Differential regulation of MMP-2 in the gastrohepatic ligament of the gastroesophageal junction

Dynamics of hiatal hernia recurrence: how important is a composite crural repair?

INTRODUCTION

Hiatal hernia recurrence rates vary widely. The true causes of recurrences are not fully understood but likely multifactorial. Surgical approaches and techniques have evolved over time to try and reduce recurrence rates after hiatal hernia repair. Our objective is to provide a current review on the physiology of hiatal hernias and the importance of a composite crural repair on hiatal hernia recurrence rates; more specifically, for this review, a composite repair is defined as a repair requiring more than primary closure of the crura.

METHODS

A recent review of the literature was conducted to identify studies reporting on hiatal hernia pathophysiology, stress, and tension, as well as the role of composite repair.

RESULTS

There is a paucity of studies focusing on the pathophysiology of hiatal hernias and recurrence rates. Articles that report on the pathophysiology of the hiatus were found to have alterations of the extracellular matrix, collagen composition, changes in metalloproteinases (MMPs), and differences in genetic composition. The role of composite repair on reducing recurrence rates is not well studied.

CONCLUSIONS

Hiatal hernias remain a complex problem with no ideal surgical technique. It is likely that the pathophysiology of hiatal hernias is multifactorial, and more studies need to be done to better understand the potential underlying mechanisms for hiatal hernias so this may also further identify the ideal surgical repair.

Management of acute upside-down stomach

Background

Upside-down stomach (UDS) is characterized by herniation of the entire stomach or most gastric portions into the posterior mediastinum. Symptoms may vary heavily as they are related to reflux and mechanically impaired gastric emptying. UDS is associated with a risk of incarceration and volvulus development which both might be complicated by acute gastric outlet obstruction, advanced ischemia, gastric bleeding and perforation.

Case presentation

A 32-year-old male presented with acute intolerant epigastralgia and anterior chest pain associated with acute onset of nausea and vomiting. He reported on a previous surgical intervention due to a hiatal hernia. Chest radiography and computer tomography showed an incarcerated UDS. After immediate esophago-gastroscopy, urgent laparoscopic reduction, repair with a 360° floppy Nissen fundoplication and insertion of a gradually absorbable GORE® BIO-A®-mesh was performed.

Conclusion

Given the high risk of life-threatening complications of an incarcerated UDS as ischemia, gastric perforation or severe bleeding, emergent surgery is indicated. In stable patients with acute presentation of large paraesophageal hernia or UDS exhibiting acute mechanical gastric outlet obstruction, after esophago-gastroscopy laparoscopic reduction and hernia repair followed by an anti-reflux procedure is suggested. However, in cases of unstable patients open repair is the surgical method of choice. Here, we present an exceptionally challenging case of a young patient with a giant recurrent hiatal hernia becoming clinically manifest in an incarcerated UDS.

Hiatal hernias: a review of the pathophysiologic theories and implication for research

BACKGROUND

The pathophysiology of hiatal hernias is incompletely understood. This study systematically reviewed the literature of hiatal hernias to provide an evidence-based explanation of the pathogenetic theories and to identify any risk factors at the molecular and cellular levels.

METHODS

A systematic search of the Medline and Pubmed databases on the pathophysiology of hiatal hernias was performed to identify English-language citations from the database inception to December 2010.

RESULTS

Although few studies have examined the relationship of molecular and cellular changes of the diaphragm to the pathogenesis of hiatal hernias, there appear to be three dominant pathogenic theories: (1) increased intraabdominal pressure forces the gastroesophageal junction (GEJ) into the thorax; (2) esophageal shortening due to fibrosis or excessive vagal nerve stimulation displaces the GEJ into the thorax; and (3) GEJ migrates into the chest secondary to a widening of the diaphragmatic hiatus in response to congenital or acquired molecular and cellular changes, such as the abnormalities of collagen type 3 alpha 1.

CONCLUSIONS

The pathogenesis of hiatal hernias at the molecular and cellular levels is poorly described. To date, no single theory has proved to be the definitive explanation for hiatal hernia formation, and its pathogenesis appears to be multifactorial.

Collagen type I:III ratio of the gastroesophageal junction in patients with paraesophageal hernias

BACKGROUND

The purpose of this study was to examine the biological environment of the esophageal hiatus through analysis of the collagen content within the gastrohepatic ligament (GHL), gastrophrenic ligament (GPL), and phrenoesophageal ligament (PEL) in patients with type I hiatal hernias (HH) and type III paraesophageal hernias (PEH).

METHODS

A control group (N=10) and patients with type I HH (N=10) and type III PEH (N=10) were included in the analysis. Specimens of the GHL, PEL, and GPL were collected intraoperatively. Slides stained with sirius red/fast green were created and ten photos at 400×magnification were taken of each specimen. Axiovision 4.7 (Zeiss) photo analysis software was employed for quantification of collagen I (red) and III (green) by calculating color area (μm2). Statistical significance (p<0.05) was determined using a one-way ANOVA and Fisher's LSD post-test.

RESULTS

Cross-polarization microscopy revealed that the collagen I content was similar in the three study groups for the GHL, greater in the type III PEH group and in the control group compared to the type I HH group for the PEL, and greater in the type III PEH group compared to control group for the GPL. Collagen III quantity was greater in the control group than in the type I HH group for each ligament, and greater in the GHL and PEL when compared to the type III PEH group. Type III PEH patients had greater collagen III quantity than did type I HH patients for each ligament. Collagen type I:III ratio of the GHL was greater in both hernia groups compared to the control group. Type III PEH patients contained a higher I:III ratio than both the control and type I HH groups with respect to the PEL. There was no difference in the ratio with evaluation of the GPL for the three groups.

CONCLUSION

Evaluation of the esophageal hiatus revealed that patients with PEH have a different biological environment with regard to collagen content compared to control patients. The collagen I:III ratio of the study groups was equal to or greater than the control group. Collagen deficiency in the GE junction supporting ligaments does not appear to be an etiology of PEH formation.