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Echocardiographic Z-Score to Predict Pulmonary-Systemic Flow Ratio in Children With Atrial Septal Defect
Naofumi F Sumitomo1,2, Kazuki Kodo1,3, Jun Maeda2
1Department of Pediatrics, Keio University School of Medicine Tokyo Japan.
Insights
The average right ventricular Z-score (ARV) can non-invasively predict the pulmonary-to-systemic flow ratio (Qp/Qs) in children with atrial septal defect (ASD). This helps determine the need for surgical closure.
Area of Science:
- Pediatric Cardiology
- Echocardiography
- Congenital Heart Disease
Background:
- Atrial septal defect (ASD) is a common congenital heart condition.
- The relationship between right heart enlargement and pulmonary-to-systemic flow ratio (Qp/Qs) in pediatric ASD patients is not fully understood.
- Accurate assessment of Qp/Qs is crucial for guiding treatment decisions.
Purpose of the Study:
- To evaluate echocardiographic Z-scores of the right heart in children with ASD.
- To determine if these Z-scores can predict the pulmonary-to-systemic flow ratio (Qp/Qs).
- To identify a potential non-invasive marker for assessing Qp/Qs in pediatric ASD.
Main Methods:
- Retrospective study of 175 children with isolated ASD.
- Echocardiographic parameters were measured and converted to Z-scores.
- Comparison of echocardiographic Z-scores with cardiac catheterization-derived Qp/Qs (cQp/Qs).
Main Results:
- The average right ventricular Z-score (ARV) showed the strongest correlation with cQp/Qs (r=0.63).
- An ARV cut-off of +2.0 effectively predicted a cQp/Qs ≥1.5 (AUC 0.85).
- Regression-predicted cQp/Qs also correlated well with measured cQp/Qs (r=0.63).
Conclusions:
- The average right ventricular Z-score (ARV) is a reliable non-invasive marker for assessing cQp/Qs in children with ASD.
- ARV can aid in determining the indication for ASD closure.
- Echocardiography offers a valuable tool for risk stratification in pediatric ASD.
Background:
The correlation between pulmonary-to-systemic flow ratio (Qp/Qs) and right heart enlargement in children with atrial septal defect (ASD) remains unclear. This study aimed to (1) assess echocardiographic Z-scores of the right heart, and (2) determine whether they predict Qp/Qs.
Methods And Results:
This retrospective study included 175 children (median age 6.8 years; 68 males) with isolated ASD who underwent cardiac catheterization between 2013 and 2020 at 2 centers in Japan. Patients with genetic anomalies or other conditions affecting right heart size were excluded. Echocardiographic parameters were measured, converted to a Z-score, and compared with the catheterization data. In all patients, the Qp/Qs on cardiac catheterization (cQp/Qs) significantly correlated with the Z-scores of the right ventricular end-diastolic diameter of the basal (RVB), mid-cavity (RVM), and longitudinal length (RVL; r=0.54, 0.57, and 0.52, respectively). The average of these 3 parameters (ARV) showed the strongest correlation (r=0.63). Z-scores of the right atrium, tricuspid valve, and pulmonary artery showed weaker correlations. An ARV cut-off of +2.0 best predicted cQp/Qs ≥1.5 (area under the curve 0.85; 95% confidence interval 0.79-0.92; sensitivity 76.8%; specificity 82.4%). Regression-predicted cQp/Qs also significantly correlated with measured cQp/Qs (r=0.63).
Conclusions:
ARV may be a useful, non-invasive marker for assessing cQp/Qs and determining the indication for closure in children with ASD.
