Congenital diseases as pulmonary atresia, tetralogy of Fallot, among others, have been corrected using the extracardiac conduits. There is a variety of conduits valved or not that make possible the access of sanguineous flux from right ventricle to pulmonary circulation. However, the synthetic conduits with biologic or metalic valves shows prosthesis degeneration and obstruction problems and peeling of the conduit, moreover, they are very expensive. The experience with treated bovine pericardium showing it is impermeable and easy to suture, led to the production of valved conduits that in this study were evaluated for obstruction, calcification and stretching. The utilization of an animal experimental model allowed the detailed periodic evaluation by echodopplercardiography and cateterism during one, three and six months. The recuperated conduits were studied by optical microscopy and X ray, with several parts of the bioprosthesis analysed. The microscopic examination showed the conduits pericardium preserved with signs of pseudo-endotelization, and the majority of valves with moderate calcification, but with good function yet. The surgery technique without extracorporeal circulation and the results with the follow-up of five animals during six months are presented and discussed. The authors conclude that the bovine pericardium valved conduit showed good results in the right ventricule outlet, allowing to expect a satisfatory result when applied in human beings by the known relation of acelerated degeneration of the biological prostheses on the studied experimental model, several times greater than in man.
valvar tube graft
