Magnetic Anastomosis Rings to Create Portacaval Shunt in a Canine Model of Portal Hypertension

J Gastrointest Surg. 2019 Nov;23(11):2184-2192. doi: 10.1007/s11605-018-3888-5. Epub 2018 Aug 21.

Abstract

Purpose: This study evaluated a novel magnetic compression technique (magnamosis) for creating a portacaval shunt in a canine model of portal hypertension, relative to traditional manual suture.

Methods: Portal hypertension was induced in 18 dogs by partial ligation of the portal vein (baseline). Six weeks later, extrahepatic portacaval shunt implantation was performed with either magnetic anastomosis rings, or traditional manual suture (n = 9, each). The two groups were compared for operative time, portal vein pressure, and serum biochemical indices. Twenty-four weeks post-implantation, the established anastomoses were evaluated by color Doppler imaging, venography, and gross and microscopic histological examinations.

Results: Anastomotic leakage did not occur in either group. The operative time to complete the anastomosis for magnamosis (4.12 ± 1.04 min) was significantly less than that needed for manual suture (24.47 ± 4.89 min, P < 0.01). The portal vein pressure in the magnamosis group was more stable than that in the manual suture group. The blood ammonia level at the end of the 24-week post-implantation observation period was significantly lower in the magnamosis group than in the manual suture group. Gross and microscopic histological examinations revealed that better smoothness and continuity of the vascular intima had been achieved via magnamosis than with manual suture.

Conclusion: Magnamosis was superior to manual suture for the creation of a portacaval shunt in this canine model of portal hypertension.

Keywords: Canine model; Magnamosis; Magnetic compression technique; Portacaval shunt; Portal hypertension.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anastomosis, Surgical
  • Anastomotic Leak / surgery
  • Animals
  • Disease Models, Animal
  • Dogs
  • Hypertension, Portal / surgery*
  • Liver Function Tests
  • Magnetic Phenomena
  • Magnets*
  • Male
  • Operative Time
  • Phlebography
  • Portacaval Shunt, Surgical / instrumentation*
  • Portacaval Shunt, Surgical / methods
  • Portal Pressure
  • Portal Vein / surgery
  • Suture Techniques
  • Sutures
  • Ultrasonography, Doppler, Color