What is the treatment for muscular Ventricular Septal Defect (VSD)?

Treatment of Muscular Ventricular Septal Defect

For muscular VSDs, catheter closure is the preferred treatment approach beyond infancy, while surgical closure remains the gold standard for infants and complex cases, with specific intervention indicated when there is hemodynamically significant left-to-right shunting (Qp:Qs ≥1.5:1) with left ventricular volume overload. 1

Indications for Intervention in Muscular VSD

Closure is recommended when:

• Hemodynamically significant left-to-right shunt (Qp:Qs ≥1.5:1) with left ventricular volume overload is present, provided pulmonary artery systolic pressure is <50% of systemic pressure and pulmonary vascular resistance is <1/3 systemic resistance 1
• Symptomatic heart failure develops attributable to left-to-right shunting without severe pulmonary vascular disease 1
• History of infective endocarditis caused by the VSD 1
• Left heart volume overload is documented on imaging 2

Catheter closure is specifically mentioned as an interventional option for muscular VSDs in guidelines 2, distinguishing this defect type from perimembranous VSDs where surgical closure remains preferred due to heart block risk.

Treatment Approach by Age and Clinical Context

Beyond Infancy (Preferred: Transcatheter Closure)

• Transcatheter device closure offers excellent results with low morbidity and mortality without requiring cardiopulmonary bypass 3
• This approach avoids the surgical risks associated with bypass in older children and adults 3

Infants (Multiple Surgical Options)

For infants with muscular VSDs, the approach depends on defect location and complexity:

Large mid-muscular VSDs can be treated with:

• Hybrid perventricular closure (preferred for apical/anterior locations) 3
• Surgical closure on cardiopulmonary bypass 3
• Percutaneous approach (though higher adverse event rate in infants) 3

Apical or anterior muscular VSDs:

• Perventricular hybrid closure should be considered as the preferred modality, as these defects are difficult to identify surgically 3
• Left ventriculotomy near the apex provides excellent exposure for surgical closure when hybrid approach is not available 4

Multiple Muscular VSDs

• Single-stage surgical repair through right atrial approach is safe and effective 5
• Completeness of closure should be confirmed by pressurizing the left ventricle with blood cardioplegia 5
• Perventricular device closure is safe and effective for various patient groups, including those with concomitant lesions 6

Conservative Management (Observation)

Small restrictive muscular VSDs (Qp:Qs <1.5:1) with normal pulmonary pressures should be managed conservatively with surveillance, as they have a 96% 25-year survival rate 1

Infrequent follow-up is appropriate unless hemodynamic abnormalities develop 2

Medical Management for Symptomatic Patients

When intervention is not immediately indicated or as bridge therapy:

• ACE inhibitors for patients with chronic heart failure symptoms 1
• Diuretics (furosemide) for volume management and pulmonary congestion 1
• Nitrates for symptom relief in patients without hypotension 1

Absolute Contraindications to Closure

VSD closure must be avoided in:

• Eisenmenger syndrome with exercise-induced desaturation 1, 7
• Severe pulmonary vascular disease (PA systolic pressure >2/3 systemic and pulmonary vascular resistance >2/3 systemic) 7

Follow-Up Protocol

Annual follow-up is required for patients with: 1

• Residual heart failure
• Residual shunts
• Pulmonary arterial hypertension
• Aortic or tricuspid regurgitation
• RV or LV outflow tract obstruction

Surveillance echocardiography should assess: 1

• Development of aortic or tricuspid regurgitation
• Degree of residual shunt
• Left ventricular function and volume overload
• Pulmonary artery pressure
• Development of double-chambered right ventricle
• Development of discrete subaortic stenosis

Critical Pitfalls to Avoid

Surgical technique complications:

• Large patch closure with RV apical exclusion (historically used for "Swiss cheese" multiple muscular VSDs) causes long-term problems including RV diastolic dysfunction, right heart failure, PFO reopening with cyanosis, cirrhosis, and arrhythmias in adult life—this technique should be avoided 8
• Incomplete closure through right atriotomy or right ventriculotomy due to difficult visualization behind hypertrophied trabeculae 4

Diagnostic pitfalls:

• Small muscular VSDs may be mistaken for innocent murmurs; vigilant monitoring for complications is essential 1
• Failure to recognize spontaneous closure potential, as this is frequent in muscular VSDs 2

After device closure, regular follow-up during the first 2 years and then every 2-4 years depending on results is recommended 2