What is the recommended management for a patient with an atrial septal defect (ASD)?

Management of Atrial Septal Defect (ASD)

Closure of an ASD is indicated for patients with right atrial and right ventricular enlargement, with or without symptoms, provided that pulmonary arterial pressure is less than two-thirds of systemic pressure and pulmonary vascular resistance is less than two-thirds of systemic vascular resistance. 1, 2

Types of ASDs and Diagnostic Evaluation

ASDs are classified into four main types:

• Secundum ASD (most common)
• Primum ASD
• Sinus venosus ASD
• Coronary sinus ASD

Diagnostic Approach

1. Transthoracic echocardiography (TTE): First-line imaging to assess:

   • ASD size and location
   • Right heart enlargement
   • Estimated pulmonary pressures
   • Shunt magnitude (Qp:Qs ratio) 2

2. Transesophageal echocardiography (TEE): Indicated when TTE is inadequate, especially for:

   • Superior sinus venosus defects
   • Anomalous pulmonary venous connections
   • Detailed atrial septal anatomy 2

3. Cardiac catheterization: Recommended when pulmonary hypertension is suspected 2

Indications for ASD Closure

ASD closure is recommended in the following scenarios:

• Right atrial and RV enlargement (with or without symptoms) 1, 2
• Qp:Qs ratio ≥1.5:1 2
• Paradoxical embolism 1, 2
• Documented orthodeoxia-platypnea (positional desaturation) 1, 2

Closure Methods

Percutaneous Device Closure

• Preferred for: Secundum ASD with adequate rims for device anchoring 1, 2, 3
• Benefits: Shorter hospital stay, avoidance of sternotomy, lower cost, and more rapid recovery 3, 4
• Devices: Amplatzer® Septal Occluder (most common), Amplatzer® Cribriform device (for fenestrated ASDs), Gore HELEX® device (for small to medium-sized defects) 3

Surgical Closure

• Indicated for:

  • Sinus venosus, coronary sinus, or primum ASD 1, 2, 3
  • Inadequate rims for device placement 2
  • Large secundum ASD (>38mm) 2
  • Need for concomitant cardiac surgery 1, 2
  • When the anatomy precludes percutaneous closure 1

• Techniques:

  • Pericardial patch closure or direct suture closure
  • Warden procedure for sinus venosus ASD with anomalous pulmonary venous drainage 1
  • Concomitant tricuspid valve repair for significant regurgitation 1

Contraindications to Closure

• Severe irreversible pulmonary arterial hypertension with:

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

• Small ASDs (<5mm) without RV volume overload generally do not require closure unless associated with paradoxical embolism 1, 2

Post-Closure Management

1. Monitoring for complications:

   • Device migration/erosion (3 months to 1 year after closure and periodically thereafter) 1
   • Residual shunting
   • Thrombus formation
   • Pericardial effusion 1

2. Arrhythmia management:

   • Treat atrial arrhythmias to restore and maintain sinus rhythm 1
   • Consider anticoagulation for atrial fibrillation 1
   • Consider concomitant Maze procedure for intermittent/chronic atrial fibrillation/flutter 1

3. Antiplatelet therapy:

   • Low-dose aspirin for at least 6 months after device closure 2

4. Follow-up schedule:

   • Echocardiographic follow-up at 24 hours, 1 month, 6 months, 1 year, and regular intervals thereafter 1
   • Annual clinical follow-up for patients with:
     • Pulmonary arterial hypertension
     • Atrial arrhythmias
     • RV or LV dysfunction
     • Coexisting valvular or other cardiac lesions 1

Special Considerations

• Age considerations: While early repair is preferred, ASD closure still provides benefits in older adults with right heart enlargement 2

• Left ventricular dysfunction: Patients with LV dysfunction require careful evaluation before closure due to risk of complications from acute changes in left-sided pressures 5

• Outcomes: Closure of ASD can improve functional class, reduce right ventricular pressure and dimensions, and provide a protective effect on mortality 2

• Complications to watch for:

  • Early postoperative symptoms of fever, fatigue, vomiting, chest pain, or abdominal pain may represent postpericardiotomy syndrome with tamponade 1
  • Device erosion may present with chest pain or syncope and warrants urgent evaluation 1

Comparative Outcomes

Percutaneous closure has been shown to have significantly lower rates of both total complications (6.6% vs 31%) and major complications (1.9% vs 6.8%) compared to surgical closure 4. However, surgical repair remains safe with excellent results for all ASD subtypes 6.