Pediatrics · Topic 22 of 42
Ventricular Septal Defect (VSD)
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Ventricular Septal Defect (VSD)
The most common congenital heart defect: an opening in the wall between the ventricles shunts blood left to right, so the lungs flood while the infant stays pink. The danger is heart failure from a large defect.
Why it happens
Blood shunts left to right — lungs flooded, infant stays pink
About 42 of every 10,000 US babies are born with a VSD (roughly 16,800 a year).
What you'll see
A large VSD is quiet at birth — heart failure shows by 1–2 months
Heart failure signs often appear by 4–6 weeks, as pulmonary vascular resistance falls after birth and the shunt grows.
Red flags
Treatment
Regular cardiology follow-up instead of surgery
Many small VSDs close by about age 2Care as for infant heart failure
Patch closure on cardiopulmonary bypass
Device closure during cardiac catheterization
Temporary epicardial wires pace heart block or bradycardia
Keep them secured and the pacemaker readyMedicines, timing and long-term risks
Nursing priorities
The conduction pathway runs next to the defect, so the repair can injure it and cause heart block.
Small or large VSD?
Symptoms set the plan — murmur loudness does not show size
| Small VSD | Large VSD | |
|---|---|---|
| Murmur | Can be loud | May be softer |
| Symptoms | Usually none; grows and develops normally | Heart failure: tachypnea, sweaty tiring feeds, poor gain |
| Course | Often closes on its own, usually by about age 2 | Untreated → pulmonary hypertension and Eisenmenger syndrome |
| Plan | Cardiology follow-up; no activity restrictions | Heart failure care, then patch or device repair |
Teach the family
Dental prophylaxis continues past 6 months if a residual leak remains next to the patch. Never teach that every heart defect needs antibiotics before dental work.
A VSD floods the lungs but keeps the infant pink — watch the feeds for heart failure. New cyanosis means the shunt has reversed: report it now.
Sources · About Ventricular Septal Defect (CDC) · Ventricular Septal Defect (MedlinePlus) · Ventricular Septal Defect (Merck Manual Professional) · Critical Arrhythmia in Postoperative Cardiac Children (Ann Pediatr Cardiol) · Ventricular Septal Defect in Children (University Hospitals) · Antibiotic Prophylaxis Prior to Dental Procedures (ADA) · Prevention of Viridans Group Streptococcal Infective Endocarditis (AHA, Circulation 2021) · Follow your facility's protocol for post-operative cardiac monitoring.
Ventricular Septal Defect (VSD)
A ventricular septal defect, or VSD, is an opening in the wall between the heart's ventricles that lets blood shunt left to right, flooding the lungs while the infant stays pink. It is the most common congenital heart defect in children. The hallmark is a loud, harsh holosystolic murmur at the left lower sternal border, though loudness does not show size: a small VSD can be the loudest. A large VSD is usually quiet at birth, then causes heart failure over the first one to two months as pulmonary vascular resistance falls, with fast breathing, sweating and tiring during feeds, poor weight gain and frequent respiratory infections. Left untreated, it leads to pulmonary hypertension and Eisenmenger syndrome, and new cyanosis is a late sign to report at once. Many small VSDs close on their own by about age 2 and need no activity limits. Repair is usually a surgical patch, after which the nurse monitors continuously for heart block. An unrepaired VSD needs no antibiotics before dental work.
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