H-shaped partial splenorenal shunting with the use of a reinforced graft made of porous polytetrafluoroethylene. / N-obraznoe partsial'noe splenorenal'noe shuntirovanie s ispol'zovaniem armirovannogo proteza iz poristogo politetraftorétilena.

AIM: The study was aimed at improving the immediate and remote results of splenorenal bypass grafting. PATIENTS AND METHODS: A total of 57 patients presenting with hepatic cirrhosis, portal hypertension, and recurrent haemorrhage from oesophageal varices underwent an H-shaped partial splenorenal shunt procedure using an externally reinforced 1.5-2.0-cm-long synthetic graft with a diameter equalling half of that of the splenic vein in an end-to-side fashion. Assessment of efficacy of shunting was based on intraoperative measurement of venous pressure in the portal system before and after shunting, the findings of Doppler ultrasonography of the linear velocity of blood flow in the portal, splenic, and left renal veins in the early postoperative period, as well as computed tomography, esophagogastroscopy, and assessment of the degree of hepatic encephalopathy in the remote postoperative period. RESULTS: The findings of intraoperative measurement of venous pressure in the portal vein system before and after shunting demonstrated a statistically significant decrease in (normalization of) portal pressure in all patients after bypass grafting (p≤0.05). There were no severe postoperative complications, in-hospital mortality, nor events of decompensation of hepatic insufficiency. According to the findings of Doppler ultrasonography of the linear velocity of blood flow and control computed tomography after surgery, the splenic vein, left renal vein and the conduit between them remained patent at all terms of postoperative follow up. The findings of control esophagogastroscopy revealed a statistically significant decrease in the degree of oesophageal varices at 3, 6, and 9 months after shunting (p≤0.05). There was no statistically significant difference in the change of the degree of hepatic encephalopathy at 3, 6, and 9 months after shunting (p=0.853, p=0.712, and p=0.581, respectively). At various terms after surgery, nine patients underwent deceased donor liver transplantation, with the splenorenal shunt ligated intraoperatively. CONCLUSION: This method of splenorenal shunting makes it possible to decrease the risk of bleeding from oesophageal varices and venous thromboses in vascular anastomoses, as well as complications resulting from using autovenous conduits, to decrease the risk of decomposition of hepatic insufficiency and the frequency of the development of encephalopathy in the postoperative period. Besides, this method makes it possible to easily dismantle the previously created artificial portocaval shunt in the process of liver transplantation.

Peculiarities of vitalization of grafts made of porous polytetrafluoroethylene in reconstruction of major veins (an experimental study). / Osobennosti vitalizatsii protezov iz poristogo politetraftorétilena pri rekonstruktsii magistral'nykh ven (éksperimental'noe issledovanie).

Increased incidence of locally disseminated malignant neoplasms with invasion of major veins compels modern surgery to search for an optimal material for reconstruction of major veins. Presented herein are the results of an experimental study aimed at exploring patency and peculiarities of vitalization of grafts made of porous polytetrafluoroethylene (7th generation, 2010) manufactured by the Closed Joint Stock Company 'Research and Production Complex 'Ecoflon' (St. Petersburg, Russia) with an internal diameter measuring 4.0 mm and used for reconstruction of major veins and arteries with a follow up period up to 270 days. Vitalization of porous polytetrafluoroethylene grafts in the venous position is comparable to that in the arterial position, having similar patterns. Both in the arterial and venous position, vitalization of the graft proceeds at the expense of 'crawling' of the neointima from the anastomoses to the centre of the graft. To distinctive peculiarities of vitalization of grafts in the venous position belong statistically significantly larger thickness of the neointima in the venous position at all stages of the study, lack of statistically significant difference of the neointimal thickness near the edges and in the central part of the graft in the venous position at 270 days. Neither thromboses nor haemodynamically meaningful stenoses of the porous polytetrafluoroethylene grafts and anastomoses in the venous position, despite low velocity of blood flow and its laminar pattern, were observed at any terms of follow up. The obtained findings are indicative of the possibility and validity of using porous polytetrafluoroethylene grafts for reconstruction of major veins in clinical practice.