What are the treatment plans for atrial septal defect (ASD)?

Treatment Plans for Atrial Septal Defect (ASD)

The primary treatment for atrial septal defects is closure, either by percutaneous transcatheter device or surgical repair, with the choice depending on ASD type, size, and associated hemodynamic abnormalities. 1

Assessment and Indications for Closure

Indications for ASD Closure:

• Class I (Strong Recommendation):
  • Right atrial and RV enlargement with or without symptoms 1
  • Qp:Qs ratio ≥1.5:1 (significant left-to-right shunt) 1
  • Prevention of long-term complications:
    • Atrial arrhythmias
    • Reduced exercise tolerance
    • Tricuspid regurgitation
    • Right-to-left shunting during pregnancy
    • Congestive heart failure
    • Pulmonary vascular disease 1

Contraindications for Closure:

• Severe pulmonary arterial hypertension with:
  • PA systolic pressure >2/3 systemic
  • Pulmonary vascular resistance >2/3 systemic
  • Net right-to-left shunt 1

Treatment Algorithm

1. Diagnostic Evaluation:

• TTE to assess defect size, location, and right heart enlargement
• TEE for better visualization of atrial septum and pulmonary venous connections
• CMR or CCT to delineate pulmonary venous connections
• Pulse oximetry at rest and with exercise to assess shunt direction 1

2. Selection of Closure Method:

Transcatheter Device Closure:

• Preferred for:
  • Secundum ASDs with suitable anatomy 2
  • Defects with adequate rims for device anchoring
  • Defects typically <38mm in diameter 3

Surgical Closure:

• Required for:
  • Sinus venosus, coronary sinus, or primum ASDs 1, 2
  • Large secundum ASDs (>38mm) 3
  • Defects with deficient rims 3
  • When concomitant tricuspid valve repair is needed 1
  • Failed transcatheter closure attempts 4

Procedural Details

Transcatheter Closure:

• Performed under general anesthesia with TEE guidance
• Device selection typically 1-2mm larger than measured defect diameter
• Procedural anticoagulation with UFH (100 U/kg)
• Post-procedure aspirin for at least 6 months 2
• Advantages:
  • Avoids cardiopulmonary bypass
  • Shorter hospital stay (average 2.06 days vs 5.56 days for surgery) 4
  • Reduced recovery time
  • No sternotomy scar 5

Surgical Closure:

• Options include:
  • Pericardial patch closure
  • Direct suture closure
  • Minimally invasive approaches (ministernotomy, thoracoscopic)
  • Concomitant Maze procedure for atrial arrhythmias 1
• Early mortality approximately 1% without pulmonary hypertension 1

Post-Procedure Follow-up

Immediate Post-Procedure:

• Monitor for early complications:
  • Pericardial effusion/tamponade
  • Device migration/embolization
  • Arrhythmias 1, 2

Long-term Follow-up:

• Echocardiography at:
  • 24 hours
  • 1 month
  • 6 months
  • Annually thereafter 2
• Annual clinical follow-up for patients with:
  • Pulmonary arterial hypertension
  • Atrial arrhythmias
  • RV or LV dysfunction
  • Coexisting valvular or cardiac lesions 1

Potential Complications

Transcatheter Closure:

• Device thrombosis
• Cardiac erosion
• Atrial arrhythmias (most common)
• Nickel allergy
• Conduction abnormalities
• Device endocarditis 5

Surgical Closure:

• Postpericardiotomy syndrome
• Atrial arrhythmias (may occur de novo after repair)
• Superior vena cava stenosis (after sinus venosus ASD repair)
• Pulmonary vein stenosis 1

Special Considerations

ASD with Arrhythmias:

• For patients with unoperated ASD and arrhythmias:
  • Treat both the arrhythmia and the ASD 1
  • Options include:
    • Catheter ablation of arrhythmia plus ASD closure
    • Surgical closure with concomitant Maze procedure 1

ASD with Pulmonary Hypertension:

• Careful assessment of pulmonary vascular reactivity
• Closure may be considered with:
  • PA pressure <2/3 systemic
  • PVR <2/3 systemic
  • Response to pulmonary vasodilator therapy 1

Outcomes

• Early closure (before age 25) associated with better outcomes and lower incidence of arrhythmias 1
• Closure in adults still improves morbidity and survival but may be associated with new (7%) or recurrent (60%) atrial tachyarrhythmias 1
• Pooled analysis shows improvement in functional status and right ventricular size/function after ASD closure 1

By following this structured approach to ASD management, clinicians can optimize outcomes while minimizing complications in both pediatric and adult patients.