From the Guidelines
Atrial Septal Defect (ASD) is a common congenital heart defect in babies, and small ASDs are considered normal, but they require monitoring to determine if spontaneous closure occurs or if medical intervention is necessary. ASDs occur in approximately 1 in 1,500 births, and most small ASDs (less than 8mm) close spontaneously by age 2 without intervention, through natural tissue growth as the heart develops 1. For larger ASDs that don't close on their own, medical intervention may be necessary.
Treatment Options
Treatment options include:
- Catheter-based closure using an occluder device, which is minimally invasive
- Surgical repair for larger defects The closure mechanism involves tissue growth around the defect or device, eventually creating a complete seal. Regular monitoring by a pediatric cardiologist is essential for babies with ASDs to track whether spontaneous closure occurs or if intervention becomes necessary.
Importance of Closure
The timing of closure is important because untreated significant ASDs can lead to complications like pulmonary hypertension or heart failure later in life. According to the ACC/AHA 2008 guidelines, small ASDs with a diameter of less than 5 mm and no evidence of RV volume overload do not impact the natural history of the individual and thus may not require closure unless associated with paradoxical embolism 1. Larger defects with evidence of RV volume overload on echocardiography usually only cause symptoms in the third decade of life, and closure is usually indicated to prevent long-term complications.
Closure Methods
The majority of secundum ASDs can be closed with a percutaneous catheter technique, and when this is not feasible or is not appropriate, surgical closure is recommended 1. Sinus venosus, coronary sinus, and primum defects are not amenable to device closure. An ASD with a large septal aneurysm or a multifenestrated atrial septum requires careful evaluation by and consultation with interventional cardiologists before device closure is selected as the method of repair.
From the Research
Atrial Septal Defect (ASD) in Babies
- ASD is a common congenital heart defect, which can be present in babies 2, 3, 4.
- It is characterized by an opening in the interatrial septum, allowing blood to flow between the left and right atria 5.
Closure of ASD
- Small defects may spontaneously close, while larger defects may require percutaneous or surgical intervention 2, 5.
- The timing of repair depends on patient age, symptomatology, and the presence of associated anomalies 2.
- Percutaneous closure is a preferred method for secundum ASD, with a success rate of over 98% and low complication rates 6.
- Surgical closure is also safe and effective, and when done before age 25 years, is associated with normal life expectancy 4.