Long-term follow-up after Bentall operation using a stentless Shelhigh NR-2000 bio-conduit.

BACKGROUND: To analyze the long-term results after Bentall operation using the stentless Shelhigh No-React (NR)-2000 bio-root prosthesis. MATERIAL: From 2004 to 2008, 26 consecutive, nonselected patients (mean age at surgery: 67 ± 9 years) underwent a Bentall operation using a stentless Shelhigh valved conduit at our institution. Mean preoperative Logistic-EuroSCORE was 17.1 ± 12.9. The mean size of the aortic root was 53.2 ± 5 mm. The mean preoperative ejection fraction was 55 ± 7.4%. Three patients had a bicuspid valve. One patient with acute endocarditis and one patient with type A aortic dissection were operated on an emergency. Three patients (11.54%) had a previous cardiac operation. The Button-Bentall technique was used in all cases. Seven patients (26.92%) received an associated procedure. The mean size of the implanted prosthesis was 26.1 ± 2.2. Follow-up ranged between 6 and 174 months (mean 93.4 ± 59.1 months). Primary endpoints consisted of early and late mortality, freedom from acute endocarditis, freedom from structural valve deterioration, and freedom from valve-related-reoperation. RESULTS: Two patients died in hospital, while 10 patients died during follow-up time, of which three for cardiac causes (12.5%). Overall survival probability was 52.9% at 15 years. Freedom from acute endocarditis was 95.7% at 5 and 15 years. Freedom from severe aortic incompetence due to structural deterioration was 100% at 5 and 10 years, 90.9% at 15 years. The mean aortic gradient at follow-up was 11.4 ± 5 mm Hg. Freedom from valve-related reoperation was 100% at 5 and 10 years, 90.9% at 15 years. CONCLUSIONS: In our experience, Bentall's operation using the Shelhigh NR-2000 stentless bio-conduit provided satisfactory early and long-term results. However, our findings are not consistent with unfavorable long-term outcomes following the implantation of this device reported by other authors.

Repair of colonic neovaginal stenosis using a biological graft in a male-to-female transgender patient.

INTRODUCTION AND HYPOTHESIS: One in 2900 genotypical men report gender dysphoria, and many undergo gender confirmation surgery to match their physical phenotype to their identity. A variety of surgical techniques are used in male-to-female transgender patients, one of which is bowel vaginoplasty, and postoperative stenosis of the colonic neovagina is common. Extracellular matrix grafts have been used in vaginal reconstruction. with porcine urinary bladder matrix (UBM) acting as a scaffold for smooth-muscle tissue and matrix regeneration. The aim of this surgical video is to describe the use of a UBM biological graft in repair of introital stenosis due to recurrent granulation tissue in the colonic neovagina of a male-to-female transgender patient. METHODS: A 32-year-old male-to-female transgender patient with a history of rectosigmoid neovagina formation for genital gender confirmation surgery 12 months prior presented with genital granulation tissue and stenosis of her neovaginal introitus. Despite two surgical revisions, the patient developed recurrence of granulation tissue and obliteration of the neovaginal introitus, preventing sexual function of the neovagina. RESULTS: Reconstruction of the neovaginal introitus was performed using UBM. The patient noted improvement in comfort, hygiene, and quality of life following the procedure. This video describes our surgical technique and perioperative clinical findings. CONCLUSIONS: We report the novel use of UBM biological graft in the revision of a neovaginal introitus after former rectosigmoid vaginoplasty in a male-to-female transgender patient.

[Reaction of connective tissue of arterial and venous walls to implantation of synthetic and biological grafts]. / Reaktsiia soedinitel'noi tkani arterial'noi i venoznoi stenok na implantatsiiu sinteticheskogo i biologicheskogo protezov.

BACKGROUND: 30% of patients in the remote period appear to develop restenosis of the anastomoses formed during reconstructive-restorative operations on vessels. Two major causes of restenosis have been determined: intimal hyperplasia and smooth muscle cell proliferation. The reaction of connective-tissue elements of vascular walls in response to implantation of grafts remains unstudied. OBJECTIVE: The study was undertaken to examine the reaction of connective tissue of the arterial and venous walls to implantation of synthetic and biological grafts. MATERIAL AND METHODS: We analysed the results of an experimental study performed on a total of 60 rabbits divided into 4 groups each consisting of 15 animals: in the first 2 groups we examined tissue reaction to implantation of synthetic and biological grafts on the wall of an artery and in the remaining 2 groups - on the wall of a vein. The synthetic grafts were made of polytetrafluoroethylene, with the biological ones made of bovine internal thoracic arteries. The portions of the vessels along with the implanted grafts were subjected to histological examination on postoperative days 14, 21 and 30. The specimens were studied by means of light microscopy after haematoxylin-eosin staining. We also carried out a morphometric study consisting in determining the quantitative ratio of the cellular composition of connective tissue. RESULTS: After implantation on the arterial wall, the connective-tissue capsule under the synthetic prosthesis was 1.8 times thicker than under the biological one, with predominance of the cellular component over fibrous one, which deformed the zone of implantation. Under the biological prosthesis, the capsule on the arterial wall was presented by fibrous structures with no deformation of the zone of implantation. The reparative reaction of the venous wall to implantation of the synthetic prosthesis was represented by a thin fibrous connective-tissue capsule. The reaction of the venous wall to the biological transplant was at all terms of the experiment characterised by significant inflammatory alterations with granulomatosis and immunomorphological shifts with formation of lymphoid follicles on the border with the transplant. CONCLUSION: Implantation of the synthetic polytetrafluoroethylene prosthesis on the arterial wall induced a hyperplastic reaction of the elements of connective tissue, and a normoplasic one on the venous wall. Implantation of the biological prosthesis on the arterial wall did not induce proliferation of connective-tissue elements, and on the venous wall - granulomatous inflammation.

Histological and Mechanical Assessment of Decellularized Porcine Biografts, and Its Biological Evaluation following Aortic Implantation during Mid-Term Follow-Up.

AIMS: Prosthetic graft infection frequently requires graft replacement. Among other options, a biological graft could serve as an alternative choice. Decellularization reduces tissue immunogenicity. Our aim was to determine an efficient decellularization method and to evaluate the decellularized porcine biografts' adaptability. METHODS: Four different protocols were implemented to decellularize porcine aortic segments (n = 4). Cell removal effectiveness and matrix structure preservation were histologically examined. Mechanical tests were performed. Decellularized porcine grafts were interpositioned in a porcine aorta. After a 6-month period, implanted samples were removed and evaluated using light and electron microscopy. RESULTS: Histological results showed complete removal of cells and preserved connective tissue fiber structure following decellularization, using sodium dodecyl sulfate and sodium azide. Pressure tests demonstrated similar compliance to fresh vessels. In 9 out of 10 cases, pigs survived the follow-up period. Graft rejection, intimal hyperplasia, reocclusion and/or aneurysm formation were not observed. Presence of host cells and neoendothelialization were microscopically confirmed. CONCLUSIONS: This decellularization protocol enables a cost-effective preparation of biological grafts featuring reduced immunogenicity. The implanted grafts did not degenerate during the 6-month follow-up period, the lack of graft rejection suggests acceptable immunological tolerance, while recipient cells migrate into, proliferate and differentiate, thus creating the possibility for further use as an optional vascular graft.

Transverse incision transvaginal rectocele repair combined with levatorplasty and biological graft insertion: technical details and case series outcomes.

BACKGROUND: The purpose of this report is twofold: first, to detail our operative approach to rectocele repair, and second, to report on the outcomes. METHODS: Transverse incision transvaginal rectocele repair combined with levatorplasty and biological graft placement is detailed using hand-drawn sketches and intraoperative photographs. All patients with symptoms of functional constipation and non-emptying rectocele operated on from May 2007 to March 2013 at our institution were enrolled in this study. Data from a prospectively maintained database were retrospectively analyzed. Preoperative and postoperative functional outcomes were studied using a validated 31-point obstructed defecation (OD) scoring system. Follow-up was 1 year. RESULTS: Twenty-three patients underwent the procedure. The mean age of patients was 55 years (range 28-79 years). The OD severity score improved from the preoperative mean of 21.6 to postoperative mean of 5.5 (p = 0.001). Three out of four patients with initial symptoms of dyspareunia (75%) reported significant improvement in dyspareunia, while 2 out of 19 patients without initial symptoms of dyspareunia (11%) reported mild dyspareunia following the repair. One patient (4%) required operative drainage of a hematoma. Another patient (4%) developed symptomatic recurrence which was confirmed radiologically. CONCLUSIONS: In properly selected patients, the technique described leads to significant improvement in symptoms of OD and low recurrence without an increased rate of dyspareunia.

Use of a bioprosthetic mesh in complex hernia repair: early results from a French multicenter pilot study.

BACKGROUND: Implantation of synthetic meshes for reinforcement of abdominal wall hernias can be complicated by mesh infection, which often requires mesh explantation. The risk of mesh infection is increased in a contaminated environment or in patients who have comorbidities such as diabetes or smoking. The use of biological prostheses has been advocated because of their ability to resist infection. Initial results, however, have shown high hernia recurrence rates and wound occurrences. The objective of the present study is to evaluate early and mid-term outcomes in the largest French series that included 43 consecutive complex abdominal hernias repaired with biological prostheses. MATERIALS AND METHODS: Retrospective observational study of a prospective collected data bank. Patient demographics, history of previous repairs, intraoperative findings and degree of contamination, associated procedures, postoperative prosthetic-related complications, and long-term results were retrospectively reviewed. RESULTS: There were 25 (58%) incisional, 14 parastomal, and 4 midline hernia repairs. Hernias were considered "clean" (n = 5), "clean-contaminated" (n = 19), "contaminated" (n = 12), or "dirty" (n = 7). Wound-related morbidity occurred in 17 patients; 4 patients needed reoperation for cutaneous necrosis or abscess. Smoking was the only risk factor associated with wound complication (P = .022). No postoperative wound events required removal of the prosthesis. There were 4 hernia recurrences (9%). A previous attempt at repair (P = .018) and no complete fascia closure (P = .033) were associated with hernia recurrence. CONCLUSIONS: This study demonstrated that the use of bioprothesis in complex hernia repair allowed successful single-stage reconstruction. Wound-related complications were frequent. Cost-benefit analyses are important to establish the validity of these findings.

In-vivo evaluation of silk fibroin small-diameter vascular grafts: state of art of preclinical studies and animal models.

Autologous vein and artery remains the first choice for vascular grafting procedures in small-diameter vessels such as coronary and lower limb districts. Unfortunately, these vessels are often found to be unsuitable in atherosclerotic patients due to the presence of calcifications or to insufficient size. Synthetic grafts composed of materials such as expanded polytetrafluoroethylene (ePTFE) are frequently employed as second choice, because of their widespread availability and success in the reconstruction of larger arteries. However, ePTFE grafts with small diameter are plagued by poor patency rates due to surface thrombogenicity and intimal hyperplasia, caused by the bioinertness of the synthetic material and aggravated by low flow conditions. Several bioresorbable and biodegradable polymers have been developed and tested to exploit such issues for their potential stimulation to endothelialization and cell infiltration. Among these, silk fibroin (SF) has shown promising pre-clinical results as material for small-diameter vascular grafts (SDVGs) because of its favorable mechanical and biological properties. A putative advantage in graft infection in comparison with synthetic materials is plausible, although it remains to be demonstrated. Our literature review will focus on the performance of SF-SDVGs in vivo, as evaluated by studies performing vascular anastomosis and interposition procedures, within small and large animal models and different arterial districts. Efficiency under conditions that more accurately mime the human body will provide encouraging evidence towards future clinical applications.

Comparing Anatomical and Functional Outcomes of Two Neovaginoplasty Techniques for Mayer-Rokitansky-Küster-Hauser Syndrome: A Ten-Year Retrospective Study with Swine Small Intestinal Submucosa and Homologous Skin Grafts.

Objective: This study aimed to compare the anatomical and functional outcomes of the modified McIndoe vaginoplasty for Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome using swine small intestinal submucosa (SIS) graft or homologous skin grafts. Methods: A total of 115 patients with MRKHs who underwent neovaginoplasty between January 2012 and December 2021 were included in the study. Among them, 84 patients received vaginal reconstruction with SIS graft, whereas 31 neovaginoplasty underwent a skin graft procedure. The length and width of the neovagina were measured, and sexual satisfaction was evaluated using the Female Sexual Function Index (FSFI). The operation details, cost, and complications were also assessed. Results: The SIS graft group had a significantly shorter mean operation time (61.13±7.17min) and less bleeding during the operation (38.57±9.46mL) compared to the skin graft group (92.1±9.47min and 55.81±8.28mL, respectively). The mean length and width of the neovagina in the SIS group were comparable to the skin graft group at 6 months follow-up (7.73±0.57 cm versus 7.6±0.62cm, P=0.32). The SIS group had a higher total FSFI index than the skin graft group (27.44±1.58 versus 25.33±2.16, P=0.001). Conclusion: The modified McIndoe neovaginoplasty using SIS graft is a safe and effective alternative to homologous skin grafts. It results in comparable anatomical outcomes and superior sexual and functional outcomes. Overall, these results suggest that the modified McIndoe neovaginoplasty using SIS graft is preferred for MRKH patients who require vaginal reconstruction.

Capnocytophaga canimorsus Mycotic Aortic Aneurysm After a Dog Bite.

Introduction: Mycotic aortic aneurysm is defined as dilatation of the aortic wall due to infection caused by a variety of microorganisms and is associated with high mortality rates. This case report describes a patient with a rapid growing mycotic infrarenal aneurysm caused by Capnocytophaga canimorsus following a dog bite. Report: A 61 year old male professional dog handler presented with a history of progressive abdominal pain and constitutional symptoms. He had been bitten by a Pit Bull Terrier dog that was attacking a young girl three weeks prior to the onset of complaints. Investigations revealed a mycotic infrarenal aortic aneurysm that grew 0.5 cm in only three days. Open surgical repair consisting of an infrarenal aorto-aortic bypass with a 21 mm × 15 cm bovine bioprosthesis was performed successfully. All cultures and biopsies were negative and the subsequent 16S-23S rRNA intergenic spacer region based polymerase chain reaction (IS-pro) technique revealed C. canimorsus, a Gram negative bacterial pathogen that lives as a commensal in the gingival flora of dogs and cats that can cause a variety of severe infections, as the causative agent. Identification made it possible to treat the patient with eight weeks of intravenous followed by four weeks of oral antibiotics. At the last follow up over a year after surgery, the patient was symptom free, without infection and on ultrasound examination there were no signs of complications or aneurysm formation. Discussion: This case highlights C. canimorsus as a rare cause of a rapid growing mycotic aortic aneurysm following a dog bite. 16S-23S rRNA profiling (IS-pro) led to the identification of the bacterial pathogen. The use of biological grafts should be considered in the management of mycotic aortic aneurysms.

Cross-linked xenogenic collagen implantation in the sheep model for vaginal surgery.

The properties of meshes used in reconstructive surgery affect the host response and biomechanical characteristics of the grafted tissue. Whereas durable synthetics induce a chronic inflammation, biological grafts are usually considered as more biocompatible. The location of implantation is another determinant of the host response: the vagina is a different environment with specific function and anatomy. Herein, we evaluated a cross-linked acellular collagen matrix (ACM), pretreated by the anti-calcification procedure ADAPT® in a sheep model for vaginal surgery. Ten sheep were implanted with a cross-linked ACM, and six controls were implanted with a polypropylene (PP; 56 g/m2) control. One implant was inserted in the lower rectovaginal septum, and one was used for abdominal wall defect reconstruction. Grafts were removed after 180 days; all graft-related complications were recorded, and explants underwent bi-axial tensiometry and contractility testing. Half of ACM-implanted animals had palpable induration in the vaginal implantation area, two of these also on the abdominal implant. One animal had a vaginal exposure. Vaginal ACMs were 63 % less stiff compared to abdominal ACM explants (p = 0.01) but comparable to vaginal PP explants. Seven anterior vaginal ACM explants showed areas of graft degradation on histology. There was no overall difference in vaginal contractility. Considering histologic degradation in the anterior vaginal implant as representative for the host, posterior ACM explants of animals with degradation had a 60 % reduced contractility as compared to PP (p = 0.048). Three abdominal implants showed histologic degradation; those were more compliant than non-degraded implants. Vaginal implantation with ACM was associated with graft-related complications (GRCs) and biomechanical properties comparable to PP. Partially degraded ACM had a decreased vaginal contractility.

Mesh for prolapse surgery: Why the fuss?

Pelvic organ prolapse is a common gynaecological problem. Surgical techniques to repair prolapse have been constantly evolving to reduce the recurrence of prolapse and need for reoperation. Grafts made of synthetic and biological materials became popular in the last decade as they were intended to provide extra support to native tissue repairs. However, serious complications related to use of synthetic meshes have been reported and there is increasing medico-legal concern about mesh use in prolapse surgery. Some mesh products already have been withdrawn from the market and the FDA has introduced stricter surveillance of new and existing products. Large randomized studies comparing mesh with non-mesh procedures are lacking which creates uncertainty for the surgeon and their patients.The small cohorts of the RCTs available with short follow-up periods just allow the conclusion that the mesh repair can be helpful in the short to medium term but unfortunately are not able to prove safety for all patients. In particular, current clinical reports cannot define for which indication what material may be superior compared to non-mesh repair.Quality control through long-term individual and national mesh registries is needed to keep a record of all surgeons using mesh and all devices being used, monitoring their effectiveness and safety data. Meshes with better biocompatibility designed specifically for use in vaginal surgery may provide superior clinical results, where the reduction of complications may allow a wider range of indications.

Biomechanical behavior of pericardial human tissue: a constitutive formulation.

This work aims to present a constitutive model suitable to interpret the biomechanical response of human pericardial tissues. The model is consistent with the need of describing large strains, anisotropy, almost incompressibility, and time-dependent effects. Attention is given to human pericardial tissue because of the increased interest in its application as a substitute in reconstructive surgery. Specific, even limited, experimental investigation has been performed on human samples taken from surgical grafts in order to verify the capability of the constitutive model in supplying a correct description of tissue mechanical response. Experimental data include uni-axial tensile tests and stress relaxation tests up to 300 s, developed along different directions of the tissue. The grafts tested show different mechanical characteristics for what concern the level of anisotropy of the tissue. The constitutive model proposed shows to adapt to the different configurations of the human pericardium grafts, as emerged by experimental data considered, and it is capable to describe the variability of the mechanical characteristics.

Verification of small intestinal submucosa graft stent in vitro / 国际生物医学工程杂志

Objective To verify the feasibility of using small intestine submucosa for graft stents.Methods A Z-type Nitinol wire stent was used as the metal stent material,and porcine small intestine submucosa was used as the biofilm material to prepare the bio-coated stent.In vitro implantation,extracorporeal pulsation and extracorporeal flexion of the stents were designed based on the requirements for the small intestine submucosa graft stent implantation during the endovascular aneurysm repair and of the mechanical properties of the graft stent during human body activity.The feasibility of using small intestine submucosa for the graft stents was evaluated according to the patency of the stent lumen after the experiment,the presence or absence of cracks in the membrane,and the presence or absence of fracture of the metal stent.Results In the in vitro experiments,all the samples were able to maintain complete tunica and luminal patency except the 8th sample that showed suture rupture.Besides,all the samples showed good rebounding and adhering properties in both in vitro implantations and extracorporeal pulsation pressure experiments,and no dangerous problems were found such as film rupture,suture loss and stent fracture.Conclusion Small intestine submucosa can meet the durability requirements of graft stents,adapt to the conditions of graft stents such as implantation,bending and blood pulsation,and can be used as the covering material of graft stents.