Roux-en-Y gastric bypass procedure is an effective treatment for morbid obesity. One of the most frequent complications after this operation is the appearance of a gastrojejunal anastomotic stricture(8). Treatment has traditionally been dilatation with either pneumatic balloon or Savoury Gillard Bougie’s.
Previous studies have shown up to 3 dilatations can be needed to achieve symptomatic relief(1). It is postulated that Linear stapled anastomosis are less likely to present with post-operative stricture compared to Circular stapler (9). Nonetheless stricture rates of up to 6% have been described with this technique(10). Gastro jejunostomy strictures can pose a difficult complication to deal with and can increase costs to the health care system.
LAMS have been traditionally used for management of pancreatic pseudocysts(11), however they have been increasingly used for other Upper gastro intestinal luminal strictures(6). They have also been used for low rectal strictures with some success(12). Longer self-expanding metal stents (SEMS) traditionally used for malignant strictures have been used for management of post RYGB leaks(13)(14) but not frequently for anastomotic strictures. These stents usually require x-ray for deployment and have an associated learning curve associated with using them.
Another concern with SEMS is the risk of migration both distally and proximally. This can result in subsequent need for removal of these stents. Migration rates of up to 52% have been described(15). This may even be higher without suturing the stent in. This increases the complexity of using stents as it generally involves a concurrent laparoscopy. Endoscopic clips can be unreliable. Once the stricture has resolved they have a tendency to slip through the area and migrate distally. Tissue ingrowth can also be an issue with SEMS. This did not tend to be a problem with LAMS
The Geometry of LAMS compared to SEMS makes them an attractive option for management of post-operative strictures in patients who have undergone RYGB. The dumb bell shape allows the stent to remain relatively fixed across a short stricture. In our experience LAMS was still prone to migration with a 4% migration rate. The advantage of using the LAMS was that none of these patients required either endoscopic or surgical removal unlike migration of a traditional SEMS. These often require laparoscopy and enterotomy to remove.
LAMS progressively dilate over a 48-72-hour time frame and can safely remain in for up to 106 days in our experience. This allows a slow steady radial pressure to be applied to the stricture. We believe this results in a more permanent outcome. Pneumatic dilatation may not apply enough radial force to the strictured segment of anastomosis to give a sustained result.
In our experience we found early removal (< 40 days) resulted in an increased risk of re stricture of the gastrojejunal anastomosis. Others have found up to 100 days median time for resolution of Gastric strictures(16), we propose initial placement for a minimum of 40 days before removal. It is unclear whether initial stricture diameter is a factor yet, but it is possible that the smaller the diameter of the stricture may have an impact in stricture resolution? Patients tolerated the LAMS device well and provided there was no proximal migration or placement over the Gastro Esophageal junction (GEJ) there were rarely symptoms and the device were tolerated well.
A variety of complication’s have been described after placement of LAMS and SEMS. Yang et al (16) reported a post procedural bleed requiring 2 units of blood after deploying a LAMS across a gastric stricture. We did not experience bleeding or ulceration associated with LAMS placement.
Proximal migration into the distal esophagus did occur in one patient with a short pouch. The patient complained of pain and reflux. On repeat endoscopy the stent was angulated and had not completely deployed. Simple removal and replacement of the stent resulted in a good outcome.
Another role may be in achieving adequate nutritional status prior to more definitive surgical treatment in patients with refractory strictures. This may limit the need to place Naso jejunal feeding tubes or feeding gastrostomy prior to formal surgical revision. These are often poorly tolerated and carry significant morbidity of their own.