Echocardiographic predictors of surgical outcomes in pulmonary atresia with intact ventricular septum and development of a discriminatory calculator: an Australian tertiary institution experience

Introduction: Pulmonary atresia with intact ventricular septum is a rare congenital cardiac lesion with significant anatomical heterogeneity. Surgical planning of borderline cases remains challenging and is primarily based on echocardiography. The aim was to identify echocardiographic parameters that correlate with surgical outcome and to develop a discriminatory calculator.

Methods: Retrospective review of all pulmonary atresia with intact ventricular septum cases at a statewide tertiary paediatric cardiac centre was performed between 2004 and 2020. Demographic, clinical, and echocardiographic data were collected. Logistic regression was used to develop a discriminatory tool for prediction of biventricular repair.

Results: Forty patients were included. Overall mortality was 27.5% (n = 11) and confined to patients managed as univentricular (11 vs 0, p = 0.027). Patients who underwent univentricular palliation were more likely to have an associated coronary artery abnormality (17 vs 3, p = 0.001). Fifteen surviving patients (51.7%) achieved biventricular circulation while 14 (48.3%) required one-and-a-half or univentricular palliation. Nineteen patients (47.5%) underwent percutaneous pulmonary valve perforation. No patients without tricuspid regurgitation achieved biventricular repair. The combination of tricuspid valve/mitral valve annulus dimension ratio and right ventricle/left ventricle length ratio identified biventricular management with a sensitivity of 93% and specificity of 96%. An online calculator has been made available.

Conclusion: Pulmonary atresia with intact ventricular septum is a challenging condition with significant early and interstage morbidity and mortality risk. Patient outcomes were comparable to internationally reported data. Right ventricle/left ventricle length and tricuspid valve/mitral valve annulus dimension ratios identified a biventricular pathway with a high level of sensitivity and specificity. Absent tricuspid regurgitation was associated with a univentricular outcome.