Biventricular strategies for neonatal critical aortic stenosis: high mortality associated with early reintervention

Objective: To characterize the risk of reintervention after biventricular strategies to treat neonatal critical aortic stenosis, and the effect of reintervention on survival.

Methods: In a multi-institutional inception cohort of 139 neonates, the time-related risk of reintervention was analyzed using parametric multiphase competing-risk models and a modulated renewal repeated-events method. The risk factors were identified through multivariate regression and selected with bootstrap resampling for reliability. Univentricular survival predictions were generated using the Congenital Heart Surgeons' Society Univentricular Repair Survival Advantage score.

Results: One half of survivors required reintervention within 3 years. The risk of undergoing early reintervention decreased with successive procedures (P<.0001); however, second (n=27) and third (n=8) reinterventions were associated with a greater late risk of repeat reintervention compared with the index procedure (P=.02). The morphologic risk factors for earlier reintervention included left ventricular dysfunction, fewer aortic cusps, associated subaortic or arch obstruction, and a larger tricuspid annulus. The risk of death did not improve after successive reinterventions. Therefore, the overall survival for those requiring repeated reinterventions was compromised by the cumulative procedural risk of death. The most important risk factor for death after the first reintervention (P<.01) was a shorter interval from the index biventricular procedure, particularly if less than 30 days. Fifteen neonates required reintervention within 30 days of the index biventricular procedure (9 deaths, 60%). For the same 15 neonates, the survival predictions using published models estimated fewer than one half the number deaths with index univentricular repair strategies (4/15, 27%, P=.03).

Conclusions: Success of index biventricular procedures has important survival implications: early reintervention implies a poor prognosis and might reflect incorrect management decisions. The morphologic characteristics can help identify such neonates, and univentricular repair might, instead, be preferable.