Abstract 12893: Novel Echocardiographic Logistic Regression Model Predicts Coarctation of the Aorta in the Presence of a Patent Ductus Arteriosus
Background: Diagnosis of Coarctation of the aorta (CoA) in the presence of a patent ductus arteriosus (PDA) is difficult and may require observation off prostaglandin (PG) until PDA closure. The carotid to subclavian index (CSA) and isthmus to descending aorta (I/D) index can help diagnose CoA but have not been validated in neonates requiring observation off PG. The carotid artery to distal transverse arch index (CA/DT) has been used to diagnose CoA prenatally but has not been used in neonates. We evaluated CSA, I/D, and CA/DT indices and developed a novel model to predict neonatal CoA prior to PDA closure.
Methods: A review from 2005-2010 identified: 1) Neonates with PDA and suspicion for CoA with equivocal echocardiograms (n=25) (study group); these neonates required observation off PG to confirm the presence or absence of CoA. 2) Neonates with PDA and a clear diagnosis of either CoA (n=36) or a widely patent aortic arch (n=26) (control group). Four blinded echocardiographers reviewed randomized images of both groups and recorded arch measurements. A logistic regression model was used to predict CoA with pre-specified indices of CA/DT, CSA, and I/D as the predictors.
Results: Only the CSA and CA/DT reached statistical significance in predicting CoA in the study group (p=0.007 and p<0.001); all indices reached statistical significance in the control group (p<0.001). However, all indices had significant overlap in both study (Fig 1A, 1B, 1C) and control groups. The regression model showed clinical significance in predicting CoA using a cut-off of 40% in the study group (Fig 1D) and the control group. The model demonstrated a sensitivity of 100% and specificity of 70% for CoA in the study group and a sensitivity of 89% and specificity of 86% in the control group.
Conclusion: CSA, I/D, and CA/DT alone were not useful to predict CoA in equivocal cases, but a novel model using these indices reliably predicted CoA in the presence of a PDA.
- © 2011 by American Heart Association, Inc.