International Journal of Artificial Organs最新文献

Background: Mitral transcatheter edge-to-edge repair (M-TEER) has improved outcomes in selected patients with secondary mitral regurgitation (MR). However, patients can experience progressive heart failure (HF), subsequently requiring durable mechanical support with left ventricular assist devices (LVAD). Optimal management strategies for M-TEER devices during LVAD implantation remain unclear.

Methods: This retrospective multicenter study included consecutive patients who underwent LVAD implantation following prior M-TEER for secondary MR at three tertiary Italian centers (2012-2022). Patients were categorized based on clip management during LVAD surgery: surgical removal, retention with elevated residual mitral gradient (⩾5 mmHg), or retention with normal gradient (<5 mmHg). The primary endpoint was a composite of all-cause mortality or HF hospitalization.

Results: A total of 28 patients were included, with a median age of 64 years; 86% were male. Median interval from M-TEER to LVAD implantation was 378 days. Clip removal was performed in 5 patients (18%), while 23 (82%) retained the clip (3 with elevated and 20 with normal gradients). MR improved significantly post-LVAD implantation in all groups. In-hospital mortality was 11%, higher (40%) in patients undergoing clip removal. At a median follow-up of 35 months, the composite endpoint occurred in 63% of patients without significant differences between groups (p = 0.60).

Conclusions: LVAD implantation following M-TEER therapy is feasible, with acceptable perioperative and mid-term outcomes. Retaining the clip is safe, particularly if residual MV gradients are low.

Background: The ideal dialysate potassium concentration for patients with hyperkalemia undergoing maintenance hemodialysis is debated. While low-potassium dialysate enhances potassium removal, a steep serum-todialysate potassium gradient may provoke arrhythmias. This study aimed to assess the efficacy of a two-phase dialysate potassium profiling strategy.

Materials and methods: Patients aged 18-60 years with end-stage renal disease and predialysis hyperkalemia were randomized into two groups for twice-weekly hemodialysis. Group A received 2 mEq/L potassium dialysate for the first hour, followed by 0 mEq/L for the next 3 h. Group B received a constant 2 mEq/L potassium dialysate throughout the 4-h session. Serum potassium was measured pre-dialysis and hourly during the session. Patients were monitored for cardiac arrhythmias.

Results: Of 145 patients screened, 60 were enrolled (30 per group). The majority were male (66.7% in Group A and 56.7% in Group B), with over 50% having diabetes and 85% hypertension, indicating high cardiovascular risk. Predialysis potassium levels were similar (6.00 ± 0.3 mEq/L in Group A vs 5.98 ± 0.34 mEq/L in Group B). Group A achieved significantly lower post-dialysis potassium levels (3.48 ± 0.22 mEq/L) than Group B (3.72 ± 0.42 mEq/L; p = 0.008). One case of ventricular ectopy was observed in each group, both managed conservatively.

Conclusion: Two-phase dialysate potassium profiling effectively lowers serum potassium more than a fixed approach, without a significant increase in arrhythmic events, supporting its use in managing hyperkalemia in hemodialysis patients.

Forty five years morbidly obese male with prosthetic mitral and aortic valve referred to our hospital with dengue shock syndrome. He had recurrent ventricular arrhythmias required multiple shock and short cycle of cardiopulmonary resuscitation (CPR). He was supported with high dose vasopressors and mechanical ventilation. Two-dimensional Echocardiography showed severe left ventricular (LV) dysfunction with left ventricular ejection fraction (LVEF) 8%-10% and mild increase in the gradient across aortic and mitral valve however there was no para-valvular leak or vegetations. Venoarterial (VA) extracorporeal membrane oxygenation (ECMO) was initiated along with continuous renal replacement therapy (CRRT) using Oxiris^® filter in view of persistent ventricular arrhythmia, acute kidney injury (AKI) Grade 3 and severe acute hepatic dysfunction. The major concerns were severe myocardial dysfunction and malignant arrhythmias with impending cardiac arrest warranting the need for VA ECMO support while prosthetic valves especially aortic, uncertainty regarding myocardial dysfunction whether pre-existing or dengue induced and severe dysfunction of other organs were challenges for decision to initiate ECMO. This case describes successful ECMO management and challenges due to prosthetic valve as well as pre-existing severe myocardial dysfunction and concurrent other organ dysfunction.

Objective: This study aims to evaluate the clinical and demographic factors influencing the restoration of sinus rhythm and postoperative outcomes in patients undergoing bipolar radiofrequency ablation (RFA) concomitant with mitral valve surgery. By analyzing the associations between rhythm outcomes, mortality, and patient characteristics, this study seeks to identify predictors of ablation success and provide valuable insights into optimizing treatment strategies for atrial fibrillation in this high-risk patient population.

Methods: Demographic and clinical characteristics of the patients were analyzed. Postoperative electrocardiography (ECG) findings during the first year after surgery were used to classify patients into two groups: those who achieved sinus rhythm (SR) and those who remained in atrial fibrillation (AF). Additionally, patients were categorized into survivors and non-survivors within the first postoperative year for statistical comparisons.

Results: The overall rate of sinus rhythm (SR) restoration within the first year after radiofrequency (RF) ablation was 70.2% (n = 85). When comparing patients who achieved SR with those who remained in atrial fibrillation (AF) postoperatively, the AF group exhibited significantly larger preoperative ascending aortic diameters, left atrial diameters, and interventricular septal thicknesses, along with lower ejection fractions on transthoracic echocardiography (TTE) (p = <0.001, 0.015, 0.012, and 0.024, respectively).

Conclusions: Radiofrequency ablation is a safe and effective method for maintaining long-term sinus rhythm, with no additional complications. It is associated with a low risk of morbidity and thromboembolic complications.

Purpose: To date, there are no effective therapeutic strategies for hepatocellular carcinoma (HCC). Traditionally, researches on HCC were carried out using hepatocellular carcinoma cells, organoids, and animal models. However, these models cannot accurately replicate the pathophysiological conditions underlying the onset and progression of human HCC. Therefore, more effective disease models are needed to study HCC.

Methods: Ten disease livers from HCC patients who underwent transplantation were subjected to normothermic machine perfusion (NMP) via the hepatic artery and portal vein in vitro. Perfusion parameters, blood gas levels, and contrast-enhanced ultrasound (CEUS) were continuously monitored to assess alterations in tumor activity. RNA sequencing (RNA-seq) and next-generation sequencing (NGS) of circulating tumor DNA (ctDNA) were employed to assess the preservation of hepatic tissue integrity and tumor mutational profiles during in vitro perfusion. Oxaliplatin +5-FU was used to conduct the liver cancer treatment research.

Results: Normothermic machine perfusion successfully maintained liver survival for 92 h in vitro. Contrast-enhanced ultrasound can be used to assess alterations in tumor and liver activity during normothermic machine perfusion. The sequencing analysis revealed that normothermic machine perfusion (NMP) effectively preserved hepatic tissue integrity while retaining tumor genomic stability. The normothermic machine perfusion model of HCC can be used for the study of anti-cancer therapy.

Conclusions: Contrast-enhanced ultrasound can monitor alterations in tumor and liver activity, while normothermic machine perfusion can sustain the long-term survival of the liver in vitro, thus maintaining normal tumor characteristics. Therefore, this model provides a novel approach for studying tumor therapy.

Background: High shear rate and non-physiological turbulent flow caused by bileaflet mechanical heart valves (BMHVs) lead to platelet activation and adhesion, which can cause rapid thrombus growth and severe consequences.

Methods: This study employed computational modeling to analyze the effect of surface texture on flow field around the BMHVs. The textures' positional, geometric, and dimensional parameters were optimized based on flow field analysis. The textured BMHVs were then implanted in sheep for 6 months, with pyrolytic carbon BMHVs serving as the control group.

Results: The textured BMHVs significantly reduced high-velocity, low-velocity, high turbulent shear stress, and high shear rate regions in the flow field. Post-implantation, the experimental groups with textured BMHVs exhibited lower levels of platelet activation and neither the intrinsic nor extrinsic coagulation cascade reactions were activated in the sheep. Detailed observations revealed an absence of erythrocyte or platelet adhesion within the grooved texture regions, with minimal adhesion at the peripheral edges of the textured areas.

Conclusion: The optimized surface textures on BMHVs effectively reduce adverse flow conditions and platelet activation, potentially decreasing the need for anticoagulant therapy and minimizing the associated bleeding risks. These findings are crucial for enhancing the long-term safety and efficacy of BMHV implantation.

Lung cancer (LC) is one of the leading causes of cancer related deaths worldwide and early recognition is critical for enhancing patient outcomes. However, existing LC detection techniques face challenges such as high computational demands, complex data integration, scalability limitations, and difficulties in achieving rigorous clinical validation. This research proposes an Enhanced Hyper Tuning Deep Learning (EHTDL) model utilizing bioinspired algorithms to overcome these limitations and improve accuracy and efficiency of LC detection and classification. The methodology begins with the Smooth Edge Enhancement (SEE) technique for preprocessing CT images, followed by feature extraction using GLCM-based Texture Analysis. To refine the features and reduce dimensionality, a Hybrid Feature Selection approach combining Grey Wolf optimization (GWO) and Differential Evolution (DE) is employed. Precise lung segmentation is performed using Mask R-CNN to ensure accurate delineation of lung regions. A Deep Fractal Edge Classifier (DFEC) is introduced, consisting of five fractal blocks with convolutional layers and pooling to progressively learn LC characteristics. The proposed EHTDL model achieves remarkable performance metrics, including 99% accuracy, 100% precision, 98% recall, and 99% F1-score, demonstrating its robustness and effectiveness. The model's scalability and efficiency make it suitable for real-time clinical application offering a promising solution for early LC detection and significantly enhancing patient care.

Platelet derived prothrombotic microparticles (MP) have been associated with hemocompatibility related adverse events in patients with continuous flow left ventricular assist devices; little is known with the contemporary Impella platform micro-axial flow pumps. Indeed, the extended duration of support provided by the Impella 5.5 calls for a specific evaluation. We report for the first time two patients in whom MP have been assessed during Impella 5.5 and concomitant dual antiplatelet and direct thrombin inhibitor therapy. Interestingly, the patients showed significantly different profile in overall MP release (peak: 78.1% vs 2.7%), which was not correlated to lactate dehydrogenase nor platelet count. The patient with the higher values suffered from minor stroke 4 days after pump removal, when systemic anticoagulation with Bivalirudin had been stopped. These preliminary data might envision a new predictor of hemocompatibility related adverse events in patients with Impella, and a rethinking on the post support antithrombotic strategy.