Pulsus paradoxus is a clinical sign most commonly associated with which condition?

• A. Myocardial infarction.
• B. Pericardial tamponade.
• C. Pulmonary embolism.
• D. Aortic stenosis.

Answer: (B)

Pulsus paradoxus is an exaggerated drop in systolic blood pressure during inspiration—typically more than 10 mmHg. In cardiac tamponade, the accumulating pericardial fluid limits how the heart fills. When you breathe in, increased venous return to the right ventricle causes the septum to bulge toward the left ventricle, further restricting left ventricular filling and reducing stroke volume. That greater inspiratory fall in systolic pressure is the hallmark of pulsus paradoxus and is most characteristically seen with tamponade. While it can appear in some severe lung diseases or other pericardial conditions, the association with tamponade is the classic, most informative context for recognizing this sign.