What is atrial septal defect (ASD) management?

Atrial Septal Defect Management

Closure of an ASD either percutaneously or surgically is indicated for right atrial and RV enlargement with or without symptoms, with percutaneous closure preferred for secundum ASDs with suitable anatomy and surgical repair required for other ASD types. 1

Diagnosis and Evaluation

• Imaging confirmation required: ASD should be diagnosed by imaging techniques demonstrating shunting across the defect and evidence of RV volume overload 1

• Key diagnostic tests:

  • Transthoracic echocardiography: First-line assessment of defect size, location, and right heart enlargement
  • Transesophageal echocardiography: Better visualization of atrial septum and pulmonary venous connections
  • Pulse oximetry: At rest and with exercise to assess shunt direction 1
  • Cardiac MRI or CT: For delineating pulmonary venous connections in complex cases 2

• Exercise testing: Useful for patients with symptoms discrepant with clinical findings or to document oxygen saturation changes with mild/moderate PAH (Class IIa) 1

• Cardiac catheterization: Useful to rule out concomitant coronary artery disease in patients at risk (Class IIa) 1

Types of ASDs

• Secundum ASD: Most common (90%), located in fossa ovalis region
• Primum ASD: Located inferiorly near the crux of the heart
• Sinus venosus ASD: Located near superior or inferior vena caval entry
• Coronary sinus septal defect: Uncommon, causes shunting through coronary sinus ostium 1

Indications for Closure

Class I Recommendations (Strong)

• Right atrial and RV enlargement with or without symptoms 1
• Sinus venosus, coronary sinus, or primum ASD (surgical repair required) 1

Class IIa Recommendations (Reasonable)

• Paradoxical embolism
• Documented orthodeoxia-platypnea
• When concomitant tricuspid valve repair/replacement is needed 1
• When net left-to-right shunt (Qp:Qs) is ≥1.5:1 without cyanosis at rest or during exercise 1

Class IIb Recommendations (May Consider)

• When net left-to-right shunt (Qp:Qs) is ≥1.5:1 with PA systolic pressure ≥50% of systemic pressure and/or pulmonary vascular resistance >1/3 systemic resistance 1

Contraindications (Class III: Harm)

• PA systolic pressure >2/3 systemic
• Pulmonary vascular resistance >2/3 systemic
• Net right-to-left shunt 1

Closure Methods

Percutaneous Closure

• Preferred for: Secundum ASDs with suitable anatomy 2
• Device options:
  • Amplatzer Septal Occluder: Most commonly used 3
  • Gore HELEX: Useful for small to medium-sized defects
  • Amplatzer Cribriform: Used for fenestrated ASDs 2, 3
• Benefits: Decreased hospital stay, avoidance of sternotomy, lower cost, more rapid recovery 3, 4
• Outcomes: Rapid improvement in right heart morphology within one month of closure 5

Surgical Repair

• Required for:
  • Sinus venosus, coronary sinus, or primum ASDs
  • Large secundum ASDs (>38mm)
  • Defects with deficient rims
  • When concomitant procedures are needed 1, 2
• Techniques: Pericardial patch closure or direct suture closure 2, 6
• Approaches: Traditional sternotomy or minimally invasive (ministernotomy, thoracoscopic) 2, 6

Follow-up and Monitoring

• Regular follow-up: Annual clinical follow-up for patients with persistent/residual pulmonary hypertension, atrial arrhythmias, RV/LV dysfunction 2
• Echocardiogram: Every 2-3 years to assess RV size and function and pulmonary pressure in patients with small unclosed ASDs 1
• Device evaluation: At 3 months to 1 year after closure and periodically thereafter 2

Complications and Management

• Atrial arrhythmias: Should be treated to restore and maintain sinus rhythm; anticoagulation recommended for atrial fibrillation 1
• Device-related: Monitor for thrombosis, cardiac erosion, arrhythmias, nickel allergy, conduction abnormalities 2
• Surgical complications: Postpericardiotomy syndrome, atrial arrhythmias, SVC stenosis, pulmonary vein stenosis 2

Outcomes

• Early closure (before age 25) is associated with better outcomes and normal life expectancy 2, 7
• Closure in adults still improves morbidity and survival but may be associated with new or recurrent atrial arrhythmias 1, 2
• Right ventricular remodeling occurs rapidly after closure, with significant improvement in right heart dimensions and function 5

Special Considerations

• Small ASDs: Patients with small shunts and normal RV size are generally asymptomatic and require no immediate intervention but should be monitored 1
• Elderly patients: Still benefit from closure despite higher risk of persistent arrhythmias 1, 2
• Borderline PAH cases: Test occlusion with hemodynamic measurements can help determine closure candidacy 2