Question

A 10-year-old boy presents with exertional dyspnea and cyanosed lips. On examination, the precordium is silent, a systolic click is heard, but no cardiac murmur is present. Which is the most likely diagnosis?

• A. Tetralogy of Fallot
• B. Eisenmenger syndrome
• C. Idiopathic pulmonary hypertension
• D. Ebstein anomaly

Hint:

Disappearance of a previously loud VSD murmur + onset of cyanosis + loud $P_2$ pulmonary ejection click = Development of Eisenmenger Syndrome (shunt reversal due to severe irreversible PVR elevation).

Answer 1

The Correct Option is B

Concept:
Eisenmenger syndrome is the end-stage complication of an uncorrected large systemic-to-pulmonary (left-to-right) shunt, such as a large VSD, ASD, or PDA.
Severe, irreversible pulmonary arterial hypertension develops, leading to equalization of pressures and eventual shunt reversal (right-to-left) with central cyanosis.
Explanation:
• Chronic pulmonary overcirculation induces irreversible vascular remodeling with plexiform lesions, muscular hypertrophy of the media, and intimal proliferation in the pulmonary arterial bed.

• When pulmonary vascular resistance equals or exceeds systemic vascular resistance, the original left-to-right shunt diminishes and then reverses to a right-to-left shunt, causing central cyanosis, polycythemia, and digital clubbing.

• With equalization of ventricular or arterial pressures across the defect, high-velocity turbulent flow ceases; hence, the original systolic murmur disappears (the precordium becomes "silent").

• Auscultation classically reveals physical signs of severe pulmonary hypertension: a single or narrowly split, palpable and loudly accentuated pulmonic second sound ($P_2$), a pulmonary ejection systolic click due to sudden dilation of the main pulmonary artery, and possibly a high-pitched early diastolic Graham Steell murmur of functional pulmonary regurgitation.
Final Answer:
A child with cyanosis, disappearance of a previously present shunt murmur (silent precordium), and an audible pulmonary ejection click is exhibiting classic Eisenmenger syndrome.