A robotic implant for inducing tissue growth in tubular organs is demonstrated through esophageal lengthening in swine.

Structural cardiac lesions are often surgically repaired using prosthetic patches, which can be biological or synthetic. In the current clinical scenario, biological patches derived from the decellularization of a xenogeneic scaffold are gaining more interest as they maintain the natural architecture of the extracellular matrix (ECM) after the removal of the native cells and remnants. Once implanted in the host, these patches can induce tissue regeneration and repair, encouraging angiogenesis, migration, proliferation, and host cell differentiation. Lastly, decellularized xenogeneic patches undergo cell repopulation, thus reducing host immuno-mediated response against the graft and preventing device failure. Porcine small intestinal submucosa (pSIS) showed such properties in alternative clinical scenarios. Specifically, the US FDA approved its use in humans for urogenital procedures such as hernia repair, cystoplasties, ureteral reconstructions, stress incontinence, Peyronie’s disease, penile chordee, and even urethral reconstruction for hypospadias and strictures. In addition, it has also been successfully used for skeletal muscle tissue reconstruction in young patients. However, for cardiovascular applications, the results are controversial. In this study, we aimed to validate our decellularization protocol for SIS, which is based on the use of Tergitol 15 S 9, by comparing it to our previous and efficient method (Triton X 100), which is not more available in the market. For both treatments, we evaluated the preservation of the ECM ultrastructure, biomechanical features, biocompatibility, and final bioinductive capabilities. The overall analysis shows that the SIS tissue is macroscopically distinguishable into two regions, one smooth and one wrinkle, equivalent to the ultrastructure and biochemical and proteomic profile. Furthermore, Tergitol 15 S 9 treatment does not modify tissue biomechanics, resulting in comparable to the native one and confirming the superior preservation of the collagen fibers. In summary, the present study showed that the SIS decellularized with Tergitol 15 S 9 guarantees higher performances, compared to the Triton X 100 method, in all the explored fields and for both SIS regions: smooth and wrinkle.

The aim of this study was to evaluate short- and long-term clinical outcomes, including the perceived health-related quality of life, in patients younger than 65 years having undergone aortic valve replacement either with biological or mechanical valve prostheses. Between 2002 and 2013, 242 consecutive patients <65 years of age underwent isolated aortic valve replacement at our institution, either with biological (n = 134, 55.4%) or mechanical (n = 108, 44.6%) prostheses. Survival, health-related quality of life, short- and long-term clinical outcomes and echocardiographic data were analysed with a retrospective, single-centre study. Propensity matching was performed. No significant difference in survival was found between the 2 groups (mechanical versus biological: 100% vs 96.6% at 1 year, 98.2% vs 93.1% at 5 years and 92.3% vs 83.4% at 10 years after surgery, P = 0.091). For all the interviewed patients (n = 161, 66.5%), perceived quality of life at the latest follow-up was excellent. Need for reoperation was higher in the bioprosthetic group (8% vs 0%, P = 0.995), whereas the rate of major bleedings was higher in the mechanical valve group (3% vs 20%, P = 0.094). The mean and maximum transvalvular pressure gradients were 20.5 ± 9.7 and 37.4 ± 17.5 mmHg in the biological group and 14.8 ± 4.8 and 26.6 ± 9.2 mmHg in the mechanical group (P = 0.014). No significant differences were found between biological and mechanical valves in terms of patients’ survival, clinical outcomes and quality of life. Mean and maximum transvalvular pressure gradients were significantly higher in the biological group. The majority of patients would opt for the same prosthesis type, if asked to choose again.

The most common aortic valve diseases in adults are stenosis due to calcification and regurgitation. In pediatric patients, aortic pathologies are less common. When a native valve is surgically replaced by a prosthetic one, it is necessary to consider that the latter has a limited durability. In particular, current bioprosthetic valves have to be replaced after approximately 10 years; mechanical prostheses are more durable but require the administration of permanent anticoagulant therapy. With regard to pediatric patients, both mechanical and biological prosthetic valves have to be replaced due to their inability to follow patients’ growth. An alternative surgical substitute can be represented by the acellular porcine aortic valve that exhibits less immunogenic risk and a longer lifespan. In the present study, an efficient protocol for the removal of cells by using detergents, enzyme inhibitors, and hyper- and hypotonic shocks is reported. A new detergent (Tergitol) was applied to replace TX-100 with the aim to reduce toxicity and maximize ECM preservation. The structural integrity and efficient removal of cells and nuclear components were assessed by means of histology, immunofluorescence, and protein quantification; biomechanical properties were also checked by tensile tests. After decellularization, the acellular scaffold was sterilized with a standard protocol and repopulated with bone marrow mesenchymal stem cells to analyze its biocompatibility profile.

Right ventricle outflow tract obstruction (RVOTO) is a congenital pathological condition that contributes to about 15% of congenital heart diseases. In most cases, the replacement of the right ventricle outflow in pediatric age requires subsequent pulmonary valve replacement in adulthood. The aim of this study was to investigate the extracellular matrix scaffold obtained by decellularization of the porcine pulmonary valve using a new detergent (Tergitol) instead of Triton X-100. The decellularized scaffold was evaluated for the integrity of its extracellular matrix (ECM) structure by testing for its biochemical and mechanical properties, and the cytotoxicity/cytocompatibility of decellularized tissue was assessed using bone marrow-derived mesenchymal stem cells. We concluded that Tergitol could remove the nuclear material efficiently while preserving the structural proteins of the matrix, but without an efficient removal of the alpha-gal antigenic epitope. Therefore, Tergitol can be used as an alternative detergent to replace the Triton X-100.