Balloon pulmonary valvuloplasty in the neonatal period. The clinical and echocardiographic effects

Objective: To analyze the efficacy of balloon pulmonary valvuloplasty (BPV) as the elective treatment for neonatal critical pulmonary valvar stenosis (PVS).

Methods: The results of clinical and echocardiographic features before and after the BPV were reviewed in 29 neonates (18+/-12 days of life). Different hemodynamic and 2-D color Doppler echocardiographic were evaluated. The BPV result was classified as favourable if no other balloon or surgical therapy was required to normalise pulmonary flow and achieve a sustained right ventricle-pulmonary artery (RV-PA) Doppler gradient below 40 mmHg. It was considered unfavourable if the neonate died, needed surgery or redilation and/or the RV-PA Doppler gradient was > or =40 mm Hg. The study developed in three phases: pre BPV immediate post BPV until the hospital discharge (14+/-11 days), and in the mid-term follow-up of between 8 and 96 months (51+/-31 months).

Results: Mortality was not registered with BPV. The RV/left ventricular systolic pressure decreased from 1.4+/-0.3 to 0.8+/-0.3 (p<0.01) as a consequence of the dilation, and the the systemic oxygen saturation increased from 85 +/-12 to 92+/-6% (p<0.01). The RV-PA Doppler gradient diminished from 86+/-18 to 28+/-16 mm Hg immediately after BPV (p<0.01) and was registered at 13+/-6 mm Hg in the follow-up (n = 24). The RV-PA junction Z value grew from -1.25+/-0.9 before valvuloplasty to -0.51 +/-0.7 at the final echocardiogram (p<0.01). No changes in the tricuspid diameter were detected between both periods of time. Five neonates obtained unsatisfactory results: 4 in the immediate post BPV (systemic-pulmonary artery shunt 2, transannular patch 2), and 1 in the mid-term follow-up (valvectomy + transannular patch). The actuarial curve reflects that 82,7% of the patients were free form reinterventions at 8 years.

Conclusions: BPV is safe and effective to relief PVS in the neonate. The balloon promotes advantageous changes in both, pulmonary annulus and the right ventricle. In addition, the RV-PA Doppler gradient observations in the follow-up, support the expectation that the BPV is a "curative" therapy.