Most Common Congenital Heart Disease in Children
Ventricular septal defect (VSD) is the most common congenital heart defect at birth, occurring in approximately 3.0 to 3.5 per 1000 live births and accounting for 30-40% of all congenital heart malformations in children. 1, 2, 3
Epidemiology and Prevalence
VSD represents the single most prevalent congenital cardiac malformation when diagnosed at birth, surpassing all other major defects including atrial septal defects, transposition of the great arteries, tetralogy of Fallot, and aortic coarctation 2, 3
Population-based cohort data demonstrates that 3.3% of unselected newborns have a VSD identified on echocardiographic screening 4
The prevalence decreases dramatically during the first year of life, with 83.5% of VSDs closing spontaneously by age 12 months, reducing prevalence to 0.5% in one-year-old children 4
Important Clinical Context: Birth vs. Adulthood
In adults, bicuspid aortic valve becomes the most common congenital heart anomaly, followed by atrial septal defect, because many VSDs close spontaneously during childhood 2
Muscular VSDs demonstrate significantly higher spontaneous closure rates (86.9%) compared to perimembranous VSDs (46.9%) during the first year of life 4
Smaller VSD size and absence of multiple defects are the primary determinants associated with spontaneous closure 4
Anatomic Classification
Perimembranous VSDs (Type 2) account for approximately 80% of all ventricular septal defects, making them the most common subtype 2, 3
Muscular VSDs represent 92.6% of VSDs identified in newborn screening studies, though many close spontaneously 4
Subarterial/outlet VSDs (Type 1) occur in 6% of non-Asian populations but up to 33% in Asian patients 2, 3
Inlet VSDs (Type 3) are commonly associated with Down syndrome 2, 3
Clinical Significance and Prognosis
Children with isolated VSDs have a favorable prognosis without excess mortality compared to children without VSDs (adjusted HR 0.8, p=0.48) 5
Cardiac complications requiring hospitalization or intervention during childhood are infrequent: endocarditis in 0.9‰, aortic regurgitation in 3.4‰, pulmonary hypertension in 0.3‰, and arrhythmias in 4.6‰ 5
Only 5.2% of children with isolated VSDs require surgical or catheter-based treatment 5
Operative mortality is essentially zero in contemporary series of isolated VSD repair 5
Common Pitfalls
Do not assume all VSDs require intervention—the vast majority close spontaneously or remain hemodynamically insignificant 5, 4
Recognize that genetic syndromes (Down syndrome, 22q11.2 deletion) are frequently associated with VSDs and require comprehensive evaluation beyond the cardiac defect 1
In complex congenital heart disease requiring neonatal surgery (hypoplastic left heart syndrome, interrupted aortic arch, truncus arteriosus), VSDs are components of more severe lesions that carry high risk for neurodevelopmental disabilities 1