Do all Ventricular Septal Defects (VSDs) require correction?

Not All VSDs Require Correction

The statement that all VSDs should be corrected is false—small restrictive VSDs without left ventricular volume overload, pulmonary hypertension, or complications should be managed conservatively with surveillance only. 1

VSDs That Do NOT Require Closure

Small Restrictive VSDs

• Small defects (VSD <1.0 cm) with Qp:Qs <1.5:1, no LV volume overload, and normal pulmonary pressures should be observed without surgical intervention 1
• These patients demonstrate excellent long-term outcomes with 96% survival at 25 years without intervention 1
• Surgery should be avoided if the VSD is small, not subarterial, does not lead to LV volume overload or pulmonary hypertension, and there is no history of infective endocarditis 1

Asymptomatic Patients Without Hemodynamic Consequences

• Asymptomatic patients without evidence of LV volume overload should not undergo surgery, even with Qp:Qs ratios >1.5:1 2
• The absence of symptoms combined with normal LV dimensions and normal pulmonary pressures indicates conservative management with surveillance every 3-5 years is appropriate 2

VSDs That REQUIRE Closure

Hemodynamically Significant Shunts

• Closure is indicated for symptomatic patients with heart failure attributable to left-to-right shunting when there is no severe pulmonary vascular disease 1
• Asymptomatic patients with evidence of LV volume overload attributable to the VSD should undergo closure 1
• Closure is recommended when Qp:Qs ≥1.5:1 with LV volume overload, provided PA systolic pressure is <50% systemic and pulmonary vascular resistance is <1/3 systemic 1, 2

Specific Complications

• Patients with VSD-associated aortic valve cusp prolapse causing progressive aortic regurgitation should be considered for surgery 1
• This occurs in approximately 6% of patients with supracristal or perimembranous VSDs 1, 2
• Patients with a history of infective endocarditis caused by the VSD should be considered for surgical closure 1
• The risk of IE in unoperated small VSDs is 1.7-2.7 per 1000 patient-years, which is 20-30 times higher than the general population 3

Pulmonary Hypertension with Preserved Shunt Direction

• Patients with VSD and pulmonary hypertension should be considered for surgery when there is still net left-to-right shunt (Qp:Qs >1.5) and PAP or pulmonary vascular resistance are <2/3 of systemic values 1
• Fenestrated devices or surgical patches may be used in select cases to allow right heart decompression 1

Absolute Contraindications to Closure

Eisenmenger Syndrome

• Surgery must be avoided in Eisenmenger VSD and when exercise-induced desaturation is present 1, 2
• Closure of nonrestrictive VSD in adults with Eisenmenger syndrome who do not demonstrate left-to-right shunting carries a high risk of mortality and should not be performed 1
• Pregnancy is contraindicated in Eisenmenger syndrome 1

Severe Pulmonary Vascular Disease

• Patients with severe pulmonary vascular disease without reversible shunting should not undergo closure 1

Natural History Considerations

Spontaneous Closure Rates

• Many VSDs decrease in size over time, particularly in infancy 4
• Seventy-five percent of patients with moderate VSDs do not require surgery, and 58% have normal pulmonary artery pressures on follow-up catheterization 4
• Of patients with large-restrictive VSDs, 62% had partial closure and only 12% required surgery in infancy 4

Long-Term Complications Requiring Surveillance

• Development of double-chambered right ventricle (DCRV) can occur over time from the high-velocity VSD jet 1, 2
• Discrete subaortic stenosis can develop, though this is rare 1
• Arrhythmias occur but are less frequent than in other forms of congenital heart disease 1
• Complete heart block is rare in modern surgical series but can occur in older patients from earlier surgical eras 1

Follow-Up Protocols

Conservative Management

• Patients with small VSDs, normal LV function, and normal pulmonary pressures can be followed at 3-5 year intervals 1, 2
• Surveillance should assess for development of aortic or tricuspid regurgitation, LV volume overload, pulmonary artery pressure elevation, DCRV, and discrete subaortic stenosis 2

Post-Intervention Surveillance

• Annual follow-up is required for patients with residual heart failure, residual shunts, pulmonary arterial hypertension, aortic regurgitation, or RV/LV outflow tract obstruction 1, 2
• After device closure, regular follow-up during the first 2 years and then every 2-4 years is recommended 1

Critical Pitfalls to Avoid

• Do not confuse the high gradient across a small restrictive VSD (which may exceed 100 mmHg) with an indication for closure—this gradient reflects the restrictive nature of the defect, not hemodynamic significance 2
• Do not overlook the development of aortic valve prolapse in perimembranous and supracristal VSDs, which requires intervention even when the VSD itself is small 1, 2
• Avoid misdiagnosing heart failure as pneumonia in infants with VSD presenting with respiratory symptoms 5
• Do not assume all patients with Qp:Qs >1.5:1 require closure—LV volume overload must be present in asymptomatic patients to justify intervention 2

Special Populations

Pregnancy

• Small perimembranous VSDs without left heart dilatation have a low risk of complications during pregnancy 1
• Usually follow-up twice during pregnancy is sufficient, and spontaneous vaginal delivery is appropriate 1
• Corrected VSDs have a good prognosis during pregnancy when LV function is preserved 1