Severe pulmonary stenosis and atresia (PS, PAIVS) are cardiac anomalies in which right ventricular (RV) outflow is obstructed. Depending on in utero RV growth in the face of this obstruction, severe PS and PA/IVS may exhibit a spectrum of severity, requiring postnatal interventions including balloon pulmonary valvuloplasty alone, surgical biventricular repair, or staged single-ventricle palliation. Tricuspid valve (TV) size at birth has been shown to predict outcome with a TV Z-score <-3 associated with single-ventricle outcome, but prenatal echocardiographic features that might predict postnatal TV size (and outcome) have not been as well studied.Our objective was to determine whether prenatal TV size or other echo-derived cardiac variables can predict favorable postnatal TV diameter in fetuses with PS and PA/IVS.
We identified all neonates with a fetal diagnosis of PS or PA/IVS seen at our institution between 2001-2010. Fetal and neonatal echocardiograms and medical records were reviewed. Doppler variables were analyzed, and measurements of TV, pulmonary valve, and RV and left ventricular (LV) dimensions were made and Z-scores were generated to normalize for fetal size and gestational age. ROC curves were used to generate area under the curve (AUC) for each of the continuous variables.
AUC was 0.94 for TV/mitral valve ratio, 0.9 for RV/LV length ratio, 0.88 for TV Z-Score, and 0.85 for TV inflow duration as a percentage of the total cardiac cycle. A cutoff value of >0.63 for TV/MV ratio yielded a sensitivity of 78% and specificity of 100% for predicting postnatal TV Z score >−3.
Fetal TV/MV >0.63 predicts favorable TV Z score at birth in patients with PS and PA/IVS. This information may be helpful in prenatal counseling of patients with affected fetuses.
|postnatal TV Z score >−3||postnatal TV Z score <−3|
|GA at Dx (wks)(±SD)||27.1±4.8||29.5±3.8|
|TV/MV Ratio (±SD)||0.74±0.2||0.40±0.2|
|TV Z-Score (±SD)||−2.3±1.8||−6.5±2.8|
|TV Inflow Duration (±SD)||0.37±0.06||0.27±0.09|
|RV/LV Length Ratio (±SD)||0.72±0.2||0.38±0.1|
|Forward Flow across Pulmonary valve||5||0|
|Monophasic TV inflow||1||4|
|Abnormal Venous Dopplers||5||5|
|Retrograde Ductus Arteriosus Flow||7||6|
P<0.05, neonatal Z >−3 versus Z<−3
© 2011 Mosby, Inc. Published by Elsevier Inc. All rights reserved.