Predictors for Regression of Large Secundum Atrial Septal Defects Diagnosed in Infancy

Area of Science:

• Pediatric Cardiology
• Congenital Heart Disease
• Echocardiography

Background:

• Large secundum atrial septal defects (ASDs) diagnosed in infancy represent a significant congenital heart condition.
• Understanding the natural course and predictors of spontaneous closure or size reduction is crucial for clinical management.
• Previous studies have focused on smaller defects or interventions, leaving a gap in knowledge for large defects in infancy.

Purpose of the Study:

• To identify predictive factors for spontaneous closure or size reduction in large secundum-type atrial septal defects (ASDs) diagnosed in infancy.
• To differentiate between infants with favorable outcomes (closure or significant size reduction) and those with persistent large defects.
• To inform non-invasive management strategies for large ASDs in the pediatric population.

Main Methods:

• Retrospective enrollment of 59 infants diagnosed with secundum-type ASDs ≥ 8 mm in the first year of life (June 2003-October 2009).
• Review of medical records, electrocardiography, and echocardiography findings.
• Classification into two groups: Group A (n=23) with ASD size < 5 mm or spontaneous closure, and Group B (n=36) with ASD size ≥ 5 mm.

Main Results:

• Spontaneous closure occurred in 17% of patients, with size reduction to < 5 mm in 22%.
• Younger age at diagnosis was a significant predictor (p=0.014) for favorable outcomes.
• An initial ASD diameter of ≥ 10 mm was a negative predictor for size reduction (p=0.017), while better weight gain at 6 months was associated with favorable changes (p=0.01).

Conclusions:

• Spontaneous closure or size reduction of large secundum-type ASDs is common in infants.
• Favorable outcomes are more likely in infants with initial ASD sizes between 8-10 mm, younger age at diagnosis, and improved weight gain.
• These findings support expectant management for select large ASDs diagnosed in infancy.