An experimental study on long term outcomes after magnetic esophageal compression anastomosis in piglets

BACKGROUND/PURPOSE

Previous studies have shown that a patent, watertight esophageal anastomosis can be accomplished safely using specially-shaped magnets in piglets. However, it is unclear whether such a magnetic esophageal compression anastomosis (MECA) remains patent in the long-term. The purpose of this study was to evaluate the long-term outcome of MECA in an experimental pig model over an observation period of 2 months.

METHODS

Ten piglets underwent creation of an MECA with custom-made 8 mm magnets and a U-shaped esophageal bypass loop to allow peroral nutrition at eight weeks of life. Two weeks later, the bypass loop was closed surgically, requiring the pigs to swallow via the newly created magnetic compression anastomosis. The pigs were fed soft chow for 2 months. They were monitored for weight gain and signs of dysphagia. At the endpoint of two months, esophagoscopy and contrast esophagography was performed. After removal of the esophagus, the tissues were macroscopiocally and histologically assessed.

RESULTS

Six piglets survived until the endpoint. In two pigs, closure of the bypass loop failed, these demonstrated mean weight gain of 792 gs/day [95% Confidence interval 575 to 1009 gs/day]. Weight gain in four pigs that exclusively fed via the magnetic anastomosis averaged 577 gs/day [95% confidence interval 434 to 719 gs/day (p = 0.18)]. There were no signs of dysphagia. All magnets passed with the stool within 16 days. After 2 months, a well-formed magnetic compression anastomosis was visible and easily negotiated with a 6.5 mm endoscope. Esophogram and macroscopic findings confirmed patentency of the esophageal anastomoses. Histopathology showed a circular anastomosis lined with contiguous epithelium.

CONCLUSION

MECA creates a long-term functional and patent anastomosis in pigs. This concept may facilitate minimally-invasive esophageal atresia repair by obviating a technically challenging and time-consuming hand-sewn anastomosis.

Novel Device for Endoluminal Esophageal Atresia Repair: First-in-Human Experience

Thoracoscopic esophageal atresia (EA) repair affords many benefits to the patient; however, intracorporeal suturing of the anastomosis is technically challenging. Esophageal magnetic compression anastomosis (EMCA) is a compelling option for endoluminal EA repair, but available EMCA devices have prohibitive rates of recalcitrant stricture. Connect-EA is a new endoluminal EMCA device system that employs 2 magnetic anchors with a unique mating geometry designed to reliably create a robust anastomosis and decrease rates of leak and stricture. We describe our first-in-human experience with this novel endoluminal device for staged EA repair in 3 patients (Gross type A, B, and C) at high risk for conventional surgical repair. First, the esophageal pouches were approximated thoracoscopically. After acute tension subsided, the device anchors were endoscopically placed in the esophageal pouches and mated. Anchors were spontaneously excreted in 2 cases. Endoscopic repositioning and retrieval of the anchors were required in 1 patient because of narrowed esophageal anatomy. There were no perioperative complications. Patients were managed for 14 to 18 months. The strictures that developed in the patients were membranous and responded well to dilation alone, resolving after 4 to 5 outpatient dilations. Gastrostomies were closed between 6 and 11 months and all patients are tolerating full oral nutrition. Early experience with this new endoluminal EMCA device system is highly favorable. The device offers considerable benefit over conventional handsewn esophageal anastomosis and anastomotic outcomes are superior to available EMCA devices.

An experimental study on magnetic esophageal compression anastomosis in piglets

INTRODUCTION

Fashioning a patent, watertight anastomosis in patients with esophageal atresia is a challenging task in pediatric surgery, particularly when performed under tension. A reproducible suture-less alternative would decrease operative time. We evaluated magnetic esophageal compression anastomoses in a novel bypass-loop swine model.

METHODS

Eight-week-old piglets underwent thoracotomy to mobilize the esophagus at the carina to create a U-shaped loop. Custom-made 8 mm diameter Neodymium Magnets were inserted into the esophagus proximal and distal to the loop, then mated side-to-side at the future anastomosis site. Pigs were observed for 8 (n = 4), 10 (n = 6), and 12 (n = 2) days and then sacrificed. The magnetic compression anastomosis was evaluated macroscopically, by radiography, burst pressure testing, and histology.

RESULTS

All 12 pigs survived until the endpoint. Separation of the magnets occurred at a median of 9 days. Contrast esophagrams showed patency and no leak. All anastomoses withstood pressures well over 13 kPa without leak. Histopathology showed epithelialized circular scar tissue.

CONCLUSION

Magnetic compression anastomoses of the esophagus using our specially-designed magnets are formed between the 8th and 10th postoperative day, are patent and mechanically resistant to supraphysiologic intraluminal pressures. These data lay the basis for a potential clinical application in patients born with esophageal atresia.

LEVEL OF EVIDENCE

Not applicable (experimental animal study).