A 29-day old child presents with features of congestive cardiac failure and left ventricular hyperophy. Auscultation shows a sho systolic murmur. Most likely diagnosis is –
**Core Concept**
The question tests the understanding of a congenital heart defect that presents with congestive cardiac failure, left ventricular hypertrophy, and a characteristic systolic murmur in a neonate. This condition is a classic example of a left-to-right shunt lesion that can lead to increased pulmonary blood flow and subsequently pulmonary hypertension, resulting in congestive cardiac failure.
**Why the Correct Answer is Right**
The likely diagnosis is a Ventricular Septal Defect (VSD). A VSD is characterized by an abnormal opening in the interventricular septum, allowing blood to flow from the left ventricle to the right ventricle. This left-to-right shunt increases the volume load on the left ventricle, leading to left ventricular hypertrophy. The increased flow through the pulmonary valve can cause pulmonary hypertension, which in turn can lead to congestive cardiac failure. The characteristic systolic murmur heard in patients with VSD is due to the turbulent flow of blood through the defect.
**Why Each Wrong Option is Incorrect**
**Option A:** Tetralogy of Fallot is a cyanotic congenital heart defect characterized by right ventricular outflow tract obstruction, which would not typically present with congestive cardiac failure and left ventricular hypertrophy.
**Option B:** Atrial Septal Defect (ASD) is another type of left-to-right shunt lesion, but it is less likely to cause left ventricular hypertrophy and congestive cardiac failure in the neonatal period.
**Option C:** Patent Ductus Arteriosus (PDA) is a common congenital heart defect, but it typically presents with a continuous murmur (machinery murmur) due to the flow of blood from the aorta to the pulmonary artery.
**Clinical Pearl / High-Yield Fact**
In neonates, a VSD can cause significant left-to-right shunting, leading to congestive cardiac failure and eventually pulmonary hypertension. Early diagnosis and surgical repair are crucial to prevent long-term complications.
**Correct Answer: D. Ventricular Septal Defect (VSD)**