As new treatment strategies are developed which outperform previous approaches in terms of safety, efficacy and long-term results, a reappraisal of old therapeutic dogmas is warranted, including lowering the threshold for intervention. Pulmonary valvuloplasty was introduced in 1982 to treat children and adults with significant isolated pulmonary valve stenosis (PS) and provided a very reliable tool to treat the problem avoiding cardiac surgery, with very good long-term results in terms of reinterventions as well as functional outcomes.1 ,2

Besides the neonate with critical PS, the same technique has been used to treat older children and adults with isolated PS. In these latter patient groups, the physiopathological mainstay behind the recommendation for treatment is that significant PS (defined as a Doppler velocity >4.0 m/s) creates such a significant afterload resistance and right ventricular (RV) hypertension that the RV is not able to increase stroke volume during exercise as it should. Additionally, RV hypertrophy and stiffness related to structural alterations, small infarcts and fibrosis limits ventricular preload, causing a significant drop in RV end diastolic volume during exercise and a blunted RV stroke volume response. Ultimately, these changes limit exercise capacity and cause symptoms.3 ,4 As such, severe PS is not associated with a good prognosis if left untreated.

Conversely, the available evidence suggests that the natural history …