Most Common Congenital Heart Defect
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. 1
Epidemiology and Context
VSD accounts for approximately 40% of all congenital heart malformations, making it definitively the most prevalent structural cardiac anomaly present at birth 2
VSDs are more frequent than other major congenital heart defects including atrial septal defects, transposition of the great arteries, tetralogy of Fallot, and aortic coarctation 1
Multiple research studies from high-quality journals confirm VSD as the most common congenital cardiac malformation 3, 4, 5
Important Clinical Distinction: Birth vs. Adulthood
A critical caveat exists when considering adults rather than newborns:
In adults, bicuspid aortic valve becomes the most common congenital heart anomaly, followed by atrial septal defect 6
This shift occurs because many VSDs close spontaneously during childhood (particularly muscular VSDs which have high spontaneous closure rates), while bicuspid aortic valves persist throughout life 7, 1
Approximately 10% of patients with common congenital heart defects survive undetected until adulthood 6
Anatomic Classification of VSDs
Perimembranous VSDs (Type 2) represent approximately 80% of all ventricular septal defects, making them the most common subtype 1
Other VSD types include:
- Type 1 (Subarterial/Outlet): 6% in non-Asian populations, up to 33% in Asian patients 1
- Type 3 (Inlet): Commonly associated with Down syndrome 1
- Type 4 (Muscular): Often multiple with high spontaneous closure rates 1
Clinical Significance
Among adults presenting with unrepaired VSDs, manifestations include asymptomatic murmur, infective endocarditis, aortic regurgitation from valve prolapse, or cyanosis with exercise intolerance from pulmonary vascular disease 1
Tetralogy of Fallot, which includes a VSD as one of its four components, is noted as the most common complex congenital defect with the longest surgical history 7