What are the indications for intervention in a patient with a Ventricular Septal Defect (VSD)?

Indications for Intervention in Ventricular Septal Defect (VSD)

Surgical or device closure of a VSD is strongly indicated when there is a pulmonary-to-systemic blood flow ratio (Qp:Qs) of 2.0 or greater with clinical evidence of left ventricular volume overload. 1

Primary Indications for VSD Closure

Class I Indications (Strongly Recommended)

• Qp:Qs ≥2.0 with evidence of LV volume overload 1
• History of infective endocarditis 1
• Pulmonary artery systolic pressure <50% systemic and pulmonary vascular resistance <1/3 systemic 1

Class IIa Indications (Reasonable to Perform)

• Qp:Qs >1.5 with pulmonary artery pressure <2/3 systemic and pulmonary vascular resistance <2/3 systemic 1
• Qp:Qs >1.5 with LV systolic or diastolic failure 1
• Worsening aortic regurgitation caused by VSD (particularly perimembranous or supracristal VSDs) 1

Class IIb Indications (May Be Considered)

• Qp:Qs ≥1.5 when pulmonary artery systolic pressure is ≥50% systemic and/or pulmonary vascular resistance is >1/3 systemic 1
• Device closure of muscular VSD, especially if remote from tricuspid valve and aorta, or if associated with severe left-sided heart chamber enlargement 1

Contraindications for VSD Closure

Class III (Harm) - Do Not Perform

• Severe irreversible pulmonary arterial hypertension (PAH) 1
• PA systolic pressure >2/3 systemic 1
• Pulmonary vascular resistance >2/3 systemic 1
• Net right-to-left shunt (Eisenmenger syndrome) 1

Diagnostic Evaluation Before Intervention Decision

1. Echocardiography:

   • Determine size, location, and number of VSDs
   • Assess LV/RV function and chamber size
   • Evaluate for aortic regurgitation
   • Estimate pulmonary artery pressure

2. Cardiac Catheterization (when needed):

   • Accurate measurement of Qp:Qs ratio
   • Direct measurement of pulmonary artery pressure
   • Calculation of pulmonary vascular resistance
   • Assessment of operability in patients with PAH

Follow-up Recommendations After VSD Management

• Adults with residual heart failure, shunts, PAH, aortic regurgitation, or RVOT/LVOT obstruction: Annual follow-up at ACHD center 1
• Adults with small residual VSD and no other lesions: Follow-up every 3-5 years at ACHD center 1
• Adults with device closure: Follow-up every 1-2 years at ACHD center 1
• Adults with no residual VSD, no associated lesions, and normal pulmonary artery pressure: No continued follow-up at regional ACHD center required 1

Special Considerations

• Pregnancy: Contraindicated in patients with VSD and severe PAH (Eisenmenger syndrome) due to excessive maternal and fetal mortality 1
• Small VSDs: Generally have good long-term outcomes without intervention, with 96% event-free survival at 25 years 2, 3
• Residual shunts: Small residual shunts after repair are common (38%) but most (65%) close spontaneously within 10 months 4

Potential Pitfalls in VSD Management

• Failure to recognize associated defects that may manifest only after closure of the dominant VSD
• Mistaking VSD jet for tricuspid regurgitation jet in patients with normal pulmonary pressure
• Failure to recognize right ventricular outflow obstruction associated with VSD
• Inappropriate patient selection for intervention, particularly in borderline cases of pulmonary hypertension

The decision for VSD intervention should be based on careful hemodynamic assessment, with particular attention to the degree of left-to-right shunting, pulmonary artery pressure, and pulmonary vascular resistance. Early intervention is recommended for significant shunts before irreversible pulmonary vascular changes develop.