Pediatric Atrial Septal Defects Treatment & Management

Medical therapy is of no benefit in children with asymptomatic atrial septal defects (ASDs). With the exception of ostium secundum types, atrial septal defects are structural defects that do not spontaneously close. Surgical closure is ultimately required for most atrial septal defects, other than ostium secundum atrial septal defects. An ostium secundum atrial septal defect that measures 6 mm in diameter or smaller in the patient's first year of life is likely to spontaneously close; however, such closure is substantially slower than that of a typical small, muscular ventricular septal defect.

Infants who are severely affected with an atrial septal defect and who develop congestive heart failure (CHF) may be treated as any other child with CHF from a left-to-right shunt. This treatment, which includes diuretics, digoxin, and afterload reduction, is covered in other articles.

Arrhythmias associated with atrial septal defect are similarly uncommon in childhood but have become increasingly common with age. In fact, the development of atrial fibrillation may trigger CHF in adults with atrial septal defect who are younger than 40 years. Arrhythmias may result from atrial distention, and these individuals may require antiarrhythmic therapy until the atrial septal defect is repaired.

Some children with an atrial septal defect present with recurrent respiratory tract infections, which may be poorly tolerated. If immunologically normal, these children are not at a higher risk for infection in general, but the chronically increased pulmonary bloodflow, when combined with the inflammatory changes associated with lower respiratory tract infections, can lead to prolonged symptoms and altered cardiopulmonary interactions.

Bacterial endocarditis prophylaxis is not necessary for the typical patient with an isolated atrial septal defect, regardless of the type of atrial septal defect. Prophylaxis is recommended prior to surgical repair if the atrial septal defect is part of complex cyanotic congenital heart disease (CHD). Endocarditis prophylaxis is recommended for 6 months following either surgical or percutaneous repair of atrial septal defects and, in some instances, may be recommended for longer in patients with residual mitral valve abnormalities after surgical repair of primum atrial septal defects. For more information see Antibiotic Prophylactic Regimens for Endocarditis.

Definitive therapy for an atrial septal defect has historically been limited to surgical closure. However, with the advent of transcatheter techniques, many children undergo successful treatment in the cardiac catheterization laboratory.

The most common surgical approach to the defect is primary repair with suture closure or with patch repair (generally with glutaraldehyde treated autologous pericardium or fabric made of polyester fiber [Dacron]).

Not all children with an atrial septal defect are candidates for surgery, which is only indicated for those children with clinically significant left-to-right shunting. In general, a pulmonary-to-systemic flow ratio of 1.5:1 or more is considered the principal indication for surgical repair. Shunting less than this in children with small defects and in those with existing pulmonary hypertension may be observed. Because cardiac catheterization is rarely necessary, echocardiographic evidence of right atrial and right ventricular enlargement is usually considered evidence of a clinically significant left-to-right shunt and an indication for surgical closure of the atrial septal defect.

Surgery is ideally performed in children aged 2-4 years and has a low mortality rate. However, surgery may be performed earlier than this if the child has evidence of CHF.

Newer, minimally-invasive surgical techniques have been developed. These improve cosmetic appearances and decrease hospital stays. These techniques are ideally suited for simple closure of a secundum atrial septal defect.

The surgical mortality rate is low in patients with uncomplicated atrial septal defects. In an experienced pediatric center, the mortality rate should be less than 1%.

Postoperative morbidity in individuals with atrial septal defects is almost exclusively due to accumulation of pericardial fluid (postpericardiotomy syndrome), which occurs in approximately one third of patients. On occasion, tamponade occurs and requires pericardiocentesis. Pericardial effusion should be suspected in any pediatric patient who undergoes postsurgical repair of an atrial septal defect and who presents with chest pain, fever, shortness of breath, or general malaise. In young children, symptoms may be nonspecific and include irritability and decreased appetite.

Transcatheter approaches to atrial septal defect closure have gained acceptance in the pediatric population. Secundum atrial septal defects are currently the only subtype of atrial septal defect that are amenable to this approach.

Such techniques require individuals with considerable expertise in the field of interventional pediatric cardiology and cooperation between the interventionalist and the noninvasive imaging specialists.

Benefits of the transcatheter approach include its minimal invasiveness, the lack of median sternotomy, the avoidance of cardiopulmonary bypass, and the relatively quick recovery time. Potential drawbacks and concerns include residual shunting around the device, embolization during placement requiring surgical intervention, lack of adequate septal rims to properly seat the device and the need for specific technical expertise and equipment. Long-term safety concerns are noted because device placement in smaller children is still relatively new. Transcatheter approaches for atrial septal defect closure are becoming prevalent, and studies are showing a high success rate.

Diagnosis of an atrial septal defect in a newborn or an older child should prompt consultation with a pediatric cardiologist.

Almost all newborns have a small left-to-right shunt at the foramen ovale, as detected during echocardiography in the neonatal period. In the absence of a murmur or other signs of a true atrial septal defect on subsequent well-child care visits, consultation with a cardiologist is probably not necessary, although review of the initial echocardiogram report is prudent to verify the description of the defect.

Children with atrial septal defects generally have no restrictions on their activity. Children with compensated CHF with an atrial septal defect are candidates for surgical or catheter-based intervention and should be able to resume normal activity after the defect is corrected.