Ventricular Septal Defect (VSD)
VSD is the most common congenital heart defect in children. It involves an abnormal opening in the interventricular septum, leading to a left-to-right shunt.
1. Clinical Presentation
| Finding | Description |
|---|---|
| Murmur | Harsh, holosystolic murmur heard best at the left lower sternal border. |
| Symptoms | Depends on size; small defects are often asymptomatic. Large defects cause failure to thrive, tachypnea, and diaphoresis with feeding. |
2. Pathophysiology and Complications
- Hemodynamics: Left-to-right shunt leads to increased pulmonary blood flow, which may eventually cause pulmonary hypertension.
- Eisenmenger Syndrome: A late-stage complication where high pulmonary resistance causes the shunt to reverse (right-to-left), leading to cyanosis.
- Infective Endocarditis: High-velocity jet flow increases the risk of vegetations on the tricuspid valve or defect edges.
NEET PG Hint: Remember the size-murmur paradox: Small VSDs produce loud, harsh murmurs due to high turbulence, while large, non-restrictive VSDs may have softer murmurs. If a child with a known VSD suddenly loses their murmur and develops cyanosis, suspect the development of Eisenmenger syndrome.