Role of High-pressure Balloon Valvotomy for Resistant Pulmonary Valve Stenosis

Background. Pulmonary valve (PV) balloon valvotomy (BV) is considered the treatment of choice for isolated pulmonary valve stenosis (IPVS). While immediate and long-term results of PVBV are usually excellent, the reported results in dysplastic valves are variable. High-pressure (HP) PVBV in dysplastic valves that fail low-pressure (LP) PVBV may increase success rate, reducing the need for surgical interventions. Methods. We reviewed all cases of IPVS in patients < 3 years old, who underwent PVBV between August 1999 and March 2004. Study outcomes were initial success rate (gradient post PVBV < 30 mm Hg) and freedom from reintervention. Possible predictors of failure to LP-PVBV were explored (age, hemodynamic data, PV leaflet maximal thickness, diameter/z-scores for PV annulus, sinotubular junction, and subvalvar area). Results. All 35 patients (16 neonates, 5 with critical IPVS) underwent LP-PVBV with immediate success in 27 (80%). All eight patients who failed LP-PVBV successfully underwent HP-PVBV. Upon follow-up (27 +/- 24 months), two patients (6.9%) required reintervention after LP-PVBV (LP-PVBV at 3 months, HP-PVBV at 2 months with success, both reintervention free thereafter), and one patient (12.5%) after HP-PVBV (surgical right ventricular outflow tract patch at 33 months) (Fisher's exact test = 0.5). There were no major immediate or long-term complications. After nonparametric median regression, age (2 vs. 11 months, P < .001) and PV maximal thickness (0.13 vs. 0.24 cm, P = .026) were the only predictors of failure to LP-PVBV. Conclusion. HP-PVBV can be performed safely in patients with IPVS that fail LP-PVBV, with high success rate and acceptable long-term results. Failure to LP-PVBV is difficult to predict.