Portacaval shunt with interposition of 6 mm H-graft of PTFE is a real partial shunt. In this experimental study, the operation has been well tolerated and has been compared with 8 mm H-graft and direct "vein to vein" portacaval shunt. Intraoperative data show that 6 mm is the ideal diameter for a portacaval shunt to prompt an experimental model based on partial decompression of portal bed in animals in this size.