Long term outcome of mechanical valve prosthesis in the pulmonary position

ObjectivesAssessment of the long term outcome of mechanical valve prosthesis at pulmonary position in a population of grown-up congenital heart disease patients from a tertiary referral center.MethodsFrom 1977 to 2007, 22 consecutive patients underwent a total of 25 pulmonary valve replacements with mechanical prosthesis. The most frequent underlying cardiac condition was tetralogy of Fallot (n = 16, 64%) and the mean age at the time of pulmonary valve replacement was 32 ± 11 years (range 14–50 years).ResultsThe postoperative mortality rate was 4% (n = 1) with no late deaths documented after a mean follow-up of 7.6 ± 7.6 years (range 0.29–24 years). No major bleeding episodes occurred. Three patients presented with valve thrombosis in the setting of long term anticoagulation withdrawal and required valve re-replacement. Two of these patients, both with poor right ventricular function and overt clinical signs of right heart failure at the time of valve re-replacement, experienced further episodes of thrombosis despite correct anticoagulation. All episodes resolved with thrombolysis. After addition of antiplatelet treatment in one case and anticoagulation self-control, in the other, no further thrombosis has been documented.ConclusionsMechanical valve prosthesis may be an alternative to tissue valve prosthesis in patients with congenital heart disease requiring pulmonary valve replacement. Optimal anticoagulation is crucial and additional antiplatelet treatment should be considered. Our data also suggest that patients with severe right ventricular dysfunction and congestive heart failure might be at particular risk for valve thrombosis.