Gradual attenuation of a congenital extrahepatic portosystemic shunt with a self-retaining polyacrylic acid-silicone device in 6 dogs.

Objective: To determine the ability of a polyacrylic acid-silicone radiolucent self-retaining gradual occlusion device (PAS-OD) to attenuate congenital extrahepatic portosystemic shunts (EHPSS) in dogs.

Study Design: Prospective clinical trial.

Animals: Six client-owned dogs with single, congenital EHPSS.

Methods: Serum bile acids (SBA), abdominal ultrasonography, and computed tomographic angiography (CTA) were performed preoperatively and at 4 and 8 weeks postoperatively. Each dog was treated for EHPSS by placement of a PAS-OD.

Results: PAS-OD were placed without complication an average of 4.3 seconds (range, 3-7) after isolation of the shunt. Median surgical time was 38.5 minutes (range, 28-84) including concurrent procedures. All dogs recovered from surgery without complications. SBA were normal in 5 of 6 dogs at 4 and 8 weeks after surgery. The shunt was completely attenuated in 2 of 6 dogs at 4 weeks and in 4 of 6 dogs at 8 weeks, without evidence of acquired shunt formation in any dog. The size and velocity of the portal vasculature were improved in 5 of 6 dogs according to 8-week postoperative CTA and ultrasonography results, respectively. The remaining dog had a persistently decreased portal vasculature size but a normal velocity according to 8-week postoperative CTA and ultrasound results, respectively.

Conclusion: The PAS-OD led to complete attenuation in 4 of 6 dogs and partial attenuation with mild residual flow of 2 EHPSS over an 8-week period in dogs.

Clinical Significance: The PAS-OD is a new option for gradual occlusion of congenital EHPSS over 8 weeks.