What is the recommended evaluation and management for children with a ventricular septal defect based on defect size, symptoms, and evidence of left‑to‑right shunt, ventricular overload, or pulmonary hypertension?

Management of Children with Ventricular Septal Defect

Initial Evaluation Strategy

Echocardiography is the key diagnostic technique and should be performed in all children with suspected VSD to determine defect size, location, shunt magnitude, left ventricular volume overload, and pulmonary artery pressure 1.

Essential Echocardiographic Parameters to Assess

• Defect size and location (perimembranous, muscular, supracristal/outlet, or inlet) 1
• Left ventricular volume overload as the primary indicator of hemodynamic significance 1
• Pulmonary artery pressure estimation via tricuspid regurgitation velocity 1
• Aortic valve morphology to detect prolapse (particularly with supracristal VSDs) 1
• Right ventricular size and function 1
• Shunt quantification using LA/Ao ratio or Qp:Qs calculation 2

When Additional Imaging is Required

• Cardiac MRI should be obtained when echocardiography provides insufficient visualization, particularly for quantifying LV volume overload and precise shunt calculation 1
• Cardiac catheterization is mandatory when pulmonary hypertension is suspected on echocardiography to measure pulmonary vascular resistance before any intervention 1, 3

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Management Algorithm Based on Defect Size and Hemodynamics

Small VSDs (Restrictive, No LV Volume Overload)

Conservative management with surveillance is appropriate for small restrictive VSDs with normal pulmonary pressures, as they demonstrate 96% survival at 25 years without intervention 4.

Surveillance Protocol

• Clinical follow-up every 1-3 years with physical examination, ECG, and echocardiography 1, 4
• Monitor for complications: endocarditis (occurs in 2 per 1000 patient-years, six times higher than normal population), progressive shunt increase from rising LV pressures, development of double-chambered RV (13% incidence), aortic valve prolapse/regurgitation, and discrete subaortic stenosis 1, 5, 4
• Endocarditis prophylaxis is required for all unrepaired VSDs 5
• No surgical intervention needed as long as left-to-right shunt remains <50%, LV volume overload is absent, PAP is normal, and no VSD-related aortic regurgitation or symptoms develop 6

Expected Natural History

• Spontaneous closure occurs in approximately 6% of small VSDs followed into adulthood, though closure is unlikely after age 2 years 3, 6
• Event-free survival is 95.5% at 8 years for well-selected patients with small defects 6
• 94.6% remain asymptomatic at long-term follow-up 6

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Moderate to Large VSDs (With LV Volume Overload)

Surgical closure is definitively indicated when there is evidence of left ventricular volume overload with Qp:Qs ≥1.5:1, provided pulmonary artery systolic pressure is <50% of systemic pressure and pulmonary vascular resistance is <1/3 systemic resistance 3.

Additional Indications for Closure

• Symptomatic heart failure attributable to left-to-right shunting without severe pulmonary vascular disease 4
• History of infective endocarditis caused by the VSD 4
• Progressive aortic regurgitation from VSD-associated aortic valve prolapse 4
• Development of double-chambered right ventricle causing obstruction 4

Critical Pre-Operative Assessment

Closure must not be performed if 3:

• Pulmonary artery systolic pressure is >2/3 systemic
• Pulmonary vascular resistance is >2/3 systemic
• Net right-to-left shunt is present
• Eisenmenger syndrome has developed

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Surgical vs. Device Closure Decision

Surgical Closure (Preferred for Most VSDs)

All VSD closures should be performed by surgeons with training and expertise in congenital heart disease through a right atrial approach using cardiopulmonary bypass with patch closure 3.

Indications for Surgical Approach

• Perimembranous VSDs (most common type) due to risks of aortic valve prolapse and aortic regurgitation 3
• Supracristal/outlet VSDs due to substantial risk of aortic valve prolapse 1
• Inlet VSDs 7
• VSDs with prolapsed aortic valve leaflets 7

Device Closure (Limited Indications)

Transcatheter device occlusion with the Amplatzer Muscular VSD Occluder is the preferred approach for muscular VSDs that are remote from the tricuspid valve and aorta 4, 7.

Critical Contraindication

Device closure of perimembranous VSDs with the Amplatzer Membranous VSD Occluder is not recommended due to notable risk of inducing complete heart block 7.

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Special Populations and Circumstances

Large Nonrestrictive VSDs in Infancy

• 62% demonstrate partial closure during serial catheterizations in the first year of life 8
• Pulmonary vascular resistance rises in 21% of patients with large VSDs before surgery 8
• Surgery is necessary in 51% of nonrestrictive VSDs versus only 12% of large-restrictive VSDs in infancy 8
• Without surgery, approximately 50% develop Eisenmenger syndrome, though this typically takes years 3

Eisenmenger Syndrome (Absolute Contraindication to Closure)

VSD closure must be avoided in patients with Eisenmenger physiology, characterized by severe pulmonary vascular disease with shunt reversal (right-to-left shunt) and cyanosis 1, 4.

• These patients require specialized management in grown-up congenital heart disease (GUCH) centers 1
• Pregnancy is contraindicated due to excessive maternal and fetal mortality 4
• Strenuous exercise and travel to altitudes >5000 feet should be avoided 4

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Post-Operative Follow-Up

Patients Repaired Before Age 25 Without Residual Defects

Do not require regular follow-up if there is no residual shunt, normal PAP, normal RV, and no arrhythmias 1.

However, patients and referring physicians should be informed about possible late occurrence of tachyarrhythmias 1.

Patients Requiring Ongoing Surveillance

Annual follow-up at a congenital heart disease center is required for 4, 3:

• Residual heart failure
• Residual shunts
• Pulmonary arterial hypertension
• Aortic or tricuspid regurgitation
• RV or LV outflow tract obstruction
• Patients repaired at adult age (particularly >40 years) 1

Surveillance Echocardiography Should Assess

• Residual shunt 1, 3
• Development of aortic or tricuspid regurgitation 4
• Left ventricular function and volume overload 4
• Pulmonary artery pressure 4
• Development of double-chambered right ventricle 4
• Development of discrete subaortic stenosis 4
• RV size and function 1

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Common Pitfalls to Avoid

• Do not delay surgery once indication is established, as progressive LV volume overload and pulmonary vascular changes can occur 3
• Do not use device closure for perimembranous VSDs due to heart block risk 7
• Do not assume small VSDs are benign—they carry six-fold increased endocarditis risk and can progress over time 5
• Do not miss outlet/supracristal VSDs, which have substantial risk for aortic valve prolapse requiring earlier intervention 1
• Do not perform catheterization routinely—reserve for cases with suspected pulmonary hypertension on echo 1, 3