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 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.

Resección laparoendoscópica de tumor de la unión gastroesofágica / Laparoendoscopic resection of a tumor of the gastroesophageal junction

RESUMEN La resección gástrica atípica ha demostrado ser beneficiosa para tumores submucosos. La técnica pre senta mayor riesgo cuando estos se desarrollan próximos a la unión esófago-gástrica (UEG). Para esta limitación se propuso la resección intragástrica mediante una técnica mixta combinando laparoscopia y endoscopia. En nuestro medio no existen publicaciones al respecto. Se trata de una mujer de 42 años, con lesión subepitelial-subcardial de 2 cm, evaluada mediante videoendoscopia alta (VEDA), compa tible con tumor del estroma gastrointestinal (GIST) evaluado mediante ecoendoscopia. La lesión fue resecada mediante abordaje combinado laparoendoscópico. Bajo visión laparoscópica se introdujeron en cavidad abdominal trocares con balón, y bajo visión endoscópica intragástrica se introdujeron estos en el estómago y se fijó la pared gástrica a la pared abdominal insuflando dichos balones. Posterior mente se realizó la resección de la lesión con sutura mecánica. El abordaje combinado es seguro y eficaz, simple en manos entrenadas, pero constituye una opción reproducible en casos seleccionados.

ABSTRACT Atypical gastric resection has proved to be beneficial to treat submucosal tumors. The technique is more difficult when these tumors develop next to the gastroesophageal junction (GEJ). Intragastric resection combining endoscopic and laparoscopic approach was proposed to solve this limitation. There are no publications about this technique in our environment. A 42-year-old female patients with a 2-mm subepithelial tumor below the cardia evaluated by upper gastrointestinal (UGI) videoendoscopy and endoscopic ultrasound suggestive of a gastrointestinal stroma tumor (GIST) underwent resection using the combined laparo-endoscopic approach. Under laparoscopic guidance, balloon-tipped trocars were introduced in the abdominal cavity and then into the stomach using endoscopic view. The balloons were inflated to fix the gastirc wall to the abdominal wall. The lesion was resected using mechanical stapler. The combined approach is safe and efficient, and simple to perform for trained professionals, constituting a reproducible option in selected cases.