Question

A 26-year-old man complains of abdominal distension, swelling of the legs, and easy fatigability. His blood pressure is 90/70 mm Hg and the pulse becomes difficult to feel on inspiration. He has pedal oedema, ascites, and tender hepatomegaly. The precordium is quiet, with a loud and somewhat early apical third heart sound. The probable diagnosis is

• A. Cor pulmonale
• B. Tricuspid stenosis
• C. Constrictive pericarditis
• D. Pulmonary stenosis

Hint:

Think about what happens to ventricular filling when the pericardium itself becomes thick and rigid.

Answer 1

The Correct Option is C

Step 1: Understanding the Question:
A young man presents with right heart failure signs - ascites, pedal oedema, tender hepatomegaly, and a pulse that weakens on inspiration (pulsus paradoxus). The precordium is quiet but there is a loud, early apical third heart sound. We need to name the disease that produces exactly this combination.

Step 2: Key Concept or Approach:
When the pericardium becomes thickened and non-compliant, ventricular filling is normal in early diastole but is then abruptly halted once the stiff pericardial sac reaches its limit. This sudden stop in filling produces a loud, early extra sound called a pericardial knock, which can be mistaken for a third heart sound. Because the heart is encased in a rigid shell, cardiac impulses are also damped, giving a quiet precordium, and respiratory variation in intrathoracic pressure is not transmitted normally to the cardiac chambers, producing pulsus paradoxus. Restricted filling backs pressure into the systemic venous system, causing ascites, hepatomegaly, and oedema.

Step 3: Working Through the Options:
Cor pulmonale results from lung disease causing pulmonary hypertension; it typically shows a loud pulmonary second sound and signs of chronic lung disease, not a quiet precordium with an early knock. Tricuspid stenosis produces a diastolic murmur with an opening snap over the tricuspid area, not a pericardial knock, and is an uncommon isolated lesion at this age. Pulmonary stenosis gives an ejection systolic murmur at the pulmonary area and right ventricular hypertrophy, not this pattern of right heart failure with a knock. Constrictive pericarditis accounts for every finding together: the quiet precordium, the early loud sound (pericardial knock), the pulsus paradoxus, and the venous congestion picture of ascites, hepatomegaly, and oedema.

Step 4: Conclusion:
The probable diagnosis is constrictive pericarditis.