The occurrence of acute kidney injury (AKI) following aortic valve replacement (AVR) has very serious clinical implications and has therefore been the focus of several studies. The authors report the results of previous studies evaluating both transcatheter AVR (TAVR) and indirectly surgical AVR (SAVR) through looking at cardiopulmonary bypass (CPB) cardiac surgeries, and identify the incidence, predictors and outcomes of AKI following AVR. In most studies, AKI was defined using the Risk, Injury, Failure, Loss and End Stage, Valve Academic Research Consortium (modified Risk, Injury, Failure, Loss and End Stage) or Valve Academic Research Consortium-2 (Acute Kidney Injury Network) AKI classification criteria. Twelve studies including more than 90,000 patients undergoing cardiac surgery on CPB were considered as well as 26 studies with more than 6000 patients undergoing TAVR. Depending on the definition used, AKI occurred in 3.4-43% of SAVR cases with up to 2.5% requiring dialysis, and in 3.4-57% of TAVR cases. Factors identified as independent predictors of AKI were: baseline kidney failure, EUROSCORE, diabetes mellitus, hypertension, chronic obstructive pulmonary disease, anemia, peripheral vascular disease, heart failure, surgical priority, CPB time, reoperation, use of intra-aortic balloon pump, need for re-exploration, contrast agent volume, transapical access, blood transfusion, postoperative thrombocytopenia, postoperative leukocytosis as well as demographic variables such as age and female gender. The 30-day mortality rate for patients with AKI following SAVR ranged from 5.5 to 46% and was 3- to 16-times higher than in those without AKI. Similarly, patients who developed AKI after TAVR had a mortality rate of 7.8-29%, which was two- to eight-times higher than those who did not suffer from AKI. AKI confers up to a fourfold increase in 1-year mortality. Finally, hospital length of stay was significantly increased in patients with AKI in both SAVR and TAVR groups, with increases up to 3- and 2.5-times, respectively.

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Tracheal reconstruction is indicated in cases of malignancy, traumatic injury, and subglottic or tracheal stenosis. Recent progress in airway transplantation has provided renewed optimism for potential solutions for defects involving more than half of the tracheal length in adults or one-third of the tracheal length in children. Biologic scaffolds derived from decellularized tissues and organs have shown great promise in tracheal allotransplantation, and cyclical decellularization techniques have been hypothesized as abrogating the need for immunosuppressive therapy. In this study, we performed a direct comparison of three decellularization protocols (Protocols A, B, and C) previously described in the literature, two of which were described in tracheal tissue (Protocols A and B). We concentrated on the immunogenicity within the epithelium and mucosa, quantified and qualified the extracellular matrix (ECM) components, and performed compliance measurements on large circumferential decellularized tracheal scaffolds following cyclical decellularization techniques using all three protocols. Quantitative measurements of glycosaminoglycans (GAGs) showed a significant decrease in the mucosal component following 17 cycles of all 3 protocols as well as a significant decrease of GAGs in the cartilaginous component following cycles 1, 9, and 17 of Protocol A and cycle 17 of Protocol C. Compliance measurements were also shown to be different between the protocols, with grafts becoming more compliant at physiologic pressures after cyclical decellularization with Protocols A and B and slightly less compliant but remaining similar to native trachea using Protocol C. Positive staining for anti-major histocompatibility complex Class I (anti-MHCI) and anti-MHCII remained within the submucosal glandular components despite multiple cycles of decellularization using all three protocols. This study illustrated that there are significant differences in ECM composition and resultant structural integrity of decellularized tracheal scaffolds depending on the decellularization protocol. Protocol B was shown to maintain the GAGs components despite an increase in tracheal compliance, while Protocol C decreases GAGs components following multiple cycles, despite showing a tracheal compliance resembling that of the native trachea at physiologic airway pressures.

Background Cardiogenic shock ( CS ) following acute myocardial infarction ( AMI ) portends a poor prognosis. Both venoarterial extracorporeal membrane oxygenation ( VA ‐ ECMO ) and a percutaneous ventricular assist device ( pVAD ) provide hemodynamic support for patients with CS, but little is known about the best device for this population. We sought to compare outcomes of AMI patients treated with these devices. Methods and Results Consecutive patients with CS following AMI from April 2015 to March 2017 were enrolled prospectively if they received either device for AMI ‐related CS . If patients received both devices, they were analyzed according to the first used. The primary outcome was all‐cause mortality. In total, 51 patients received VA ‐ ECMO or pVAD following AMI ; 20 received VA ‐ ECMO, and 31 received pVAD . The mean age was 62.1±10.1 years, and 39 (76.5%) were men. Twenty‐four (47.1%) patients were ultimately supported by both devices simultaneously (20 pVAD ‐first, 4 VA ‐ ECMO ‐first). Patients treated with pVAD or VA ‐ ECMO were similar in baseline characteristics at initial device insertion except that the latter were on more vasopressors and were more likely to have an intra‐aortic balloon pump. Seventeen (33.3%) had recent cardiopulmonary resuscitation, mean lactate was 4.86±3.96 mmol/L, and mean cardiac index was 1.70±0.42 L/min per m 2 . Of the 28 (54.9%) patients surviving to discharge, 11 had received VA ‐ ECMO first and 17 had pVAD first ( P =0.99). Survival at 1 and 2 years did not differ significantly between device groups ( P =0.42). Conclusions Following AMI ‐related CS , pVAD ‐ and VA ‐ ECMO ‐treated patients had similar outcomes. The use of both devices simultaneously was common, with almost half of patients in persistent CS after first device deployment.

The number of available donor organs limits lung transplantation, the only lifesaving therapy for the increasing population of patients with end-stage lung disease. A prevalent etiology of injury that renders lungs unacceptable for transplantation is gastric aspiration, a deleterious insult to the pulmonary epithelium. Currently, severely damaged donor lungs cannot be salvaged with existing devices or methods. Here we report the regeneration of severely damaged lungs repaired to meet transplantation criteria by utilizing an interventional cross-circulation platform in a clinically relevant swine model of gastric aspiration injury. Enabled by cross-circulation with a living swine, prolonged extracorporeal support of damaged lungs results in significant improvements in lung function, cellular regeneration, and the development of diagnostic tools for non-invasive organ evaluation and repair. We therefore propose that the use of an interventional cross-circulation platform could enable recovery of otherwise unsalvageable lungs and thus expand the donor organ pool.

Summary:A recent revival of global interest for reconstruction of long-segment tracheal defects, which represents one of the most interesting and complex problems in head and neck and thoracic reconstructive surgery, has been witnessed. The trachea functions as a conduit for air, and its subunits including the epithelial layer, hyaline cartilage, and segmental blood supply make it particularly challenging to reconstruct. A myriad of attempts at replacing the trachea have been described. These along with the anatomy, indications, and approaches including microsurgical tracheal reconstruction will be reviewed. Novel techniques such as tissue-engineering approaches will also be discussed. Multiple attempts at replacing the trachea with synthetic scaffolds have been met with failure. The main lesson learned from such failures is that the trachea must not be treated as a “simple tube.” Understanding the anatomy, developmental biology, physiology, and diseases affecting the trachea are required for solving this problem.

Background: The onset of the coronavirus disease 2019 (COVID-19) pandemic has forced our cardiac surgery program and hospital to enact drastic measures that has forced us to change how we care for cardiac surgery patients, assist with COVID-19 care, and enable support for the hospital in terms of physical resources, providers, and resident training. Methods: In this review, we review the cardiovascular manifestations of COVID-19 and describe our system-wide adaptations to the pandemic, including the use of telemedicine, how a severe reduction in operative volume affected our program, the process of redeployment of staff, repurposing of residents into specific task teams, the creation of operation room intensive care units, and the challenges that we faced in this process. Results: We offer a revised set of definitions of surgical priority during this pandemic and how this was applied to our system, followed by specific considerations in coronary/valve, aortic, heart failure and transplant surgery. Finally, we outline a path forward for cardiac surgery for the near future. Conclusions: We recognize that individual programs around the world will eventually face COVID-19 with varying levels of infection burden and different resources, and we hope this document can assist programs to plan for the future.

Tracheal transplantation with a long-segment recellularized tracheal allograft has previously been performed without the need for immunosuppressive therapy. Recipients' mesenchymal stromal cells (MSC) and tracheal epithelial cells (TEC) were harvested, cultured, expanded, and seeded on a donor trachea within a bioreactor. Prior techniques used for cellular seeding have involved only static-seeding methods. Here, we describe a novel bioreactor for recellularization of long-segment tracheae. Tracheae were recellularized with epithelial cells on the luminal surface and bone marrow-derived MSC on the external surface. We used dynamic perfusion seeding for both cell types and demonstrate an increase in both cellular counts and homogeneity scores compared with traditional methods. Despite these improvements, orthotopic transplantation of these scaffolds revealed no labeled cells at postoperative day 3 and lack of re-epithelialization within the first 2 weeks. The animals in this study had postoperative respiratory distress and tracheal collapse that was incompatible with life.