM) and chloroprene rubber (CR)—were subjected to accelerated aging experiments under simulated near-space environment conditions. Their degradation was then quantified through performance degradation characterization, covering mass loss, hardness, elastic deformation, and tensile strength. A predictive model was established to estimate the mass loss rates and service life of the seals. The model revealed that EPDM exhibits superior performance to CR under near-space conditions: the aging behavior is strongly dependent on material composition, thickness, and preload, while being independent of outer diameter. Results show EPDM seals have a near-space service life of 300 days (50% longer than CR’s 200 days), with aging dependent on material composition, thickness (2 mm seals degrade 110% slower than 0.5 mm ones), and preload, but independent of outer diameter. These results provide actionable design guidelines for optimizing seal materials and geometries in aerostat pressure systems, thereby advancing the development of innovative low-speed UAV technologies and the successful application of these technologies in the emerging near-space field. These findings and the proposed methodology are directly applicable to sealing system optimization for various near-space unmanned platforms (e.g., stratospheric UAVs, high-altitude autonomous balloons), enhancing their long-duration operational reliability and mission success rate in extreme environments. Full article

Partial anomalous pulmonary venous return (PAPVR) with dual drainage is a very rare congenital heart anomaly. We report the case of a 6-year-old boy with PAPVR in whom both upper pulmonary veins (PVs) drain anomalously into the systemic venous circulation, while maintaining preserved intrapulmonary collateral venous connections with the remaining pulmonary veins draining into the left atrium. Careful balloon occlusion testing of the anomalous PVs was performed, simultaneously with measurements of pulmonary pressures and control angiography, proving the absence of venous congestion in the upper lung fields during the pulmonary venous phase. Transcatheter occlusion using vascular plugs was safely and successfully performed. Full article

Degraded mechanical properties in the aortic wall can lead to the formation of aortic aneurysms, potentially resulting in life-threatening ruptures. Current diagnostic criteria using maximum aortic diameter often fail to predict this critical moment, underscoring the need for more accurate patient-based prediction methods. A hospital-compatible experimental apparatus was designed for quasi-static ex vivo inflation testing of intact Ascending Thoracic Aortic Aneurysm (ATAA) specimens with 360° full-field three-dimensional digital image correlation (3D-DIC). Given hospital handling constraints, liquid pressurization was not feasible; instead, pressure was applied via a balloon-driven pneumatic system, and synchronized stereo imaging was used to measure surface displacement fields between 80 and 120 mmHg. The system was validated using a CT-derived ATAA silicone phantom. Full-field displacement measurements showed close agreement with finite element simulations, supporting the mechanical reliability of the apparatus and the repeatability of the measurement workflow. In addition, a frozen–thawed healthy porcine thoracic aorta was tested to demonstrate biological feasibility, particularly regarding the speckle application and DIC tracking, without aiming to extract tissue constitutive parameters. Overall, the setup provides a practical framework for acquiring full-field inflation-induced deformation data from intact aortic specimens in a hospital setting, enabling future studies on resected human ATAA tissue and model calibration that may contribute to more accurate methods for rupture prediction. Full article

The vulcanization of natural rubber latex (NRL) relies on accelerators to achieve effective crosslinking by a sulfur conventional vulcanizing system and desirable properties such as tensile strength and elasticity. This study investigates the synergistic effects of carcinogenic nitrosamine-safe accelerators to develop a high-performance and safe NRL vulcanization system. A synergistic combination of 0.36 phr Zinc dibutyldithiocarbamate (ZBEC), 0.36 phr Tetrabenzylthiuram disulfide (TBzTD), and a trace amount of Zinc diethyldithiocarbamate (ZDEC), 0.03 phr, demonstrated optimal performance, yielding superior tensile strength (22.13 MPa), elongation at break (1153%), and thermal stability (Tmax 384.15 °C). Notably, this formulation exhibited below the detectable level limits of hazardous nitrosamines (N-nitrosodimethylamine (NDMA) and N-nitrosodibutylamine (NDBA)). The synergistic nitrosamine-safe accelerator system offers a promising strategy for producing environmentally responsible and consumer-safe NRL products with enhanced mechanical and thermal properties. Full article

Introduction: Patients with major burn injuries are highly susceptible to hypothermia due to extensive skin loss, aggressive fluid resuscitation, repeated surgical procedures, and exposure during wound care. Hypothermia is associated with coagulation disorders, increased blood loss, impaired immune response, prolonged hospitalization, and increased mortality. When conventional warming strategies fail, intravascular temperature management systems may be employed, although they carry risks inherent to central venous catheters. Case Report: We report the case of a 26-year-old male with 66% total body surface area flame burns and inhalational injury, admitted to the Burns Intensive Care Unit with persistent hypothermia despite standard warming measures. An intravascular temperature management catheter was inserted via the femoral vein and successfully restored normothermia. Due to clinical instability, the catheter remained in situ beyond the recommended duration. During attempted catheter removal, significant resistance was encountered, raising concern for mechanical malfunction. Imaging confirmed catheter entrapment without fracture. Multidisciplinary management involving vascular surgery and interventional radiology enabled successful removal using endovascular snare techniques. A detached balloon fragment was identified and secured with venous stenting. Conclusions: This report describes the first documented case of complicated removal of an intravascular warming catheter due to balloon detachment in burn patients. Physicians using these devices should be aware of this possible complication and be prepared for its management. Full article

Metabolic dysfunction-associated steatotic liver disease (MASLD) has emerged as one of the greatest challenges for the modern public health system and serves as the foundation for the development of advanced stages, such as metabolic dysfunction-associated steatohepatitis (MASH), which may progress to fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). MASLD and type 2 diabetes mellitus (T2DM) mutually exacerbate one another. MASLD increases the incidence of T2DM and the risk of complications in patients already affected. T2DM accelerates progression to MASH, which has become the second leading cause of liver transplantation and end-stage liver disease, and is associated with hepatic decompensation, cirrhosis, HCC, chronic kidney disease, and cardiovascular disease. MASLD and MASH are strongly linked to T2DM and obesity, pathogenesis including genetic polymorphisms, environmental factors, and multiple metabolic disturbances: insulin resistance (IR), gut dysbiosis, altered adipokine signaling, such as reduced adiponectin alongside increased pro-inflammatory cytokines. Inflammation plays a central role in the development of HCC in MASH, even in the absence of significant fibrosis. The Fibrosis-4 index (FIB-4) should be used as a first-line noninvasive tool to assess fibrosis risk. Additionally, ultrasound-based transient elastography (FibroScan) supports clinicians in assessing steatosis and fibrosis severity. Histologically, MASH is characterized by steatosis, lobular inflammatory changes, and ballooning degeneration of hepatocytes, with or without associated fibrosis. Accurately diagnosing and stratifying MASLD based on fibrosis risk is crucial to identify patients who may benefit from pharmacological treatment or can be managed only with lifestyle interventions. Patients should attain above 10% weight loss through lifestyle modifications. Resmetirom is recommended in F2/F3 fibrosis stages. For treating T2DM, glucagon-like peptide-1 receptor agonists and coagonists, sodium–glucose cotransporter-2 inhibitors, metformin (if glomerular filtration rate exceeds 30 mL/min), and insulin (in decompensated cirrhosis) are preferred. Clinical insights derived from trials are expected to optimize quality of life and long-term outcomes in patients with MASH. Full article

Type 2 myocardial infarction (T2MI) is defined as myocardial necrosis caused by an imbalance between oxygen supply and demand in the absence of acute atherothrombotic coronary occlusion/erosion. Unlike type 1 myocardial infarction (T1MI), T2MI comprises a heterogeneous group of clinical scenarios, often triggered by systemic or cardiac conditions, and it frequently affects elderly patients with a high burden of comorbidities. T2MI often underline multivessel coronary artery disease and, despite its growing clinical relevance, the diagnostic and therapeutic approach to T2MI remains challenging and lacks standardized recommendations. In this review, we present an updated and a comprehensive synthesis of current evidence on the diagnosis and management of T2MI, focusing on the role of coronary angiography and interventional strategies. We discuss the utility of high-sensitivity cardiac biomarkers, imaging modalities, and clinical risk scores to guide patient selection for invasive evaluation. Specific attention is given to conservative and alternative revascularization approaches—including drug-coated balloon angioplasty and stentless percutaneous coronary intervention (PCI)—in frail and high-bleeding-risk patients. The review emphasizes the need for individualized decision-making in a population where standard invasive strategies may not always be appropriate, and where a tailored balance between ischemic and hemorrhagic risk is crucial. Full article

Intracardiac echocardiography (ICE) is increasingly recognized as a valuable imaging modality in structural heart interventions, offering high-resolution, real-time visualization from within the cardiac chambers. Originally developed for electrophysiologic procedures, ICE has expanded its use across a broad spectrum of structural interventions, including atrial septal defect (ASD) and patent foramen ovale (PFO) closure, left atrial appendage occlusion (LAAO), transseptal puncture guidance, transcatheter edge-to-edge repair (TEER), balloon mitral valvuloplasty, and both mitral and tricuspid valve therapies. This review outlines the current role and technical principles of ICE, with an emphasis on catheter design, image acquisition protocols, and the emerging potential of 3D ICE. Comparisons with transesophageal echocardiography (TEE) and fluoroscopy are discussed, highlighting ICE’s ability to support minimally invasive, sedation-sparing procedures while maintaining procedural precision. We provide a focused analysis of ICE-guided applications in specific clinical scenarios, emphasizing its role in anatomical assessment, device navigation, and intra-procedural monitoring. Data from recent clinical studies and registries are reviewed to assess safety, feasibility, and outcomes. Practical considerations including operator learning curve, workflow integration, and limitations such as cost and field of view are also addressed. Lastly, we explore future directions including advanced 3D imaging, fusion imaging, artificial intelligence integration, and robotic catheter systems. Full article

Background/Objectives: Functional impairment of the complex motility system in the upper gastrointestinal tract is high in patients suffering from obesity and even higher after metabolic bariatric surgery (MBS). Sleeve gastrectomy (SG) and gastric bypass (GB) represent the most common MBS procedures worldwide. Despite procedural standardization, no diagnostic method is able to depict the functional consequences resulting from intraoperative anatomical changes during MBS. This pilot study was conducted to reveal immediate intraoperative functional effects of MBS on the anti-reflux barrier in SG and GB. Methods: A prospective analysis was performed on consecutive patients with informed consent for MBS. A standard protocol for each procedure was established prior to study onset to analyze functional parameters at the lower esophageal sphincter (LES). Measurements were conducted intraoperatively during minimally invasive SG and GB. Distensibility index (DI), intra-balloon pressure, diameter (Dmin), and minimal cross-sectional area (CSA) at the LES served as points of interest for analyzation. Results: Intraoperative evaluation was performed successfully in 40 patients and no directly related adverse events were reported. DI and Dmin intraoperatively significantly increased immediately in SG (2.1 mm²/mmHg (±0.5) vs. 2.9 mm²/mmHg (±1.3), 95% CI: −1.6 to −0.14, p = 0.023 and 12.0 mm (±1.2) vs. 13.9 mmH (±2.8), 95% CI: −3.6 to −0.2, p = 0.028, respectively) whereas GB did not affect functional measurements. Conclusions: Sleeve gastrectomy immediately and significantly influences the LES and increases the opening area whereas gastric bypass surgery appears not to influence LES distensibility or opening diameters. Intraoperative standardized EndoFLIP^TM measurements are feasible and safe and add additional real-time information during MBS. Full article