Construction of peritoneal venous valves: an experimental study in rats and piglets

In the search for new techniques to improve venous valve insufficiency, a peritoneal patch with a mesothelial layer on either side was employed in the venous circulation to construct a venous valve de novo. This material was used because of the resemblance in fibrinolytic activity of mesothelial cells to endothelium. The behavior of double-sided flaps of peritoneum was first studied on only one side in the caval vein wall of 10 rats. All veins remained open, and smooth incorporation of the patch into the vein wall was observed. It was therefore decided to use the same material for construction of a cusp blade in the venous circulation. This venous reconstruction was microsurgically performed in 21 rats and 4 piglets. In our hands, intramuscular anesthesia proved superior to intraperitoneal analgesia in rats. For the piglets mechanical ventilation and general anesthesia were used. In 9 of 21 rats a fair or good result was observed, although it did not seem possible to create a fully competent valve with only one cusp blade in the 1.5-mm-diam caval veins. The same fact evolved from the study using four 7-mm-diam piglet veins. All peritoneal flaps in the venous circulation demonstrated rebuilding of their structure, perhaps induced by the relatively exaggerated central venous flow. To our knowledge, this technique has never been used before. It seems to offer many advantages in the venous circulation, where hardly any thrombogenic surface is tolerated in contrast to the arterial circulation. Application in humans is yet premature, but future research may resolve several problems that occurred in this study.