Background: Critical aortic stenosis (AS) in neonates necessitates urgent intervention for patient survival. The optimal treatment, however, continues to be controversial and still has high morbidity and mortality in many centers. This study examined our late outcome, risks, and reoperations after the treatment of critical AS in neonates.
Methods: Sixty-six neonates (47 boys and 19 girls) underwent closed transventricular aortic valvotomy for critical AS between 1978 and 2000. The mean age at the first intervention was 15.1 +/- 19.6 days (range, 1 to 78). Their weight ranged from 1.4 to 6.2 kg (mean, 3.5 +/- 0.9 kg). Sixteen patients (23%) had isolated critical AS and normal or dilated left ventricles, and 50 neonates (77%) had associated cardiovascular anomalies (ie, aortic annular hypoplasia, hypoplasia of the left ventricle, mitral valve abnormalities, and endocardial fibroelastosis, coarctation, or interruption of aorta).
Results: The hospital mortality was 29% (19 of 66). Kaplan-Meier 5- and 15-year survival was 61% and 58%, respectively. The operative mortality rates were 6% in neonates with isolated AS and 36% in patients with complex AS. The five risk factors significant for mortality on univariate analysis were (1) presence of endocardial fibroelastosis (p = 0.05), (2) presence of hypoplastic left ventricle (p = 0.003), (3) presence of associated cardiovascular anomalies (p = 0.04), (4) aortic valve annulus of less than 5.0 mm (p = 0.01), and (5) surgery before 1985 (p = 0.003). Of these five factors, only the presence of hypoplastic left ventricle (p = 0.001) and surgery before 1985 (p = 0.001) remain significant for mortality by multivariate analysis. At last follow-up (mean, 8.2 +/- 6.2 years), 36 of 47 of the long-term survivors were in New York Heart Association functional class I and II. Kaplan-Meier analysis showed 5- and 15-year freedom from aortic valve reoperation to be 83% and 60%, respectively. Univariate and multivariate analysis showed the presence of multilevel stenosis (p = 0.04) as the best preoperative predictor for the need for late reoperation in survivors.
Conclusions: We conclude that critical AS in neonates continues to be associated with significant mortality. Reintervention such as surgical and balloon valvotomy are usually required within 10 years of initial surgery.