721-1 Percutaneous Balloon Dilation as Initial Treatment for Critical Aortic Stenosis. Results Up to 8.3 Years Follow-up In 46 Consecutives Neonates

The purpose of this study is to report our results with balloon dilation (BD) of critical aortic stenosis (AS) in neonates. From 1985 to ‘91, 46 consecutive babies<33 days of age had BD for critical AS. The median age was 5 days, and the mean weight was 3.2kg; 41 (89%) was in congestive heart failure (CHF) or shock, 33 (80%) intubated. Associated cardiac abnormalities were present in 42 (91%). The BD, performed retrograde in 43 (umbilical artery 23, femoral artery 20), was completed in all, and with success in 41 (89%). The final balloon to aortic annulus ratio was 0.91±0.05. The overall mortality was 35% (11 early and 5 late deaths 1.6 to 17 mos of follow-up). Of these 16, 4 were considered related to BD, and 12 to associated left-sided lesions. All babies who had BD via femoral artery had pulse loss, and anti-thrombotic therapy restored pulses in 7 (35%). Significant aortic regurgitation (AR) post-BD was observed in 5 (11%) babies. An anatomic risk factor score for two-ventricle repair(Rhodes et al, 1991) was retrospectively measured, and 13 (38%) babies had a score≥2 (critical AS with 2 or more associated left-sided obstructive lesions; high mortality). No neonate with an anatomic score≥2 survived longer than 4mos, except 1 who underwent successful Norwood operation. In univariante analysis, an age of<3 days, a presentation in CHF or shock, and an anatomic score ≥2 were found to be related to mortality, but in a multivariante analysis, only the anatomic score was significant (p=0.001). Reintervention was undertaken by 1 month in 22%, by 4 mos in 30%, and by 88 mos in 41%; the main indication was AS. At follow-up of 1.4 to 83 yrs (4.3±1.8yrs), 30 (65%) were alive, and the clinical status was considered excellent or good in 90%. No child had leg length discrepancy. At Doppler study, a maximum gradient >50mmHg was found in 10 (33%), and significant AR was present in 4 (13%).In conclusionwhen no more than 1 associated left-sided obstructive lesion is present. BD for critical AS is effective; at 8.3 yrs of follow-up, the probability of being alive is 88%, and of being free from reintervention is 59%