Which physical sign is classically associated with cardiac tamponade?

Which physical sign is classically associated with cardiac tamponade?

• A. Pulsus paradoxus
• B. Kussmaul sign
• C. S4 gallop
• D. Rales

Answer: (A)

Tamponade makes filling of the heart during diastole highly sensitive to respiration because the fluid in the pericardial space keeps the heart compressed and intrathoracic pressure swings during breathing affect how much the ventricles can fill. During inspiration, increased venous return to the right side shifts the interventricular septum toward the left ventricle, reducing left ventricular preload and causing a noticeable drop in systolic blood pressure. This exaggerated inspiratory decline in systolic BP is pulsus paradoxus, a classic sign of tamponade (typically defined as a fall in systolic BP >10 mmHg with inspiration). Kussmaul sign is an inspiratory rise in jugular venous pressure seen in constrictive pericarditis or restrictive pathologies, not tamponade. An S4 gallop reflects a stiff or noncompliant ventricle and is not specific to tamponade. Rales indicate fluid in the lungs from pulmonary edema, which is also not a defining feature of tamponade. So the best answer is pulsus paradoxus because it directly reflects the respiratory-dependent fall in systolic pressure caused by the impaired filling and ventricular interdependence seen in cardiac tamponade.

Tamponade makes filling of the heart during diastole highly sensitive to respiration because the fluid in the pericardial space keeps the heart compressed and intrathoracic pressure swings during breathing affect how much the ventricles can fill. During inspiration, increased venous return to the right side shifts the interventricular septum toward the left ventricle, reducing left ventricular preload and causing a noticeable drop in systolic blood pressure. This exaggerated inspiratory decline in systolic BP is pulsus paradoxus, a classic sign of tamponade (typically defined as a fall in systolic BP >10 mmHg with inspiration).

Kussmaul sign is an inspiratory rise in jugular venous pressure seen in constrictive pericarditis or restrictive pathologies, not tamponade. An S4 gallop reflects a stiff or noncompliant ventricle and is not specific to tamponade. Rales indicate fluid in the lungs from pulmonary edema, which is also not a defining feature of tamponade.

So the best answer is pulsus paradoxus because it directly reflects the respiratory-dependent fall in systolic pressure caused by the impaired filling and ventricular interdependence seen in cardiac tamponade.