Over the years, management of critical pulmonary stenosis in young infants has evolved from surgical reconstruction of the right ventricular outflow tract and closed pulmonary valvotomy to transcatheter balloon valvoplasty. Our study aimed at evaluating how the changing policy for management had affected the immediate and long term outcomes of babies with this cardiac lesion. Interventions were made in 34 infants at a median age of 8.5 days (2–90 days). Reconstruction of the right ventricular outflow tract reconstruction was performed in 10 patients, closed pulmonary valvotomy in 13, and balloon valvoplasty in 11. Initial procedure-related mortality was 50%, 15% and 0% respectively. Multivariate analysis revealed transannular patching of the right ventricular outflow tract, and male sex, to be significant factors for death. For the 27 survivors, the ratio of right ventricular to systemic systolic pressure decreased from 1.6 ± 0.3 to 0.3 ± 0.2 after reconstruction of the outflow tract, 1.8 ± 0.5 to 0.8 ± 0.4 after closed valvotomy, and 1.8 ± 0.6 to 0.9 ± 0.3 after balloon valvoplasty. The decrease was significantly greater after patch reconstruction (p=0.025) that required no further reinterventions. The overall rate of reintervention for the survivors was 37% (10/27). The freedom from reintervention after closed valvotomy was 82%, 64% and 51% at 1, 5 and 10 years respectively. The figure remained at 78% at both 1 and 5 years (p=0.66) after balloon valvoplasty. The higher reintervention rate for closed valvotomy corresponded to the significantly greater residual gradient across the pulmonary valve noted on follow-up (p=0.01). Reinterventions included balloon dilation (n=6), reconstruction of the outflow tract (n=4), and 1 each of ligation of an arterial duct and systemic-pulmonary arterial shunting. The risk factor for reintervention was a hypoplastic right ventricle. In conclusion, transcatheter balloon valvoplasty appears to be the optimum initial approach in view of its low mortality, efficacy at relieving the obstruction, and low rate of reintervention.

A retrospective study was undertaken of patients with hypoplastic right ventricles, either with pulmonary atresia and intact ventricular septum or critical pulmonary valvar stenosis, and duct-dependent pulmonary blood flow who were investigated at the Royal Brompton Hospital between January 1976 and December 1990. The diagnosis was made on the basis of at least one diagnostic method (cross-sectional echocardiography, cardiac catheterization and angiography, or autopsy). Of the patients, 56 (82%) were found to have an imperforate pulmonary valve or infundibulum (pulmonary atresia), while 12(18%) had critical pulmonary valvar stenosis. The ratio of the diameters of the tricuspid and mitral valvar orifices was measured angiographically during diastole, and the right ventricle was analyzed according to the presence or overgrowth of the inlet, apical trabecular and outlet components. A correlation was made between the severity of the disease and the outcome. The overall mortality was 53% when those not undergoing any surgery were excluded, and significant differences were found between the group dying and those who survived. The incremental risk factors for death were a ratio between the diameter of the tricuspid and mitral valves of less than 0.6; the presence of fistulous communications with the coronary arteries; and obliteration of the apical trabecular component of the right ventricle. There was no significant difference between the group with pulmonary valvar atresia and the group with critical stenosis of the pulmonary valve.