Evaluation of linear magnets for side-to-side cholecystoduodenal anastomosis in a swine model over 6 weeks

Background: Cholecystectomy in debilitated patients following percutaneous gallbladder drainage for acute cholecystitis is a feared intervention with high morbidity. An alternative drainage technique, magnetic cholecystoduodenostomy (CCD), may be feasible and safer. Recently, the magnetic compression anastomosis device (MCAD) has created patent, leak-free anastomoses without foreign materials retained in the body. We evaluated the feasibility and healing efficacy of a new design of MCAD to effect CCD in a porcine model. Materials and methods: An optimized CCD MCAD was developed through four design iterations, each of which was evaluated in side-to-side magnetic CCD. In Landrace-Yorkshire pigs, a cylindrical magnet was positioned in the gallbladder, a linear magnet was placed in the proximal duodenum, and the devices were magnetically aligned without fixation. Abdominal radiography was performed over six weeks to observe device dislodgement and expulsion. At necropsy, anastomosis patency was assessed, and anastomosis and enterotomy healing were evaluated. Results: The fourth optimized CCD MCAD iteration was placed in four young swine. The pigs gained weight normally, adding an average of 17.4 kg (14.4–18.9). All four magnet pairs dislodged from the anastomosis between 27 and 35 days; two pairs were expelled between 34 and 49 days. At necropsy, sizable patent anastomoses were noted (mean circumference 33.5 mm [17–57]; calculated diameter 10.7 mm [5.4–18.1]). Evaluation showed well-healed anastomoses. Intraoperatively and perioperatively, the MCAD CCD and procedure resulted in no anastomotic leak, bleeding, infection, stricture, or death. Conclusions: A novel linear magnetic compression anastomosis device achieved patent side-to-side CCD in swine with excellent anastomotic healing and no complications. Magnetic MCAD cholecystoduodenostomy may be appropriate for clinical evaluation.