Urinary Bladder Matrix Scaffolds Promote Pericardium Repair in a Porcine Model.

Pericardium closure after cardiac surgery is recommended to prevent postoperative adhesions to the sternum. Synthetic materials have been used as substitutes, with limited results because of impaired remodeling and fibrotic tissue formation. Urinary bladder matrix (UBM) scaffolds promote constructive remodeling that more closely resemble the native tissue. The aim of the study is to evaluate the host response to UBM scaffolds in a porcine model of partial pericardial resection. Twelve Landrace pigs were subjected to a median sternotomy. A 5 × 7 cm pericardial defect was created and then closed with a 5 × 7 cm multilayer UBM patch (UBM group) or left as an open defect (control group). Animals were survived for 8 wk. End points included gross morphology, biomechanical testing, histology with semiquantitative score, and cardiac function. The UBM group showed mild adhesions, whereas the control group showed fibrosis at the repair site, with robust adhesions and injury to the coronary bed. Load at failure (gr) and stiffness (gr/mm) were lower in the UBM group compared with the native pericardium (199.9 ± 59.2 versus 405.3 ± 99.89 g, P = 0.0536 and 44.23 ± 15.01 versus 146.5 ± 24.38 g/mm, P = 0.0025, respectively). In the UBM group, the histology resembled native pericardial tissue, with neovascularization, neofibroblasts, and little inflammatory signs. In contrast, control group showed fibrotic tissue with mononuclear infiltrates and a lack of organized collagen fibers validated with a histologic score. Both groups had normal ultrasonography results without cardiac motility disorders. In this setting, UBM scaffolds showed appropriate features for pericardial repair, restoring tissue properties that could help reduce postsurgical adhesions and prevent its associated complications.

Biomechanical Features of Reinforced Esophageal Hiatus Repair in a Porcine Model.

Recurrence rates in the laparoscopic repair of the hiatal hernia range from 12% to 59%. Limitation of reinforcement has been principally the risk of adverse events caused by synthetic materials. Biologic and resorbable synthetic materials are valid alternatives. This study compares the host response to all these materials after hiatal hernia repair. A total of 20 Landrace pigs, underwent laparoscopic primary hiatal hernia repair and reinforced with a polypropylene mesh (PROLENE: polypropylene [PP]), an absorbable synthetic scaffold (GOREBIO-A: polyglycolic acid [PGA]), a urinary bladder matrix scaffold, (Gentrix: urinary bladder matrix [UBM]), or without reinforcement, control group (C). Animals were survived for 3 months. Endpoints included gross morphology, biomechanical testing, and histology. Pigs in PP and PGA groups showed fibrosis at the repair site, with robust adhesions. In UBM and C groups, only mild adhesions were found. Load at failure (gr) and stiffness (gr/mm) of PP were higher than C group (PP:2103 ± 548.3 versus C:951.1 ± 372.7, P = 0.02; PP:643.3 ± 301 versus C:152.6 ± 142.7, P = 0.01). PGA and UBM values for both parameters were in between PP and C samples. However, stiffness in UBM was tended to be lower than PP group, and approached a significant difference (643.3 ± 301 versus 243 ± 122.1, P = 0.0536). In UBM group, the histology resembled native tissue. By contrast, PP and PGA groups showed mononuclear infiltrates, fibroencapsulation, necrosis, remnants of mesh, and disorganized tissue that was validated with a histologic score. In this setting, UBM scaffolds showed the most appropriate features for hiatal hernia repair, recovering the tissue properties that can help reduce the possibility of early failure and prevent complications associated with the implanted material.

Urinary bladder matrix scaffolds strengthen esophageal hiatus repair.

BACKGROUND: Laparoscopic repair of the hiatal hernia is associated with a recurrence rate between 12% and 42% depending on the defect size. Although the impact of hiatal reinforcement on long-term recurrence remains controversial, the main limitation of this approach has been the risk of adverse events related with the use of synthetic materials in the vicinity of the esophagus. METHODS: A total of 14 female domestic pigs underwent laparoscopic primary hiatal hernia repair of a simulated defect in the esophageal hiatus. Seven of the hiatal repairs were reinforced with an extracellular matrix (ECM) scaffold, whereas the remaining seven served as primary repair controls. Animals were survived for 8 wk. At necropsy, after gross morphologic evaluation, samples were sent for mechanical testing and histology. RESULTS: The repaired defect site reinforced with ECM scaffolds showed a robust closure of the crura in all cases with a smooth peritoneal-like structure covering the entire repair. Average load at failure of the treated group was found to be significantly stronger than that of the controls (185.8 ± 149.7 g versus 57.5 ± 57.5 g, P < 0.05). Similarly, the stiffness was significantly higher in the treated animals (57.5 ± 26.9 g/mm versus 19.1 ± 17.5 g/mm; P < 0.01). Interestingly, there was no difference in elongation at failure (7.62 ± 2.02 mm versus 7.87 ± 3.28 mm; P = 0.44). CONCLUSIONS: In our animal survival model, we have provided evidence that the addition of an ECM to augment a primary hiatal repair leads to tissue characteristics that may decrease the possibility of early failure of the repair. This may translate to decreased recurrence rates. Further study is necessary.

[Radiofrequency ablation for Barrett's esophagus. Preliminary experience]. / Ablación por radiofrecuencia en esófago de Barrett. Experiencia Inicial.

UNLABELLED: Endoscopic radiofrequency ablation makes use of warm energy to ablate the esophagus's surface where the epithelial anomaly is located. PATIENTS AND METHODS: 50 adults patients with the diagnosis of EB according to Vienna Classification were included. OBJECTIVES: To evaluate the security and efficacy of ARF in patients with EB. RESULTS: 50 ARF treated patients were included with a medium follow up of 18 months. The median age was 58 years. 1.4 sessions of ARF perpatient were made to obtain EB erradication. The procedure morbidity was 6%, the more frequent complication was the esophageal stenosis (two cases). During the follow up, intestinal metaplasia recurrence was not observed. CONCLUSIONS: In the experience of our team, ARF is a secure procedure with low morbidity. These observations added to the published results help to evaluate the currentfollow up protocols.

Autoadjustable sutures and modified seldinger technique applied to laparoscopic jejunostomy.

This is a simple technique to be applied to those patients requiring an alternative feeding method. This technique has been successfully applied to 25 patients suffering from esophageal carcinoma. The procedure involves laparoscopic approach, suture of the selected intestinal loop to the abdominal wall and jejunostomy using Seldinger technique and autoadjustable sutures. No morbidity or mortality was reported.

Electrical stimulation to increase lower esophageal sphincter pressure after POEM.

INTRODUCTION: Postoperative reflux remains to be a challenge for patients with achalasia undergoing Heller myotomy. Similarly, per-oral endoscopic myotomy (POEM) is gaining rapid acceptance but the impossibility of adding a fundoplication is questioned as the main pitfall to control reflux. Electrical stimulation of the lower esophageal sphincter (LES) has emerged as a new alternative for the treatment of reflux disease. The objective of this study was to evaluate the potential benefits of combining electrical stimulation with endoscopic esophageal myotomy to prevent post procedural reflux. METHODS: Five pigs were subjected to POEM. After myotomy was completed, two electrical leads were implanted at the LES level and electrical stimulation was applied with the Endostim system with a regimen of 215 µs (5 mA amplitude), at 20 Hz for 25 min. LES pressures were recorded with manometry at pre and post-myotomy and after LES stimulation. RESULTS: Myotomy was completed successfully in all cases. Mean pre-myotomy LES pressure was 35.99 ± 8.08 mmHg. After myotomy, the LES pressure significantly dropped to 10.60 ± 3.24 mmHg (p = 0.03). Subsequent to LES-EST, LES pressure significantly increased to 21.74 ± 4.65 mmHg (p = 0.01). CONCLUSIONS: The findings of this study show that LES-EST in healthy animals increases LES pressure after POEM procedure, and could be useful tool to minimize gastroesophageal reflux.