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Although extracorporeal membrane oxygenation (ECMO) systems have been used to provide temporary support for patients with severe respiratory or cardiac failure, they are often bedridden, in part because of their bulky size which relies solely on an unlimited source of wall oxygen. However, there is an unmet clinical need for ambulatory ECMO which necessitates downsizing the ECMO system. We sought to develop a new oxygenator to reduce the dependence on the oxygen supply source. The proposed oxygenator features a dual-chamber gas exchangers, with one chamber primarily responsible for carbon dioxide removal using ambient air and a subsequent chamber primarily responsible for oxygen transfer using pure oxygen. Computational fluid dynamics was used to analyze the blood flow field to avoid adverse stagnation and optimize gas exchange performance. Bovine blood was used for in vitro gas transfer test. This new oxygenator demonstrated the capability to provide adequate respiratory support (both carbon dioxide removal and oxygen transfer) to adult patients at blood rate of 4-6 L/min with an oxygen supply of only 2 L/min. The reduced use of oxygen with this new oxygenator may pave the way for the development of potable ECMO systems., Competing Interests: Disclosure: Z.J.W. and B.P.G. disclose financial interest in Abiomed-Breethe, Inc. and intellectual property for ECMO systems and blood pumps. J.Z. discloses financial interest in intellectual property for ECMO systems and blood pumps. The other authors have no conflicts of interest to report., (Copyright © ASAIO 2025.)

The power-law model, originally developed for shear-induced hemolysis, has been used to predict shear-induced platelet activation and receptor shedding. However, its empirical nature lacks mechanistic explanations and violates physical reality by not imposing an upper limit, often leading to inaccuracies. Recent studies suggest that the mechanical pulling of platelet GPIb-IX complex triggers the unfolding of its mechanosensitive domain, a crucial process to platelet activation, which can be explained by Bell's model of bond unbinding under force. Motivated by these findings, we propose a novel mathematical model for shear-induced platelet activation (P-selectin) and shear-induced platelet receptor (glycoprotein Ibα [GPIbα], GPVI, and GPIIb/IIIa) shedding based on the principle of bond unbinding. The model was examined using experimental data from previous studies in which blood samples were exposed to different combinations of constant shear stress and exposure time. The new model demonstrated an excellent fit with experimental data with an overall coefficient of determination R2 >0.8, mapping the trends in platelet activation and receptor shedding (except for GPIIb/IIIa) across a range of shear conditions. This new model not only addresses the intrinsic upper bound error in the power-law model but also provides a theoretical foundation into blood damage under shear stress., Competing Interests: Disclosure: The authors have no conflicts of interest to report., (Copyright © ASAIO 2025.)

Background: Improvement in gene modifications of donor pigs has led to the prevention of early cardiac xenograft rejection and significantly prolonged cardiac xenograft survival in both heterotopic and orthotopic preclinical non-human primate (NHP) models. This progress formed the basis for FDA approval for compassionate use transplants in two patients., Methods: Based on our earlier report of 9-month survival of seven gene-edited (7-GE) hearts transplanted (life-supporting orthotopic) in baboons, we transplanted 10 gene-edited pig hearts into baboons (n = 4) using non-ischemic continuous perfusion preservation (NICP) and immunosuppression regimen based on co-stimulation blockade by anti-CD40 monoclonal antibody. This pivotal study expands on the 7-GE backbone, with 3 additional gene edits, using 10-GE pigs as donors to baboon recipients., Results: 10 GE cardiac xenografts provide life-supporting function up to 225 days (mean 128 ± 36 days) in a non-human primate model. Undetectable or latent porcine cytomegalovirus (PCMV) does not influence cardiac xenograft survival in this study but still needs more exploration with a larger cohort. Xenograft histology demonstrates adipose (Fat) deposition (n = 1), chronic vasculopathy (n = 1), micro and macro thrombosis, and acute cellular rejection (n = 1)., Conclusions: These data demonstrate that 10 GE cardiac xenografts have variable cardiac xenograft survival in NHP due to perhaps presence of 4th antigen and require further study. However, these 10GE organs may be suitable for clinical cardiac xenotransplantation and have already been utilized in two human cases., Competing Interests: Competing interests: All other authors except K.K. and D.A. declare no competing interests or personal relationships that could have appeared to influence the work reported in this article. K.K. and D.A. are employees of Revivicor Inc., Blacksburg, VA, USA, and got a salary, as part of the data acquisition for this study but their role could not have appeared to influence the work reported in this article., (© 2025. The Author(s).)