Abstract 15552: Risk Factors for Postnatal Surgery in the Fetus With Borderline Small Left Heart
Background: The presence of mild to moderate hypoplasia of left sided structures in the fetus is commonly observed, but predictors for the need for single ventricle palliation have not been defined.
Objectives: The aim of this study was to evaluate echocardiographic features associated with the need for any postnatal surgery, and specifically for single ventricle palliation in fetuses with mild to moderate aortic valve hypoplasia.
Methods: We reviewed all fetal echocardiograms performed at < 30 weeks gestation demonstrating normal intracardiac relationships and an aortic annulus z-score < -2. Cases were excluded if there was severe mitral hypoplasia (z-score < -4), severe left ventricular hypoplasia as defined by left ventricular end diastolic cross sectional or long axis dimension z-score < -4, mitral atresia, or aortic atresia.
Results: A total of 48 fetuses were identified. Postnatally, 29 underwent cardiac surgery; 12 had aortic arch advancement, 11 had coarctation repair, and 6 required stage I single ventricle palliation. There were 11 postnatal deaths; 4 required stage I palliation prior to death, one would have required stage I palliation but was placed on comfort care, and 6 had significant non-cardiac anomalies who were not surgical candidates. The strongest independent variable associated with outcome was a novel measurement of prenatal aortic valve z-score plus mitral valve z-score (AMZ). An AMZ cutoff of < -6.4 was 83% sensitive and 83% specific for stage I palliation (area under curve = 0.917, p < 0.01), and a cutoff of > -4.4 was 91% sensitive and 80% specific for survival without surgery (area under curve = 0.876, p < 0.01). Fetal retrograde flow in the transverse arch was specific (95%), but less sensitive (60%) for stage I palliation (p < 0.01). Fetal prograde transverse arch flow and right to left flow across the foramen ovale were 100% sensitive for survival without surgery, but only 17% (p = 0.14) and 24% (p = 0.10) specific, respectively.
Conclusion: AMZ is a novel measurement associated with outcomes in fetuses with mild to moderate aortic valve hypoplasia; AMZ scores using cutoffs of -6.4 and -4.4 are useful in predicting stage I palliation and survival without surgery, respectively. AMZ may be helpful in prenatal counseling.
- © 2013 by American Heart Association, Inc.