Right ventricular outflow tract reconstruction using a Goretex membrane monocusp valve in infant animals

We examined the feasibility of using a polytetrafluoroethylene membrane (goretex) valve and transannular patch (TAP) for right ventricular outflow tract (RVOT) reconstruction in growing animal models. Eleven infant goats (Group A) and 12 infant sheep (Group B) underwent RVOT reconstruction under cardiopulmonary bypass. In Group A, a monocusp valve was constructed of goretex, and the RVOT was roofed over utilizing a TAP of bovine pericardium. In Group B, both a monocusp valve and a TAP were constructed of goretex. Animals were sacrificed at 6 or 12 postoperative months. Two goats in Group A died at 9 days and 4 months postoperatively due to RVOT obstruction caused by thrombus formation. Seven goats in Group A and 11 in Group B showed no pressure gradient across the valve. All animals in Group B revealed mild to moderate valvular insufficiency, but no ventricular deterioration. In contrast to the bovine pericardium, which showed a prominent fibroinflammatory reaction with calcified areas causing TAP shrinkage and RVOT stenosis, there was minimal calcification and inflammatory reaction directed against the goretex valve and TAP. We conclude that goretex can be used as a material from which to create both a monocusp valve and TAP for long-term RVOT reconstruction.