Artificial organs最新文献

Purpose: Reoperative durable left ventricular assist device (LVAD) insertion after coronary artery bypass grafting (CABG) is challenging due to potential injury to bypass grafts, great vessels, or the right ventricle (RV). We sought to compare the less invasive (LI) approach to the full sternotomy (FS) technique for LVAD implantation in patients with a prior history of CABG.

Methods: From March 2012 to April 2023, 29 patients with a history of CABG underwent reoperative LVAD implantation: Group FS, N = 16, and Group LI, N = 13. The LI approach includes an upper hemisternotomy and left thoracotomy without dissecting around the RV and bypass grafts.

Results: The median age was 68 years in Group FS and 70 years in Group LI (p = 0.83). HeartMate II was only used in group FS (FS: 56.3% [N = 9] vs. LI: 0%), whereas HeartWare (FS: 31.3% [N = 5] vs. LI: 53.8% [N = 7]) and Heartmate 3 (FS: 12.5% [N = 2] vs. LI: 46.2% [N = 6]) were used in both groups. None of the patients experienced intraoperative injury of bypass grafts. In isolated LVAD implantation, cardiopulmonary bypass time was comparable between groups (FS: 92 [68, 96] min vs. LI: 82 [61, 96] min, p = 0.33). The incidence of severe RV failure requiring mechanical support was lower in Group LI (FS: 43.8% [N = 7] vs. LI: 0%, p = 0.02). Hospital mortality was numerically lower in the LI group (FS: 31.3% [N = 5] vs. LI: 9.1% [N = 1], p = 0.35). One-year estimated survival rates were not significantly different (FS: 68.8% ± 11.6% vs. LI: 81.8% ± 11.6%, p = 0.85).

Conclusions: The less invasive technique for reoperative LVAD insertion after CABG may improve outcomes by reducing RV failure.

Introduction: Terminal heart failure is often associated with end-stage kidney disease. Due to advantages concerning patient independence, peritoneal dialysis (PD) is an alternative to conventional hemodialysis treatment. As left ventricular assist device implantations continuously increase, data on combined PD and LVAD is rare. We present the first and largest cohort study on this exclusive patient cohort.

Methods: A retrospective study was conducted on patients who underwent LVAD implantation at a high-volume heart failure center from 2000 to 2024. Adverse events were analyzed according to the INTERMACS classification.

Results: A total of nine patients were identified as undergoing PD on LVAD therapy. Mean age at the time of LVAD implantation was 67 years. Main cause of kidney disease was cardio-renal syndrome (67%). In all patients, PD therapy was established before LVAD implantation. Mean time on PD before LVAD implantation was 72 months. None of the patients were weaned from dialysis nor were converted to conventional dialysis. Four patients experienced driveline infection. Three patients suffered an infection of their PD catheter. A combination of PD and DL infection was detected in two cases. None of these infections were associated with the same pathogens. Mean survival after LVAD + PD was 56.5 months.

Conclusion: Peritoneal dialysis has advantages over hemodialysis including fewer bloodstream infections, fewer hemodynamic shifts, and the comfort of the ambulant setting. This study illustrates that PD in LVAD patients is feasible and long-term support up to several years is achievable without major complications.

Background: Cardiogenic shock in left main coronary artery acute myocardial infarction patients has high mortality rates. This study investigates the association between left ventricular size and outcomes in these patients treated with veno-arterial extracorporeal membrane oxygenation.

Methods: This retrospective single-center study examined patients who underwent percutaneous coronary intervention for left main coronary artery acute myocardial infarction and developed refractory cardiogenic shock between April 2013 and August 2021. Baseline characteristics and echocardiographic assessments were conducted 24-48 h after veno-arterial extracorporeal membrane oxygenation initiation. Patients were divided into two groups: small left ventricle (S-group, ≤ 23 mm/m² for males and ≤ 26 mm/m² for females, n = 11) and regular left ventricle (R-group, n = 22). The primary outcome was a 1-year survival. The analysis included survival and adjusted multivariate Cox proportional hazards modeling.

Results: The S-group showed a significantly higher mortality rate during support (63.6% vs. 4.5%, p = 0.001). In the unadjusted survival analysis, the 1-year survival rate was significantly lower in the S-group (9.0% [95% CI, 1.4-58.9] vs. 59.1% [95% CI, 41.7-83.6], p < 0.01). After adjusting for confounders, multivariate Cox analysis identified a small left ventricle (adjusted HR 8.38, 95% CI 2.33-30.16, p = 0.001), advanced age (per 10-year increase, adjusted HR 2.35, 95% CI 1.39-3.98, p = 0.001), and lower baseline left ventricular ejection fraction (per 10% decrease, adjusted HR 0.48, 95% CI 0.26-0.88, p = 0.018) as significant predictors of 1-year all-cause mortality.

Conclusions: In patients with severe cardiogenic shock following left main coronary artery acute myocardial infarction requiring veno-arterial extracorporeal membrane oxygenation, a small left ventricle is associated with a poor prognosis.

Background: Acute-on-chronic liver failure (ACLF) is associated with high short-term mortality of up to 40%. Albumin dialysis is a therapeutic option that can be used to bridge patients with ACLF to liver transplantation or recovery.

Methods: This retrospective cohort study was conducted to determine the effectiveness and adverse effects of open albumin dialysis (OPAL) by comparing the biochemical and clinical variables of model for end-stage liver disease (MELD)-matched ACLF patients who received one of three treatments: OPAL plus standard medical treatment (SMT; 22 patients), Prometheus dialysis fractionated plasma separation and adsorption (FPSA) plus SMT (41 patients), or hemodialysis plus SMT (24 patients) at the University Hospital Essen.

Results: OPAL treatment significantly reduced liver function tests such as bilirubin (p = 0.0001) and creatinine levels (p = 0.049). Therefore, OPAL therapy significantly reduced the MELD score (p = 0.001) and the Chronic Liver Failure Consortium (CLIF-C) ACLF (p = 0.0005) score. In both extracorporeal liver support groups, the decrease in MELD score was significantly stronger than that achieved with SMT (OPAL vs. SMT, p = 0.002; Prometheus vs. SMT, p = 0.0001; OPAL vs. Prometheus p = 0.90). In comparison to the SMT group, survival rates after 14 and 30 days were significantly higher in the Prometheus group (p = 0.0008 and 0.03) and tended to be better in the OPAL group, although statistical significance was not reached (p = 0.06 and p = 0.11).

Conclusions: Our analysis revealed OPAL is an efficient method of albumin dialysis yielding a reduction of bilirubin and creatinine levels and improving clinical scoring in ACLF patients. OPAL as well as Prometheus were associated with a stronger reduction of relevant biochemical variables of liver function and amelioration in clinical scoring in comparison to SMT. However, it should be considered that patients from the SMT group were older and experienced progressive ACLF with high mortality risks compared to the patients from the OPAL and Prometheus groups. Thus, when interpreting the study results, several limitations including small sample size and heterogeneity of the treatment groups due to the lack of randomization should be taken into account.

Background: Tissue engineering is an interdisciplinary field that integrates therapeutic agents, cells, biomaterials, and methodologies to regenerate damaged tissues. In bone tissue engineering, selecting and modifying materials to enhance mechanical strength, porosity, and pore size is critical for developing scaffolds that effectively support tissue regeneration.

Methods: A systematic review was conducted using Scopus, employing keywords such as "biomaterials for scaffold," "polymer for scaffold," and "freeze-drying synthesis method." After a rigorous screening and review process, 26 studies published between 2014 and 2024 were included in the analysis.

Results: The analysis revealed that lower freeze-drying temperatures lead to denser and more compact scaffold structures due to slower ice crystal formation. These scaffolds exhibit interconnected porous architectures critical for nutrient diffusion and cell infiltration. Key improvements in compressive strength and porosity were observed, making these scaffolds suitable for bone tissue engineering applications.

Conclusions: Freeze-drying is a sustainable and effective method for scaffold fabrication, enabling the use of eco-friendly biomaterials. The resulting scaffolds demonstrate superior compressive strength and high porosity, facilitating effective cell attachment and proliferation. This study underscores the potential of freeze-drying methodologies in advancing scaffold design for bone tissue regeneration.

Background: High rotational pump speeds in percutaneous mechanical circulatory support (pMCS) devices frequently result in hemolysis. Consequently, in vitro hemolysis testing for newly developed devices is essential to mitigate this significant risk. This study compared the degree of hemolysis induced by the Second Heart Assist Whisper pMCS at its maximum pump speed, representing the worst-case scenario, with that of the Impella CP, following American society for testing and materials standards.

Methods: Five Whisper devices were tested at 10000 RPM, while a comparator Impella CP was operated at 44 133 ± 606 RPM to match the Whisper's flow rate. Both devices were evaluated in two identical in vitro blood circulatory loops using citrated bovine blood. Hemolysis was analyzed by the tetramethylbenzidine method.

Results: The change in plasma free hemoglobin (ΔpfHb) was significantly greater with the Impella CP than with the Whisper (p < 0.01). Both devices caused a steady increase in pfHb, with significant differences after 60 min of in vitro testing (p < 0.01). The Whisper and Impella CP differed significantly in normalized index of hemolysis (0.088 ± 0.022 vs. 0.194 ± 0.029 g/100, p < 0.01) and modified index of hemolysis (9.72 ± 2.4 vs. 20.83 ± 3.5, p < 0.01).

Conclusion: The Whisper exhibited superior hemolytic performance to that of the Impella CP under identical hemodynamic conditions. Our newly designed blood circulatory loop and these benchmark values will aid future in vitro hemolysis testing for pMCS devices.

Background: Patients with pre-existing severe cardiovascular comorbidities are often deemed ineligible for potentially life-saving thoracic surgeries and are referred to other conservative therapies. However, this patient population may theoretically benefit from the timely perioperative implantation of temporary mechanical circulation support (tMCS) to both mitigate the surgical stress and stabilize hemodynamics. We performed a scoping review to summarize the evidence regarding the use of tMCS in thoracic surgery.

Methods: We conducted a systematic search across PubMed/MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, Web of Science, Scopus, and Google Scholar from their inception, aided by a search string encompassing a combination of terms for the key research concepts: i) tMCS devices; ii) thoracic surgery procedures (except lung transplantation); and iii) the adult population.

Results: Fifteen studies pertinent to the research question, which summarized data from 28 patients, were retrieved for inclusion. In 14 patients, tMCS implantation occurred as a "pre-emptive" strategy, while the remaining patients had tMCS implanted either intra and/or postoperatively as a "bail-out" strategy. Specifically, 14 patients required an intra-aortic balloon pump, 10 veno-arterial extracorporeal membrane oxygenation, two required a multidevice strategy, and one cardiopulmonary bypass. The relative risk analysis revealed that the mortality rate in the pre-emptive group was half that of the bail-out group. Additionally, the risk of both infectious and vascular complications was lower in the pre-emptive group compared to the bail-out tMCS strategy.

Conclusion: We found that the timely implantation of tMCS in thoracic surgery-either to mitigate patients' heightened cardiovascular risk or as a rescue strategy in the event of life-threatening surgical complications-may lead to better patient outcomes, as well as allowing them to undergo curative surgery with an acceptable safety profile, characterized by overall good survival rates and a low incidence of device-related complications.

Introduction: Liver transplantation (LT) is the sole curative option for liver failure and other primary liver conditions. However, the limited number of suitable donors compared with the growing number of patients requiring LT remains a leading cause of mortality among those on the waiting list. This has resulted in the expansion of criteria for donor eligibility. The sequential combination of ex situ reperfusion, dHOPE, and NMP helps reduce the occurrence of ischemia-reperfusion injury and assess organ viability prior to transplantation.

Methods: This is a retrospective, single-arm, single-center study including all cases of liver grafts that underwent sequential perfusion between October 2021 and July 2024. Eligibility criteria for sequential perfusion were extended criteria DBD with macrosteatosis > 35%, use of high-dose vasopressors during donor ICU stay or episodes of cardiac arrest, hemodynamic instability during procurement, prolonged ischemia time for logistic reasons, as well as DCD showing prolonged fWIT, flow alteration during normothermic regional perfusion (NRP), and DCDs in Maastricht 2 class. Viability was assessed following the Groeningen group criteria.

Results: Thirty-three cases were included and 16 met the viability criteria at the end of the sequential perfusion and were transplanted. One patient developed an early allograft failure (EAF) and another a primary nonfunction (PNF). All the other patients had a regular postoperative course, with no retransplantation, 56% of the cohort showing no postoperative complication and all currently in good standing, median follow-up 19 months (range 4-39).

Conclusions: Sequential dHOPE and NMP is a strategy that can help assessing both viability and functionality of liver grafts from high-risk donors, expanding the donor pool and increasing the opportunities for patients on the waiting list to get a transplant.