Opportunities in pulmonary valve replacement.

Pulmonary regurgitation is the most important residual lesion after initial surgical correction for pulmonary (sub)valvular stenosis in the early life of patients with tetralogy of Fallot or isolated pulmonary stenosis. Symptomatic or asymptomatic patients with severe right ventricular dilatation due to pulmonary regurgitation may benefit from pulmonary valve replacement. Surgery is ideally performed before the right ventricle becomes irreversibly damaged as a result of longstanding volume overload. However, the beneficial effects must be weighed up against the problems associated with degradation of the allograft, which often result in (numerous) reoperations. Owing to the higher risk of thromboembolic events in mechanical prosthesis and the lifetime need for anticoagulation, allografts are the most widely used prosthesis. Degradation of the allograft often leads to reoperation, mostly 10-20 years after initial implantation. For a patient receiving his first allograft at 20 years of age, several reoperations will have to be performed later in life. Percutaneous pulmonary valve implantation has the potential to decrease the number of surgical reoperations.